JP2020038345A - Imaging device, accessory device, and communication control method - Google Patents

Abstract

To perform communication between a camera body and an accessory at higher speed or at a most suitable speed.SOLUTION: A camera control unit 205 of an imaging device receives, from an accessory device, an accessory transmittable size that indicates a data size continuously transmittable by the accessory device and an accessory receivable size that indicates a data size continuously receivable by the accessory device. The camera control unit sets a first continuously receivable data size on the basis of the data size continuously receivable by the camera control unit and accessory transmittable size, and sets a first continuously transmittable data size on the basis of the data size continuously transmittable by the camera control unit and accessory receivable size, and performs communication with the accessory device in a data size with the first continuously receivable data size and the first continuously transmittable data size set to upper limits.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an imaging system including an imaging device (hereinafter, referred to as a camera body) capable of communicating with each other and an accessory device (hereinafter, simply referred to as an accessory) such as an interchangeable lens and an adapter.

  In the interchangeable lens type imaging system, adapters (intermediate accessories) such as a wide / teleconverter, a mount conversion adapter, and an ND filter adapter may be connected between the camera body and the interchangeable lens. In this case, it is necessary to transmit and receive a large amount of data at a high speed in order to realize high-quality imaging and smooth lens control. Further, in the combination of the camera body and the accessory, it is required to further increase and optimize the communication speed while guaranteeing mutual compatibility.

  Patent Literature 1 discloses an image pickup device that corrects optical information of an interchangeable lens based on optical information of the intermediate accessory when an intermediate accessory is connected between a camera body that communicates with the interchangeable lens and the interchangeable lens. A system is disclosed. In this imaging system, the correction process of the optical information is started because the intermediate accessory acquires the identification information of the interchangeable lens that is the communication slave as the communication master.

  Further, in the I2C communication system, which is a communication system for achieving one-to-many communication between a communication master and a plurality of communication slaves, one-to-many communication can be performed using two lines of a serial clock line and a serial data line.

Japanese Patent No. 5208169

  However, when the intermediate accessory becomes a communication master as in the imaging system disclosed in Patent Document 1, for example, when a plurality of intermediate accessories are connected between the camera body and the interchangeable lens, the processing is appropriately started or Can't run. Furthermore, in this imaging system, for example, "one-to-one" communication is performed while switching between the camera body and the accessory and between the accessories, and thus is not suitable for high-speed communication.

  On the other hand, the I2C communication system is a clock-synchronous open-drain communication, and the receiving side needs to return an acknowledgment (ACK) to the transmitting side for each data communication, so that high-speed communication is difficult.

  The present invention provides an imaging device and an accessory device capable of performing communication between the imaging device and the accessory device at a higher speed or an optimum communication speed.

  In the imaging device according to one aspect of the present invention, an accessory device is detachably mounted. The imaging device includes a camera communication unit that provides a communication path with the accessory device, and a camera control unit that communicates with the accessory device via the camera communication unit. The camera control unit receives, from the accessory device, an accessory transmittable size indicating a data size that can be continuously transmitted by the accessory device, and an accessory receivable size indicating a data size that can be continuously received by the accessory device. . Then, the camera control unit sets the first continuously receivable data size based on the continuously receivable data size and the accessory transmittable size, and the camera control unit sets the continuously receivable data size and the accessory receiveable size. The first continuous transmittable data size is set based on the size, and communication with the accessory device is performed using the first continuous receivable data size and a data size having the first continuous transmittable data size as an upper limit. And

  An accessory device according to another aspect of the present invention is detachably connected to an imaging device. The accessory device has an accessory communication unit that provides a communication path with the imaging device, and an accessory control unit that communicates with the imaging device and other accessory devices via the accessory communication unit. The accessory control unit transmits, to the imaging device, an accessory transmittable size indicating a data size that can be continuously transmitted by the accessory control unit and an accessory receivable size indicating a data size that can be continuously received by the accessory control unit. It is characterized by doing.

  Further, a communication control method according to another aspect of the present invention is applied to an imaging device to which an accessory device is detachably and communicatively attached. The communication control method receives, from an accessory device, an accessory transmittable size indicating a data size that the accessory device can continuously transmit, and an accessory receivable size indicating a data size that the accessory device can continuously receive. Setting the first continuous receivable data size based on the data size and the accessory transmittable size that can be continuously received by the imaging device; and the data size and accessory that the image capture device can continuously transmit. Setting the first continuously transmittable data size based on the receivable size, and communicating with the accessory device using the first continuously receivable data size and a data size up to the first continuously transmittable data size. Performing the steps.

  Note that an imaging system including the imaging device and the accessory device also constitutes another aspect of the present invention.

  Further, a communication control method according to another aspect of the present invention is applied to an accessory device detachably and communicatively attached to an imaging device. The communication control method includes: transmitting an accessory transmittable size indicating a data size that can be continuously transmitted by the accessory device to the imaging device; and transmitting an accessory receivable size indicating a data size that the accessory device can continuously receive. Transmitting to the imaging device.

  Note that a communication control program as a computer program for causing a computer of an imaging device or an accessory device to execute processing according to the communication control method also constitutes another aspect of the present invention.

  According to the present invention, communication between an imaging device and an accessory device can be performed at a higher speed or an optimum communication speed.

FIG. 2 is a block diagram illustrating the configuration of the camera system according to the first embodiment. FIG. 4 is a diagram illustrating a configuration for first communication according to the first embodiment. 5 is a flowchart illustrating a flow of a process of acquiring initial optical information and corrected optical information with the accessory according to the first embodiment. 5 is a flowchart illustrating initial communication processing between the camera and the lens according to the first embodiment. 5 is a flowchart illustrating an initial communication process between the camera and the accessory according to the first embodiment. 5 is a flowchart illustrating a flow of a process of determining a first accessory according to the first embodiment. 11 is a flowchart illustrating a flow of a process of searching for a dynamic accessory according to the second embodiment. 11 is a flowchart illustrating a flow of a correction process of optical information according to the operation of the dynamic accessory according to the second embodiment Diagram showing an example of information communicated in the initial communication 11 is a flowchart illustrating a flow of a process of acquiring correction identification information and a flow of a correction process using the correction identification information according to the third embodiment. FIG. 4 is a diagram illustrating a configuration for second communication according to the first embodiment. FIG. 7 is a diagram illustrating a modification of the first communication according to the first embodiment. FIG. 14 is a block diagram illustrating a configuration of a camera system according to a fourth exemplary embodiment in a case where an end is an interchangeable lens. FIG. 9 is a block diagram illustrating a configuration of a camera system when an end of the fourth embodiment is an intermediate accessory. 14 is a flowchart illustrating the flow of a process for detecting a communication error of the second communication according to the fourth embodiment. FIG. 13 is a block diagram illustrating a configuration of a camera system including a camera body, an interchangeable lens, and an intermediate adapter according to a fifth embodiment of the present invention. FIG. 14 is a diagram illustrating a configuration of a first communication circuit in a camera system according to a fifth embodiment. FIG. 17 is a waveform chart showing a format of communication data in the fifth embodiment. FIG. 19 is a waveform chart showing a communication waveform in a first communication mode in the fifth embodiment. FIG. 17 is another waveform chart showing a communication waveform in the first communication mode in the fifth embodiment. FIG. 17 is a waveform chart showing communication waveforms in a second communication mode in the fifth embodiment. FIG. 17 is a waveform chart showing communication waveforms at the time of communication mode switching in the fifth embodiment. 17 is a flowchart illustrating a processing procedure in a first communication mode according to the fifth embodiment. 17 is another flowchart illustrating the processing procedure in the first communication mode according to the fifth embodiment. 17 is a flowchart illustrating a processing procedure in a second communication mode according to the fifth embodiment. 17 is another flowchart illustrating the processing procedure in the second communication mode in the fifth embodiment. 15 is a flowchart illustrating a procedure for activating a camera body according to the fifth embodiment. FIG. 18 is a diagram illustrating a format of a memory map for each communication command according to the fifth embodiment. FIG. 18 is a diagram illustrating a format of a communication command according to the fifth embodiment. 16 is a flowchart illustrating a communication processing procedure using a memory map according to the fifth embodiment. 17 is a flowchart illustrating another communication processing procedure using a memory map according to the fifth embodiment. FIG. 17 is a diagram illustrating an extended format of a memory map for each communication command according to the sixth embodiment of the present invention.

Hereinafter, the accessory indicates an interchangeable lens or an intermediate accessory.

  In the following embodiments, each of the camera body, the interchangeable lens, and the intermediate accessory is also generally referred to as a unit. Further, each of the interchangeable lens and the intermediate accessory is also generally referred to as an accessory.

  In the following embodiments, the accessory related to correction is an interchangeable lens or an intermediate accessory whose correction processing necessity information is “necessary”.

  In the following embodiments, an intermediate accessory related to correction is an intermediate accessory that needs to correct optical information of an interchangeable lens.

  In the following embodiments, the first accessory is an accessory that holds optical information of all other accessories.

  Further, in the following embodiments, the first intermediate accessory is an intermediate accessory having optical information of another intermediate accessory.

  In the following embodiments, the first unit is a unit that holds optical information of all accessories.

  In addition. In the following embodiments, attention is paid to whether each unit has optical information of another unit, but this is not necessarily related to the release date or the manufacture date of the unit. For example, the optical information stored in each unit may change irrespective of the release date or manufacturing date of the unit due to firmware upgrade or the like.

  Hereinafter, Example 1 will be described.

<Configuration of camera system (Fig. 1)>
The configuration of the camera system according to the present embodiment will be described with reference to FIG.

  The camera system has a first communication path that is a communication path for transmitting control commands from the camera body 20 to the interchangeable lens 10 and for transmitting operation information and optical information from the interchangeable lens 10 to the camera body 20. Further, it has a second communication path which is a communication path for transmitting operation information and optical information between the camera body 20 and the plurality of intermediate accessories 30 and 40. Hereinafter, communication performed through the first communication path is also referred to as first communication (first communication), and communication performed through the second communication path is also referred to as second communication (second communication).

  Here, the first communication path is used to perform communication between the first communication unit 207 on the camera side and the first communication unit 114 on the lens side, and mounts 202 and 305, 303 and 405, 403, and 102 described later. This is a route performed through. The first communication unit 207 on the camera side and the first communication unit 114 on the lens side are examples of communication control means.

  As described above, communication performed by a certain unit with one unit different from the unit is also referred to as one-to-one communication in this embodiment.

  Here, the second communication path is a path in which the second communication unit 208 on the camera side communicates with the communication unit of each accessory. At this time, communication is performed from the second communication unit 208 on the camera side via the mounts 203 and 306, and communication is performed via at least a part of the mounts 304 and 406, 404 and 103. The communication unit 208 on the camera side communicates with, for example, the second communication unit 115 on the lens side and the second communication units 308 and 408 on the intermediate accessory side via the second communication path. The camera-side communication unit 208, the lens-side second communication unit 115, the intermediate accessory-side second communication unit 308, and the intermediate accessory-side 408 are each examples of communication control means.

  As described above, communication performed by a certain unit with a plurality of units different from the unit is also referred to as one-to-many communication in this embodiment.

  In FIG. 1, an interchangeable lens 10 is an interchangeable lens that controls a movable optical member for photographing. The camera body 20 is a camera body that captures an image. The intermediate accessory 30 and the intermediate accessory 40 are intermediate accessories such as extenders mounted between the interchangeable lens 10 and the camera body 20.

  The interchangeable lens 10, the intermediate accessory 40, the intermediate accessory 30, and the camera body 20 have detachable mounts 101 and 401, 402 and 301, and 302 and 201, respectively. Here, the mount 101 is provided on the interchangeable lens 10, the mounts 401 and 402 are provided on the intermediate accessory 40, the mounts 301 and 302 are provided on the intermediate accessory 30, and the mount 201 is provided on the camera body 20. .

  Each of the mounts 101, 401, 402, 301, 302, and 201 has a first communication contact group 102, 403, 405, 303, 305, which is a contact terminal group having one or more contacts for performing first communication. 202 is provided. Here, the first communication contact groups 102, 403, 405, 303, 305, and 202 are configured to conduct when the interchangeable lens 10, the intermediate accessory 30, the intermediate accessory 40, and the camera body 20 are connected. In the first embodiment, the first communication is also used for controlling the optical member of the interchangeable lens 10 by the camera body 20.

  Further, the mounts 101, 401, 402, 301, 302, and 201 respectively have second communication contact groups 103, 404, 406, 304, which are contact terminal groups having one or more contacts for performing the second communication. 306 and 203 are provided. Here, the second communication contact groups 103, 404, 406, 304, 306, and 203 are configured to conduct when the interchangeable lens 10, the intermediate accessory 30, the intermediate accessory 40, and the camera body 20 are connected. In the first embodiment, the second communication is configured such that the camera body 20 can perform one-to-many communication with the intermediate accessory 30, the intermediate accessory 40, and the interchangeable lens 10.

  As described above, the first communication that is one-to-one communication between the camera body 20 and the interchangeable lens 10 and the second communication that performs integral communication between the camera body and the plurality of accessories correspond to different first communication. A first communication path and a second communication path are provided. Thus, compared to the case where communication is performed using the same communication path, for example, in the first communication, it is possible to transmit an interchangeable lens control command to the interchangeable lens at a more intended timing. Since the transmission of the interchangeable lens control command can be transmitted to the interchangeable lens immediately at the timing intended by the camera body, a plurality of optical members mounted on the interchangeable lens can be controlled at high speed and with high accuracy.

  The interchangeable lens 10 includes a focus lens 104, a zoom lens 105, an iris 106, a blur correction lens 107, a control unit (108 to 111) for controlling each optical member, and a lens control unit for controlling the entire lens. 113 is provided. Further, the interchangeable lens 10 includes a first communication unit 114 on the lens side that performs the first communication, a second communication unit 115 on the lens side that performs the second communication, a blur amount detection unit 112 that detects a blur amount, and an interchangeable lens. A lens operation member 116 is provided as an operation member. Each configuration will be described.

  The focus lens 104 is for changing the focus state of a captured image. The zoom lens 105 is for zooming a captured image. The iris 106 is for adjusting the amount of light of a captured image. The blur correction lens 107 is a blur correction lens for correcting image blur of a subject image.

  The focus lens control unit 108 performs position detection and drive control of the focus lens 104. The zoom lens control unit 109 performs position detection and drive control of the zoom lens 105. The iris control unit 110 performs position detection and drive control of the iris 106. The shake correction control unit 111 is a shake correction control unit that performs position detection and drive control of the shake correction lens 107. Each of the focus lens control unit 108, the zoom lens control unit 109, the iris control unit 110, and the shake correction control unit 111 includes, for example, a position sensor such as an absolute encoder and a drive motor such as an ultrasonic motor or a stepping motor. The blur amount detection unit 112 detects the amount of vibration of the interchangeable lens 10, and is configured by, for example, a gyro sensor.

  The lens control unit 113 controls the lens and has a memory (not shown). The lens control unit 113 is an example of a communication control unit. The lens side first communication unit 114 is for performing first communication with the interchangeable lens 10. The lens-side second communication unit 115 is for performing the second communication with the interchangeable lens 10.

  The memory provided in the lens control unit 113 is constituted by a rewritable nonvolatile memory, and stores control software (firmware) executed by the CPU, and unique information and status information on the interchangeable lens 10. The unique information is, for example, a model name (identification information), optical characteristics, correction information, and the like. The state information includes, for example, an operation state (normal / safe mode), position information (or magnification) of the zoom lens 105, position information of the focus lens 104, F value of the iris 106, position information of the blur correction lens 107, firmware version, Update status. However, it is not limited to these. The memory also stores a program to be executed when operating the interchangeable lens 10 in a safe mode described later.

  The lens control unit 113 has a programmable processor such as a CPU, and realizes various operations including an operation of the interchangeable lens 10 described later by reading a program from a memory and executing the program. For example, the lens control unit 113 performs an operation according to a command received from the camera control unit 205 in first communication described below. The operation according to the command includes, for example, controlling the focus lens control unit 108, the zoom lens control unit 109, the iris control unit 110, and the blur correction control unit 111, and updating the firmware stored in the memory.

  The lens control unit 113 updates the firmware by overwriting the old firmware stored in the memory with, for example, the new firmware received from the camera body 20 in the first communication. The lens control unit 113 manages the update process by recording data (update status data) indicating the status of the firmware update process in the memory. For example, the lens control unit 113 sets the update state data to a value indicating “incomplete” before overwriting the firmware, and sets the update state data to a value indicating “completed” when the firmware overwrite is completed. Note that the value indicating “completed” may be different between the value indicating “normal completion” and the value indicating “abnormal completion”. The value indicating “abnormal completion” may be a different value depending on the cause of the abnormality.

  For example, if the interchangeable lens 10 is detached during the firmware update, the power supply to the interchangeable lens 10 is cut off, and the update process is interrupted with the update state data indicating a value indicating “incomplete”. For example, the lens control unit 113 checks the update state data when the power is supplied again, and if the value indicates the incomplete state, the operation of the lens control unit 113 is limited because the firmware update is suspended. To the specified mode (safe mode). Further, the operation state of the interchangeable lens 10 stored in the memory is rewritten to the safe mode. In the safe mode, only limited functions including the processing required for updating the firmware can be executed. The processing required for updating the firmware is, specifically, processing for transmitting the identification information and the operation state information (or a request for updating the firmware) of the interchangeable lens 10 to the camera body 20. The process of updating the firmware recorded in the memory with the firmware received from the camera body 20 is also a process necessary for updating the firmware.

  Other processes, such as control of the focus lens control unit 108, cannot be performed.

  Usually, the capacity of the memory is not large enough to store the entire firmware in duplicate. Therefore, the capacity available for storing the program for the safe mode is limited. Therefore, in the safe mode, only limited functions including the minimum necessary functions such as transmission of the operation state of the interchangeable lens 10 and update of firmware are provided. When the lens controller 113 receives a request for processing that cannot be executed in the safe mode, for example, a request for driving the focus lens 104, in the first communication during the safe mode, the request is ignored. The lens operation member 116 is an operation member provided on the interchangeable lens 10, and is, for example, a switch or an electronic ring. When the lens operation member 116 is operated, an operation signal is output to the lens control unit 113.

  Next, the configuration of the camera body 20 will be described. The camera body 20 includes an image sensor 204, a camera control unit 205 that controls the camera body, an image display unit 206 that displays images captured by the camera body 20, and a camera operation member 209 that is an operation member provided on the camera body 20. Is provided. Further, the camera body 20 includes a camera-side first communication unit 207 and a camera-side second communication unit 208 that control the first communication and the second communication. Each configuration will be described.

  The image sensor 204 is an image sensor for capturing an image, and is, for example, a CMOS image sensor.

  The camera control unit 205 is for controlling the camera body and has a memory (not shown). The camera control unit 205 is an example of a communication control unit. The camera-side first communication unit 207 is for performing first communication in the camera body 20. The camera-side second communication unit 208 is for performing the second communication in the camera body 20. The camera control unit 205, the camera-side first communication unit 207, and the camera-side second communication unit 208 are configured using a CPU in the camera body 20, for example.

  The image display unit 206 is, for example, a liquid crystal monitor, and is used for displaying an image captured by the camera body 20, image data recorded on the recording medium 211, a GUI, and the like. At this time, the video display unit 206 is also used to display a menu for a user to instruct firmware update of the interchangeable lens 10 or the intermediate accessories 30 and 40. When the camera control unit 205 detects that the attached interchangeable lens 10 and the intermediate accessories 30 and 40 are in the safe mode, the camera control unit 205 can notify the user of the necessity of updating the firmware by displaying a message or the like. .

  The camera operation member 209 is for setting photographing conditions, and is, for example, a dial ring or a switch. When the camera operation member 209 is operated, an operation signal is output to the camera control unit 205.

  The media IF 210 is an interface for recording and reading data on a recording medium 211 which is, for example, a removable memory card.

  The recording medium 211 is used as a recording destination of image data and audio data obtained by photographing with the camera body 20. The recording medium 211 is also used as a new firmware supply source when updating the firmware of the camera body 20, the interchangeable lens 10, and the intermediate accessories 30, 40.

  Each of the intermediate accessories 30, 40 includes intermediate accessory optical members 307, 407, an intermediate accessory-side second communication unit 308, 408 for performing the second communication, and 309, 409 for controlling the intermediate accessory. Further, each of the intermediate accessories 30, 40 includes intermediate accessory operation members 310, 410, which are operation members provided on the intermediate accessory. Each configuration will be described.

  The intermediate accessory optical members 307 and 407 of the present embodiment are, for example, optical members that change the optical characteristics of a captured image, such as a variable power lens and an ND filter.

  The intermediate accessory side second communication units 308 and 408 are communication units for performing the second communication with the intermediate accessory 30 and the intermediate accessory 40.

  The intermediate accessory control units 309 and 409 are control units for controlling the intermediate accessory 30 and the intermediate accessory 40, respectively, and have a memory (not shown). Each of the intermediate accessory control units 309 and 409 is an example of a communication control unit. The intermediate accessory control units 309 and 409 and the intermediate accessory side second communication units 308 and 408 are configured using a CPU of the intermediate accessory.

  The memory of the intermediate accessory control units 309 and 409 is configured by a rewritable nonvolatile memory, and stores control software (firmware) executed by the CPU, and unique information and status information on the intermediate accessories 30 and 40. The unique information is, for example, a model name (identification information), optical characteristics, correction information, and the like. The state information includes, for example, an operation state (normal / safe mode), operation information (position and speed) of the intermediate accessory operation members 310 and 410, a firmware version and an update state, and the like. However, it is not limited to these. The memory also stores a program to be executed when operating the intermediate accessories 30 and 40 in a safe mode described later.

  Further, the intermediate accessory control units 309 and 409 have a programmable processor such as a CPU, and realize various operations including an operation of the intermediate accessories 30 and 40 described later by reading a program from a memory and executing the program. I do. For example, the intermediate accessory control units 309 and 409 operate in accordance with a command received from the camera control unit 205 in the second communication described below, for example, transmission of operation information of the intermediate accessory operation members 310 and 410, and firmware of the firmware stored in the memory. Perform an update.

  The intermediate accessory control units 309 and 409 update the firmware by overwriting the old firmware stored in the memory with, for example, the new firmware received from the camera body 20 in the first communication. Further, the intermediate accessory control units 309 and 409 manage the update process by recording data (update status data) indicating the status of the firmware update process in the memory. For example, the intermediate accessory control units 309 and 409 set the update state data to a value indicating “incomplete” before overwriting the firmware, and set the update state data to a value indicating “completed” when the firmware overwrite is completed. Note that the value indicating “completed” may be different between the value indicating “normal completion” and the value indicating “abnormal completion”. The value indicating “abnormal completion” may be a different value depending on the cause of the abnormality.

  For example, if the intermediate accessories 30 and 40 are removed during the firmware update, the power supply to the intermediate accessories 30 and 40 is cut off, so that the update process is interrupted with the update status data indicating a value indicating “incomplete”. You. For example, the intermediate accessory control units 309 and 409 check the update state data when the power is supplied again, and when the value indicates the incomplete state, shift to the mode in which the operation is restricted (safe mode). . Further, the operation state of the intermediate accessories 30 and 40 stored in the memory is rewritten to the safe mode.

  In the safe mode, only limited functions including the processing required for updating the firmware can be executed. The processing required for updating the firmware is, specifically, the authentication information such as the identification information of the intermediate accessories 30 and 40 and the information indicating the safe mode (or a request for the firmware update) to the camera body 20. This is the transmission process. Further, the process of updating the firmware recorded in the memory with the firmware received from the camera body 20 is also a process necessary for updating the firmware. Other processes, such as transmission of operation information of the intermediate accessory operation members 310 and 410, cannot be performed.

  Usually, the capacity of the memory is not large enough to store the entire firmware in duplicate. Therefore, the capacity available for storing the program for the safe mode is limited. Therefore, in the safe mode, only limited functions are provided, including minimum necessary functions such as transmission of the operation status of the intermediate accessories 30 and 40 and update of firmware. The intermediate accessory control units 309 and 409 ignore the request in the second communication during the safe mode when a request for a process that cannot be executed in the safe mode, for example, when transmission and reception of operation information of the intermediate accessory operation members 310 and 410 is received.

  The intermediate accessory operation members 310 and 410 are operation members provided on the intermediate accessory 30 and the intermediate accessory 40, respectively, and are, for example, switches or electronic rings. When the intermediate accessory operation members 310 and 410 are operated, an operation signal is output to the intermediate accessory control units 309 and 409.

  The second communication connection switch 311 and the second communication connection switch 411 are switches provided on the second communication line of the intermediate accessory 30 and the intermediate accessory 40, respectively, and on the lens side of the intermediate accessory side second communication unit. The second communication connection switch 311 and the second communication connection switch 411 can control short-circuiting / opening by the intermediate accessory control unit 309 and the intermediate accessory control unit 409, respectively. By providing these, the second communication on the lens side from itself can be cut off. That is, by controlling the short-circuit / release of these switches, the communication state of the second communication can be changed.

  In the first embodiment, the flow until the light incident on the interchangeable lens 10 is output as an image is as follows.

  The light that has entered the interchangeable lens 10 passes through the focus lens 104, the zoom lens 105, the iris 106, the shake correction lens 107, the intermediate accessory optical members 407 and 307, forms an image on the image sensor 204, and is converted into an electric signal. The electric signal output from the imaging element 204 is converted into a video signal by the camera control unit 205 and output to the video display unit 206.

<First communication (FIG. 2)>
Next, the first communication will be described with reference to FIG.

  FIG. 2A shows a configuration for performing the first communication. The first communication according to the present embodiment exemplifies a case in which clock synchronous communication is performed, but asynchronous communication may be performed. Asynchronous communication will be described later as a modification. The first communication contact groups 102, 403, 405, 303, 305, and 202 respectively have first communication LCLK terminals 102a, 403a, 405a, and 303a that are terminals of the clock line LCLK output from the camera-side first communication unit 207. , 305a, and 202a. The present embodiment also includes first communication DCL terminals 102b, 403b, 405b, 303b, 305b, and 202b, which are terminals of a data line DCL similarly output from the camera-side first communication unit 207 for clock synchronous communication. I have. Each of the first communication DCL terminals 102b, 403b, 405b, 303b, 305b, and 202b is an example of a first communication terminal. Similarly, first communication DLC terminals 102c, 403c, 405c, 303c, 305c, and 202c, which are terminals of a data line DLC output from the lens-side first communication unit 114 for clock synchronous communication, are included. Each of the first communication DLC terminals 102c, 403c, 405c, 303c, 305c, and 202c is an example of a third communication terminal.

  As shown in FIG. 2A, the clock line LCLK and the data line DCL are pulled up in the interchangeable lens 10. The clock line LCLK and the data line DLC are pulled up in the camera body 20.

  The clock line LCLK, the data line DCL, and the data line DLC in the intermediate accessory 30 and the intermediate accessory 40 are short-circuited between the first communication contacts 403 and 405 and between the first communication contacts 303 and 305, respectively.

  FIG. 2B shows waveforms of the clock line LCLK, the data line DCL, and the data line DLC during the first communication. The camera-side first communication unit 207 outputs a clock to the clock line LCLK and outputs 8-bit data of B7 to B0 to the data line DCL in accordance with a rising signal of the clock line LCLK. Similarly, the lens-side first communication unit 114 outputs 8-bit data of B7 to B0 to the data line DLC in accordance with the rising signal of the clock line LCLK. Further, the camera-side first communication unit 207 receives 8-bit data of B7 to B0 of the data line DLC in accordance with the rising signal of the clock line LCLK. Similarly, the lens-side first communication unit 114 receives 8-bit data of B7 to B0 of the data line DCL in accordance with the rising signal of the clock line LCLK. As described above, the camera-side first communication unit 207 and the lens-side first communication unit 114 can exchange communication data with each other. Upon receiving the 8-bit data of B7 to B0 of the data line DCL, the lens-side first communication unit 114 outputs the clock line LCLK LOW for a period of Tbusy, and thereafter releases the LOW output. Here, the Tbusy time is a time during which the interchangeable lens 10 processes received data, and the camera-side first communication unit 207 does not perform data transmission until the clock line LCLK changes from LOW to HIGH after data transmission. ing. By this signal control, the flow control of the first communication can be performed. By repeating the above processing, data can be transmitted between the camera-side first communication unit 207 and the lens-side first communication unit 114 by the first communication.

<Second communication (FIG. 11)>
Next, referring to the configuration diagram of FIG. 11, one of communication circuits capable of performing “one-to-many” communication formed between the camera body 20, the interchangeable lens 10, the intermediate accessory 30, and the intermediate accessory 40 Will be described. Note that the communication circuit is not limited to this as long as one-to-many communication is possible. Further, when a plurality of communication circuits are provided, the other communication circuits may be one-to-one communication such as clock-synchronized serial communication or UART communication.

  The camera-side second communication unit 208, the lens-side second communication unit 115, and the intermediate accessory second communication units 308 and 408 are connected via the contact unit similarly to the first communication. More specifically, they are connected via the above-mentioned second communication contact group 103, 404, 406, 304, 306, 203. In the present embodiment, the second communication contact groups 103, 404, 406, 304, 306, 203 are respectively CS signal terminals 103a, 404a, 406a, 304a, 306a, 203a and DATA signal terminals 103b, 404b, 406b, 304b, 306b. , 203b. The camera-side second communication unit 208, the lens-side second communication unit 115, and the intermediate accessory second communication unit 308 are a CS signal line connected via a CS signal terminal and a DATA signal line connected via a DATA signal terminal. Communication is performed using.

  Note that the DATA signal terminals of the second communication contact groups 103, 404, 406, 304, 306, and 203 are examples of the second communication terminals.

  The camera communication circuit includes a ground switch 221 and an input / output switch 222. The lens communication circuit includes a ground switch 121 and an input / output switch 122. The intermediate accessory communication circuit includes ground switches 321 and 421 and input / output changeover switches 322 and 422.

  The signal lines include a CS signal line (first signal line) for transmitting a signal for performing communication flow control and a DATA signal line (second signal line) for transmitting data to be transmitted and received. It is composed of books.

  The CS signal line is connected to the camera-side second communication unit 208, the intermediate accessory second communication unit 308, and the lens-side second communication unit 115, and has a configuration capable of detecting the state (Hi / Low) of the signal line. . The CS signal line is connected to a power source (not shown) in the camera body by pull-up. The CS signal line is configured to be connectable to GND via the ground switch 121 of the interchangeable lens 10, the ground switch 221 of the camera body 20, and the ground switches 321 and 421 of the intermediate adapter (open drain connection). With this configuration, the state of the CS signal line of the interchangeable lens 10, the camera body 20, and the intermediate accessories 30 and 40 can be set to Low by turning on (connecting) the ground switches. On the other hand, when the interchangeable lens 10, the camera body 20, and the intermediate accessories 30, 40 all turn off (cut off) their connection switches, the state of the CS signal line can be set to Hi. The CS signal line is used to distinguish between broadcast communication and P2P communication, or to switch communication directions in P2P communication.

  The DATA signal line is a single bidirectional data transmission line that can be used while switching the data propagation direction. The DATA signal line can be connected to the lens side second communication unit 115 via the input / output switch 122 of the interchangeable lens 10. Further, the DATA signal line can be connected to the camera-side second communication unit 208 via the input / output switch 222 of the camera body 20. Further, the DATA signal line can be connected to the intermediate accessory second communication units 308 and 408 via the input / output changeover switches 322 and 422 of the intermediate accessories 30 and 40, respectively. Each microcomputer is provided with a data output unit (CMOS system) for transmitting data and a data input unit (CMOS system) for receiving data. By operating the input / output switch, it is possible to select whether to connect the DATA signal line to the data output unit or to the data input unit. With this configuration, when transmitting the data, the interchangeable lens 10, the camera body 20, and the intermediate accessories 30, 40 operate the input / output changeover switches so that the DATA signal line is connected to the data output unit. Transmission becomes possible. On the other hand, when receiving the data, the interchangeable lens 10, the camera body 20, and the intermediate accessories 30, 40 operate the respective input / output changeover switches so as to connect the DATA signal line to the data input unit. It becomes possible.

  Here, broadcast communication and P2P communication performed by the CS signal and the data signal will be described.

  The CS signal line falls to LOW when any unit connects to GND, and is used as a trigger for broadcast communication.

  Broadcast communication is started when the camera body, which is the main body of communication, pulls the CS signal line LOW. The data received by the accessory via the DATA line when the CS signal line is LOW is determined to be broadcast data.

  Also, each accessory can request broadcast communication from the camera body by pulling the CS signal line LOW.

  The unit that has detected the LOW of the CS signal line can turn on its own grounding switch during the broadcast processing to notify other units that the processing for the broadcast communication is continuing. By defining that the second communication starts with the broadcast communication and ends with the broadcast communication, the DATA signal line of the accessory may basically maintain the receiving state. When the camera performs P2P communication with an accessory, first, an accessory to be communicated is designated by broadcast communication. The camera that has completed the transmission of the broadcast communication and the designated accessory perform the P2P communication.

  In P2P communication, first, a camera transmits data, and an accessory receiving the data transmits the data to the camera. Thereafter, this is performed alternately. In P2P communication, a CS signal during communication is kept at HIGH to be distinguished from broadcast communication. The CS signal in P2P communication is used as a busy signal. That is, the camera and the accessory make LOW to notify the other party that the data transmission from themselves has ended, and make HIGH to notify that the preparation for data reception is completed.

  When the P2P communication ends, the camera broadcasts the end of the P2P communication.

  In this way, the camera can perform data communication with a plurality of accessories via two communication lines.

  Note that although FIG. 1112 illustrates an example of a communication circuit in the present invention, the present invention is not limited to this. For example, the CS signal line is connected to GND in the camera body 20 by pull-down connection, and is connected to the ground switch 121 of the interchangeable lens 10, the ground switch 221 of the camera body 20, and the ground switches 321 and 421 of the intermediate accessories 30 and 40 (not shown). It may be configured to be connectable to a power supply. Further, the DATA signal line may be always connected to each data input unit, and the connection / disconnection between the DATA signal line and each data output unit may be operated by a switch.

  The second communication can be realized by the same communication method as the first communication, bidirectional asynchronous communication, master / slave method, token passing method, or the like.

<Initial communication with accessory and acquisition of corrected optical information (FIG. 3)>
Next, a flow in which the camera body 20 acquires the authentication information of the accessory by initial communication with the accessory, and further acquires the optical information of the interchangeable lens 10 corrected based on the optical information of the intermediate accessory 30 and the intermediate accessory 40 is shown. 3 will be described. The optical information of the intermediate accessory is, for example, a magnification that changes when the intermediate accessory is inserted when the intermediate accessory has a variable power lens. The optical information of the interchangeable lens 10 is, for example, information such as a focal length, an aperture, a focus sensitivity, and a focus correction amount.

  FIG. 3 shows a process in which the camera body 20 acquires the optical information of the interchangeable lens 10 corrected based on the optical information of the intermediate accessory 30 and the intermediate accessory 40 after the power is supplied for the first time after the intermediate accessory and the interchangeable lens are mounted. It shows the flow.

  When the camera body 20 is activated in S301, the process proceeds to S302.

  In step S302, the camera body 20 supplies power to the interchangeable lens 10, the intermediate accessory 30, and the intermediate accessory 40 via a power supply mounting contact (not shown), and the process proceeds to steps S303 and S304.

  In step S303, the camera control unit 205 performs initial communication with the interchangeable lens 10 in the first communication. In the initial communication, the authentication information of the interchangeable lens 10 is obtained.

  Here, the authentication information of the interchangeable lens 10 includes the identification information of the interchangeable lens 10 and the operation state information. The interchangeable lens identification information may be information such as a model number (ID) used to identify the type (model) of the interchangeable lens, or may be optical data identification information indicating optical data unique to the interchangeable lens. . Further, the information may include information indicating a function of the interchangeable lens or information such as a manufacturing number (serial number) capable of identifying an individual in the same model.

  The operating state information is information that can identify whether the interchangeable lens 10 is operating normally or is operating in the safe mode. In other words, the operating state information is a state in which the update of the firmware is interrupted (operating in the safe mode) or not. (Normal operation) is information that can be identified.

  The flow of the sub-process S303 for acquiring the authentication information of the interchangeable lens 10 in the first communication will be described later with reference to FIG.

  In step S304, the camera control unit 205 performs initial communication with the accessory through the second communication, and acquires authentication information of the accessory.

  Here, the accessory authentication information includes accessory identification information, correction processing necessity information, and operation state information.

  The intermediate accessory identification information may be information such as a model number (ID) used for identifying the type (model) of the intermediate accessory, or may be optical data identification information indicating optical data unique to the intermediate accessory. . Further, the information may include information indicating a function of the intermediate accessory or information such as a manufacturing number (serial number) capable of identifying an individual in the same model.

  The correction processing necessity information is information indicating whether the optical information of the interchangeable lens 10 needs to be corrected by mounting the accessory. If the accessory is an intermediate accessory and does not affect the optical system of the interchangeable lens 10, the correction process is not required. If the camera control unit 205 knows in advance from the intermediate accessory correction processing necessity information that the correction process by mounting the intermediate accessory is unnecessary, the camera ignores the intermediate accessory in the process of acquiring the optical information of the interchangeable lens 10. can do.

  As an intermediate accessory that does not require correction processing, for example, there is an intermediate accessory that has an optical member optically designed to cancel the influence of its own width on the optical system and is attached for the purpose of increasing the number of operation members. Also, there is a mount converter that changes the flange back length suitable for the camera body by being mounted between the camera body and the interchangeable lens having a short flange back mount.

  The operating state information is information that can identify whether the intermediate accessories 30 and 40 are operating normally or operating in the safe mode. In other words, the operating state information is a state in which the firmware update is interrupted (operating in the safe mode), It is information that can be identified whether or not (normal operation).

  The flow of the sub-process S304 of acquiring the authentication information of the intermediate accessory by the second communication will be described later with reference to FIG. Since steps S303 and S304 use different communication paths, the processing may be performed in parallel or sequentially.

  When the authentication information of the interchangeable lens and the authentication information of the attached accessory are acquired in S303 and S304, the process proceeds to S305.

  In step S305, the camera control unit 205 determines whether there is an intermediate accessory that needs to correct the optical information of the interchangeable lens based on the correction processing necessity information acquired in step S304. If an intermediate accessory whose correction processing necessity information is “necessary” (also referred to as an intermediate accessory related to correction) is attached, the process proceeds to S306.

  In step S306, the camera control unit 205 determines whether there is an accessory for which the camera control unit 205 does not have optical information among the interchangeable lenses and the intermediate accessories for which the correction processing necessity information is “necessary” in step S305. Judge. Note that the interchangeable lens and the intermediate accessory for which the correction processing necessity information is “necessary” in S305 are also referred to as accessories related to correction. If the camera control unit 205 does not have optical information among the accessories related to the correction, the camera control unit 205 cannot correct the optical information of the interchangeable lens. In this case, the process proceeds to S307 to search for a request destination of the correction process.

  In step S307, the camera control unit 205 determines an accessory (also referred to as a first accessory) that holds optical information of all other accessories among the accessories related to the correction. As a method of determining the first accessory, for example, a determination may be made based on identification information acquired from the accessory, or an inquiry may be made to the accessory by communication. Details will be described later with reference to FIG.

  When the first accessory is determined in S307, the process proceeds to S308.

  In step S308, the camera control unit 205 transmits the identification information of the accessory related to other correction to the first accessory determined in step S307, and requests the first accessory to correct optical information of the interchangeable lens 10. In this embodiment, as an example, when the first accessory is an interchangeable lens, communication is performed by the first communication. When the first accessory is an intermediate accessory, communication is performed by the second communication.

  The control unit of the first accessory that has received the correction request in S308 performs a correction process of the optical information of the interchangeable lens 10 using the stored optical information of the accessory related to other correction.

  In step S309, the camera control unit 205 acquires the optical information corrected by the first accessory.

  On the other hand, in step S306, the camera control unit 205 determines that the camera control unit 205 does not include any of the interchangeable lenses and the intermediate accessories for which the correction processing necessity information is “necessary” in step S305. In this case, the process proceeds to S310. In this case, the camera control unit 205 holds optical information of all accessories.

  In step S310, the camera control unit 205 corrects the optical information of the interchangeable lens using the optical information of the interchangeable lens and the optical information of the intermediate accessory held by the camera control unit 205.

  In S305, if the camera control unit 205 determines that there is no intermediate accessory that requires correction of the optical information of the interchangeable lens, the correction processing of all the intermediate accessories that are not attached or that are attached. The necessity information is “no”. Therefore, the process proceeds to S311 as a process when it is not necessary to correct the optical information of the interchangeable lens.

  In step S311, it is determined whether or not the camera body 20 holds the optical information of the interchangeable lens 10 based on the identification information of the interchangeable lens 10 included in the interchangeable lens authentication information acquired in step S303. When the camera control unit 205 does not hold the optical information of the interchangeable lens, the process proceeds to S312.

  In step S312, the camera control unit 205 acquires the optical information of the interchangeable lens 10 from the lens control unit 113 through the first communication.

  On the other hand, if it is determined in S311 that the optical information of the interchangeable lens 10 is held, the camera control unit 205 acquires the optical information from the data table in the camera in S313.

  After acquiring the optical information in S309, S310, S312, or S313, the process transits to S314, and the optical information acquisition sequence ends.

  After obtaining the optical information, the first communication path is used for communication for the camera body 20 to control the interchangeable lens 10, and the second communication path is used for the camera body 20 to operate the intermediate accessory operating member 310 and the intermediate accessory operating member 410. Is used for communication for constantly acquiring the operation information of. The communication for constantly acquiring the operation information of the operation member 116 of the interchangeable lens is performed in consideration of the occupancy of each communication path and the immediacy required for communication and control, by taking into consideration the first communication path and the second communication path. May be used.

<Initial communication processing by first communication between camera and interchangeable lens (FIG. 4)>
FIG. 4 shows a flow of a sub-process S303 which is initial communication performed by the camera body 20 with the interchangeable lens 10 in the camera system of the first embodiment. In the initial communication, the camera control unit 205 acquires the authentication information of the interchangeable lens 10 from the lens control unit 113.

  When the sub process is started in S401, the process proceeds to S402.

  In step S402, the camera control unit 205 transmits an interchangeable lens authentication information transmission request (corresponding to the first transmission request) to the lens control unit 113 by the first communication.

  Here, the interchangeable lens authentication information request according to the present embodiment will be described with reference to FIG. 910A. The interchangeable lens authentication information request according to the present embodiment is information that requests the interchangeable lens 10 to transmit two pieces of information, which are authentication information, to the camera control unit 205. The authentication information request includes a request for identification information of the interchangeable lens and a request for operation state information.

  In step S403, when the lens control unit 113 receives the interchangeable lens authentication information transmission request, the process proceeds to step S404. Then, the lens control unit 113 transmits the interchangeable lens authentication information (corresponding to the first information) to the camera control unit 205 by the first communication.

  Here, the authentication information transmitted from the interchangeable lens 10 to the camera control unit 205 will be described with reference to FIG. 910B. The authentication information includes identification information and operation state information.

  When the camera control unit 205 receives the interchangeable lens authentication information in S405, the process proceeds to S406 and stores the received interchangeable lens authentication information.

  With S407, the sub-process S303 ends.

<Initial communication processing by the second communication between the camera and the intermediate accessory (FIG. 5)>
FIG. 5 is a diagram illustrating the flow of a sub-process S304, which is an initial communication process performed by the camera body 20 and the accessory in the camera system according to the first embodiment. In the initial communication, the camera control unit 205 acquires the authentication information of the accessory. The accessory authentication information will be described later.

  When the sub process is started in S501, the process proceeds to S502.

  In step S502, the camera control unit 205 transmits an accessory authentication information request (corresponding to the second transmission request) to the intermediate accessory control unit 309 by the second communication.

  Here, the authentication information request of the accessory according to the present embodiment will be described with reference to FIG. 910C. The accessory authentication information request is information requesting that the accessory transmit accessory authentication information to the camera control unit 205. In this embodiment, the accessory authentication information includes accessory identification information, operating state information, correction processing necessity information, and termination information.

  When the intermediate accessory control unit 309 receives the accessory authentication information request in S503, the process proceeds to S506.

  In S506, the intermediate accessory control unit 309 transmits the authentication information of the intermediate accessory 30 to the camera control unit 205 by the second communication.

  Here, the authentication information transmitted from the intermediate accessory to the camera control unit 205 will be described with reference to FIG. 910D. The authentication information includes identification information (an example of third information), operating state information, correction processing necessity information, and termination information.

  The correction processing necessity information is information indicating “necessary” if the intermediate accessory changes optical characteristics. If the optical characteristics are not changed, the information indicates "No".

  In the present embodiment, the terminating information is information indicating whether or not the second communication is a terminating point as viewed from the camera body 20. If the intermediate adapter is at the end of the second communication as viewed from the camera main body 20, the end information is information indicating "end". If it is not the end of the second communication as viewed from the camera body 20, the end information is information indicating "not the end".

  In the one-to-many communication such as the second communication, a transmission destination can be designated by, for example, adding identification information of an accessory to the head of communication data. However, at the stage of S502, since the camera control unit 205 does not have any accessory information, it is not possible to specify the transmission destination by the communication data.

  Therefore, as an example of means for the camera body 20 to sequentially communicate with a plurality of accessories in this sub-process, there is a method using the second communication connection switch 311 and the second communication connection switch 411 as follows. It is assumed that the second communication connection switch 311 and the second communication connection switch 411 are short-circuited in the steady state.

  In step S501, the camera control unit 205 transmits the sub-process start information through the second communication. Since the second communication connection switch 311 and the second communication connection switch 411 are short-circuited, each accessory receives the sub-process start information. Each intermediate accessory that has received this sub-process start information opens its own second communication connection switch. Thus, only the intermediate accessory control unit 309 is connected to the camera control unit 205, and can receive data transmitted by the camera control unit 205. When the intermediate accessory control unit 309 that has completed the processing for the received data short-circuits the second communication connection switch 311, the intermediate accessory control unit 409 can receive the data transmitted by the camera control unit 205. The intermediate accessory 30 that has short-circuited the second communication connection switch does not respond to the transmission information of the camera control unit 205 until receiving the sub-process end information transmitted by the camera control unit 205 in S522 where the sub-process ends.

  In the present embodiment, even when the intermediate accessory 30 operates in the safe mode, the camera body 20 and the intermediate accessory 30 do not end the sub-process, and the accessory connected via the intermediate accessory 30 does not end. Initial communication with. However, when an accessory operating in the safe mode is mounted, initial communication with the mounted accessory via the accessory may not be performed. For example, when the operation state of the intermediate accessory 30 is the safe mode, the intermediate accessory control unit 309 does not short-circuit the second communication connection switch 311 even when the processing on the received data ends. Then, the sub-process may be immediately terminated by transmitting the authentication information to the camera control unit 205 by setting the terminal information to “end”.

  The camera accessory 205 can sequentially communicate with a plurality of accessories by making the intermediate accessory 40 behave similarly.

  Since the second communication connection switch 311 is open in S504 and S505, the intermediate accessory 40 and the lens control unit 113 do not receive the information transmission request transmitted from the camera control unit 205 in S502.

  In step S506, the intermediate accessory control unit 309 transmits the authentication information of the intermediate accessory 30 to the camera control unit 205 by the second communication. Then, the second communication connection switch 311 is short-circuited. Thereby, the intermediate accessory control unit 409 can receive the data transmitted by the camera control unit 205.

  When the camera control unit 205 receives the authentication information of the intermediate accessory 30 in S507, the process proceeds to S508. Then, the received authentication information is stored.

  As described above, when the authentication information of the intermediate accessory 30 is obtained in S502 to S508, the process proceeds to S509. In steps S509, S511, and S513 to S515, the camera control unit 205 acquires the authentication information of the intermediate accessory 40, as in steps S502, S503, and S506 to S508.

  In S510, the intermediate accessory control unit 309 receives the authentication information request transmitted by the camera control unit 205, but does not respond because it has not received the sub-process end information.

  In S512, as in S504 and S505, since the second communication connection switch 411 is open, the lens control unit 113 does not receive the information transmission request transmitted from the camera control unit 205 in S509.

  The first embodiment is an example in which one interchangeable lens and two intermediate accessories are connected, a total of three accessories. However, only one intermediate accessory may be connected, or three or more intermediate accessories may be connected. Since any number of intermediate accessories may be attached, it is preferable that the accessory information acquisition process be completed by acquiring accessory termination information.

  The termination information of the accessory may be obtained by another method. For example, similarly to S502 and S509, when the camera control unit 205 transmits the authentication information request assuming that the intermediate accessory is attached, the camera control unit 205 determines whether the intermediate accessory is attached to the interchangeable lens by the termination information returned from the lens second communication unit 115. You may be notified that there is. Alternatively, the intermediate accessory 40 may detect that the terminal itself is at the end based on the connection state of a terminal (not shown) or the like, and notify the camera body 20 in S513. In the present embodiment, a case will be described in which the lens control unit 113 responds to the authentication information request from the camera control unit 205 with the authentication information including the terminal information, thereby notifying the terminal information.

  In step S516, the camera body 20 transmits an authentication information request (corresponding to the second transmission request) through the second communication as in steps S502 and S509. In S517 and S518, the intermediate accessory 30 and the intermediate accessory 40 do not respond because they have not received the sub-process end information, as in S510.

  When the lens control unit 113 receives the authentication information request in S519, the process proceeds to S520, and transmits the authentication information to the camera control unit 205 by the second communication.

  Here, the authentication information transmitted by the lens control unit 113 to the camera control unit 205 will be described with reference to FIG. 910E. The authentication information includes identification information (an example of second information), operation state information, correction processing necessity information, and termination information.

  Since the interchangeable lens 10 is not an intermediate accessory, it is not necessary to correct optical information of the interchangeable lens 10 by mounting the interchangeable lens 10. Therefore, the correction processing necessity information is information indicating that the correction processing is unnecessary.

  Further, since the interchangeable lens 10 of the present embodiment is at the end of the second communication as viewed from the camera body 20, the end information is information indicating that the interchangeable lens 10 is at the end of the second communication.

  When the camera control unit 205 acquires the authentication information in S521, the process proceeds to S522, and a series of initial communication processing ends.

  In order to shorten the communication process, it is preferable to acquire the correction processing necessity information as in the present embodiment. However, when the correction information necessity information is not exchanged, the correction process is necessary in all the intermediate accessories. Judge that there is.

  With S522, the sub-process S304 ends.

  In the present embodiment, the processing using the means for sequentially communicating with a plurality of accessories using the second communication connection switch has been described in the present embodiment. However, another means may be used as long as it can communicate with a plurality of accessories. For example, by detecting the voltage level of a terminal (not shown) to which the accessory is connected, it is possible to know the order of the accessory from the camera body side. In that case, the number of information transmission requests transmitted from the camera is counted, and the information is transmitted to the camera body only when the number matches the mounting order of the camera itself.

<Sub-process S307 for determining first accessory (FIG. 6)>
In the first embodiment, the flow of the sub-process S307 in which the camera body 20 searches for the first accessory among the accessories related to the correction by communication will be described with reference to FIG.

  FIG. 6 illustrates a flow of the sub-process S307 in which the camera control unit 205 determines the first accessory among the accessories related to the optical correction in the camera system according to the first embodiment. Here, it is assumed that the camera control unit 205 does not hold optical information of the interchangeable lens 10, the intermediate accessory 30, and the intermediate accessory 40. Further, it is assumed that the correction processing necessity information of the intermediate accessory 30 and the intermediate accessory 40 is both “necessary”.

  When the sub-process starts in S601, the process proceeds to S602.

  In step S602, the camera control unit 205 transmits the identification information of the intermediate accessory 40 and the optical information presence / absence reply request to the intermediate accessory control unit 309 by the second communication, and holds the optical information of the intermediate accessory 40. Ask if it is. The method of specifying the transmission destination is, for example, by adding the identification information of the intermediate accessory to the transmission data at the beginning of the communication data, and referring to the head value of the communication data to determine whether the communication is addressed to itself. Good.

  When the intermediate accessory control unit 309 receives the identification information of the intermediate accessory 40 and the optical information presence / absence reply request in S603, the process proceeds to S604.

  In step S <b> 604, the intermediate accessory control unit 309 transmits to the camera control unit 205 whether or not the optical information of the intermediate accessory 40 is held by the second communication.

  In step S605, when the camera control unit 205 receives the presence or absence of the optical information of the intermediate accessory 40 from the intermediate accessory 30, the process proceeds to step S606.

  In step S606, the camera control unit 205 determines an intermediate accessory (also referred to as a first intermediate accessory) having optical information of another intermediate accessory.

  When the intermediate accessory control unit 309 holds the optical information of the intermediate accessory 40, the process proceeds to S607, and the camera control unit 205 determines that the intermediate accessory 30 is the first intermediate accessory.

  If the intermediate accessory control unit 309 does not hold the optical information of the intermediate accessory 40, the process proceeds to step S <b> 608. If the intermediate accessory 40 is the first intermediate accessory and holds the optical information of the intermediate accessory 30, camera control is performed. The unit 205 makes the determination.

  Even when three or more intermediate accessories are mounted, the first intermediate accessory can be similarly determined. For example, when three accessories are mounted, the same processing as S602 to S605 is performed between two accessories. When the first intermediate accessory is found, the process proceeds to S609.

  In step S609, the camera control unit 205 requests the lens control unit 113 to respond to the presence / absence of the identification information of the first intermediate accessory and the optical information (fourth information) determined in step S607 or S608 in the first communication. (Third instruction information) is transmitted. In other words, it inquires whether the optical information of the first intermediate accessory is held.

  When the lens control unit 113 receives the identification information of the first intermediate accessory and the optical information presence / absence reply request in S610, the process proceeds to S611 and determines whether the optical information of the first intermediate accessory is held in the first communication. To the camera control unit 205.

  When the camera control unit 205 receives the presence or absence of the optical information of the first intermediate accessory from the interchangeable lens 10 in S612, the process proceeds to S613, and determines whether the lens control unit 113 holds the optical information of the first intermediate accessory. Judge. Thereby, the first accessory is determined.

  If the camera control unit 205 determines that the lens control unit 113 holds the optical information of the first intermediate accessory, the process proceeds to S614. In S614, it is determined that the interchangeable lens 10 is the first accessory and holds the optical information of the intermediate accessory 30 and the intermediate accessory 40. If the camera control unit 205 determines that the lens control unit 113 does not hold the optical information of the first intermediate accessory, the process proceeds to S615.

  In S615, the camera control unit 205 determines that the first intermediate accessory is the first accessory.

  When the first accessory is determined in S614 or S615, the process proceeds to S616, and the camera control unit 205 stores the identification information and the accessory type of the first accessory. When the first accessory is stored, the process proceeds to S617, and the sub-process S307 ends.

<Effect of Embodiment 1>
As described above, in the first embodiment, the first communication path through which the camera and the interchangeable lens can communicate and the second communication path through which the camera and the accessory can communicate are independently provided. Then, the unit that corrects the optical information of the interchangeable lens is determined based on the identification information of each unit and the information on the necessity of the intermediate accessory correction processing, which are obtained by the communication using the respective communication paths. Accordingly, communication between the imaging device, the interchangeable lens, and the intermediate accessory unit can be performed at a more intended timing while appropriately correcting the optical information of the interchangeable lens.

  In the first embodiment, the method of correcting the optical information of the interchangeable lens based on the optical information of the intermediate accessory in the startup sequence immediately after the mounting of the interchangeable lens has been described. In a second embodiment, a method of correcting optical information of an interchangeable lens when an optical system of an accessory dynamically changes by operating an operation member provided on the accessory will be described.

  Examples of dynamically changing the optical system of the accessory by operating the operation member provided on the intermediate accessory include a variable power lens with a variable magnification and an ND filter with a variable transmittance.

  In the second embodiment, the processing described in the first embodiment is executed when the current optical system is determined by mounting the interchangeable lens. Accordingly, it is assumed that the camera control unit 205 has grasped a unit that holds optical information of all the accessories among the interchangeable lens 10, the camera body 20, the intermediate accessory 30, and the intermediate accessory 40.

  Also, it is assumed that the camera control unit 205 recognizes an accessory whose optical system can change dynamically based on the accessory identification information acquired by the operation as in the first embodiment.

  Hereinafter, an accessory whose optical information dynamically changes and whose correction processing necessity information is “necessary” is expressed as a dynamic accessory. An intermediate accessory whose optical information does not dynamically change and whose correction processing necessity information is “No” is referred to as a static intermediate accessory. An interchangeable lens whose optical information changes dynamically is called a dynamic lens, and an interchangeable lens whose optical information does not change dynamically is called a static lens.

  In this embodiment, an example in which the intermediate accessory 30 and the intermediate accessory 40 are mounted between the camera body 20 and the interchangeable lens 10 will be described. However, in the case where only one of the intermediate accessories is mounted. Even if there is, this embodiment is applicable.

<Dynamic accessory search processing (FIG. 7)>
FIG. 7 shows the relationship between the first embodiment and the present embodiment. When the camera system is activated in S701, the process proceeds to S702.

  In S702, the camera control unit 205 executes the processing described in FIG. That is, for example, initial communication, determination of the first unit, and correction of optical information of the interchangeable lens are executed. In the initial communication, information (also referred to as dynamic accessory information) corresponding to whether or not the optical system dynamically changes is acquired from the interchangeable lens 10, the intermediate accessories 30, and 40. For example, the camera control unit 205 transmits a transmission request to the accessory at the timing of acquiring identification information in S402 in FIG. 4 or S502 and S509 in FIG. The accessory transmits the dynamic accessory information in response to the transmission request. The authentication information may be included in the dynamic accessory information, and the authentication information including the moving body accessory information may be acquired as a response to the authentication information transmission request transmitted from the camera control unit 205 to the accessory. Note that the camera control unit 205 may determine whether or not the accessory is a dynamic accessory from the identification information of the accessory acquired in S702 without separately acquiring the dynamic accessory information. In this case, the memory (not shown) of the camera control unit 205 may be configured to have the identification information of the accessory and the information (table or the like) indicating the correspondence between whether or not the optical system dynamically changes. Accordingly, the camera control unit 205 can determine whether or not the accessory is a dynamic accessory based on the identification information of the accessory.

  When the sub-process S702 ends, the process transits to S703.

  In S703, the camera control unit 205 determines whether or not a dynamic accessory is mounted based on the above-described dynamic accessory information. More specifically, when information indicating that the optical system dynamically changes is acquired from any accessory as dynamic accessory information, the camera control unit 205 determines that the dynamic accessory is mounted. I do. If the information indicating that the optical system dynamically changes is not acquired as the dynamic accessory information, the camera control unit 205 determines that the dynamic accessory is not mounted. If a dynamic accessory has been mounted, the process proceeds to S704.

  In step S704, the camera control unit 205 executes a sub-process of correcting the optical information of the interchangeable lens based on a change in the optical information of the dynamic accessory. If the dynamic accessory is not attached or the dynamic accessory is not operated, there is no need to correct the optical information of the interchangeable lens, so the flow shifts to S705, and the optical correction processing of the interchangeable lens ends.

<Optical information correction processing according to operation of dynamic accessory (FIG. 8)>
Hereinafter, a sub-process S704 of correcting optical information of an interchangeable lens based on a change in optical information according to operation of a dynamic accessory according to a second embodiment of the present invention will be described with reference to FIG.

  In the sub-process shown in FIG. 8, it is assumed that the intermediate accessory 30 is a dynamic accessory, the interchangeable lens 10 is a first unit and a static lens, and the intermediate accessory 40 is a static intermediate accessory. That is, it is assumed that the camera control unit 205 and the lens control unit 113 have recognized as such in S702 of FIG.

  When the sequence starts in S801, the process proceeds to S802.

  In step S802, the camera control unit 205 transmits an optical data identification information transmission request to the intermediate accessory control unit 309 of the intermediate accessory 30, which is a dynamic accessory, through the second communication.

  When the intermediate accessory control unit 309 receives the optical data identification information transmission request in S803, the process proceeds to S804 and transmits the optical data identification information to the camera control unit 205 by the second communication.

  Note that the optical data identification information of the dynamic accessory is information on a parameter for correcting the optical information of the interchangeable lens 10, and in this embodiment, it is assumed that the information is, for example, current optical information. For example, when the intermediate accessory has a variable power lens, it is information on the current magnification. For example, when the intermediate accessory has an ND filter, the information is information for correcting the current optical path length. The optical data identification information may be other information as long as the first unit can recognize the optical state of the dynamic accessory. In addition, information such as a model number (ID) used for identification of a type (model) may be added with information on a plurality of possible states, or optical data identification information indicating dynamically changing optical data. It may be. Further, the information may include information indicating a function of the accessory and information such as a manufacturing number (serial number) capable of identifying an individual in the same model.

  When the camera control unit 205 receives the optical data identification information in step S805, the process proceeds to step S806.

  In S806, the camera control unit 205 determines whether the optical information of the intermediate accessory 30 has changed based on the optical data identification information. For example, the optical information of the intermediate accessory 30 received in the initial communication in S702 is compared with the optical data identification information received in S805. If the optical information has not changed, the process returns to step S802, and the camera control unit 205 retransmits the optical data identification information transmission request after a predetermined time has elapsed.

  If the camera control unit 205 determines in step S806 that the optical information of the intermediate accessory 30 has changed, the process advances to step S807 to shift to a process for correcting the optical information of the optical lens.

  The camera control unit 205 recognizes a change in optical information of the dynamic accessory by performing communication with the dynamic accessory at regular intervals by polling as in S802, 803, 804, 805, and S806. The presence or absence of a change in information may be received.

  Further, when the optical information of the dynamic accessory changes, an interrupt signal may be received from the dynamic accessory. For example, it is assumed that the intermediate accessory 30 that is a dynamic accessory has an operation member that changes optical information of the intermediate accessory 30. In this case, the operation of the operation member may be detected, and an interrupt signal may be transmitted from the later-described intermediate accessory control unit 309 to the camera control unit 205. Also, the camera control unit 205 may receive the interrupt signal from the intermediate accessory control unit 309, execute the above-described steps S802, 803, 804, and 805 after determining in S806 that the optical data identification information has changed. good.

  In addition, optical data identification information in which a change is reflected as in S802, 803, 804, and 805 may be exchanged. Alternatively, only the change in the optical data identification information may be notified to the camera control unit 205, and the camera control unit 205 may calculate the current optical data identification information and start the exchange.

  In step S807, the camera control unit 205 transmits the optical data identification information of the intermediate accessory 30 and a request to correct the optical information of the interchangeable lens 10 (also referred to as an optical correction request) through the first communication to the interchangeable lens as the first unit. To the ten lens control units 113.

  In step S808, upon receiving the optical data identification information of the intermediate accessory 30 and the optical correction request, the lens control unit 113 transitions to step S809.

  In step S809, the lens control unit 113 acquires the current optical information of the intermediate accessory 30 from the table in the lens control unit 113 based on the optical data identification information of the intermediate accessory 30, and transitions to step S809.

  In step S810, the optical information of the interchangeable lens 10 is corrected based on the optical information of the intermediate accessory 40 and the optical information of the intermediate accessory 30 which are the static intermediate accessories acquired in the sub-process S702.

  When the correction is completed, in step S811, the lens control unit 113 transmits the corrected optical information of the interchangeable lens 10 to the camera control unit 205 through the first communication.

  When the optical information of the interchangeable lens corrected by the camera control unit 205 is received in step S812, the process proceeds to step S813, and the optical information is stored in the camera control unit 205.

  When S813 ends, the process returns to S802, and the change of the optical information of the dynamic accessory is monitored again.

  In this embodiment, a case has been described in which one of the intermediate accessories is a dynamic accessory and the optical lens 10 is a first unit. In addition, even when there are a plurality of dynamic accessories or when the first unit is a unit other than the interchangeable lens, the correction process can be similarly performed.

  If only the first unit is a dynamic accessory, and if the first unit recognizes that, the optical correction is performed at the stage where it recognizes that its own optical information has changed, and the optical correction is performed. The optical data of the later interchangeable lens 10 may be transmitted to the camera body 20.

  The correction processing of the optical information of the interchangeable lens 10 is performed in consideration of not only the optical information of the dynamic accessory acquired in S805 but also the optical information of the static intermediate accessory like the optical information of the intermediate accessory 40 in S810. . When the static intermediate accessory is mounted, correction is performed in advance using the optical information of the static intermediate accessory, and when the optical information dynamically changes, final correction processing is performed using the optical information of the dynamic accessory. You may.

<Effect of Embodiment 2>
As described above, in the second embodiment, the camera control unit 205 detects a change in the optical information of the intermediate accessory 30. Then, the camera body 20 transmits information on the change in the optical information and a request for correcting the optical information of the interchangeable lens 10 to the lens control unit 113. Then, the lens controller 113 corrects the optical information of the interchangeable lens 10 and transmits the information to the camera controller 205.

  Thus, even when the optical information of the accessory dynamically changes, the optical information of the interchangeable lens can be appropriately corrected.

  In the present embodiment, description will be made focusing on a case where optical data identification information indicating optical data unique to an accessory is used as intermediate accessory identification information.

  The product-specific information, such as the model number (ID), of the intermediate accessory identification information indicates that the accessory of the new product has the same optical system as the known accessory or that the accessory can be corrected by the same correction method as the known accessory. However, a new model number is assigned. Therefore, when the necessity of correcting the optical information of the interchangeable lens is determined based on the model number (ID) or the like, if the model number (ID) is unknown, the optical characteristics of the lens are considered in consideration of the optical characteristics of the accessory. The information could not be corrected.

  Therefore, in the present embodiment, optical data identification information is used as intermediate accessory identification information. In the present embodiment, the intermediate accessory identification information is linked to the correction method. More specifically, a combination of information on a correction method and information on a correction parameter is defined as optical data identification information. Such optical data identification information is hereinafter referred to as correction identification information. The information on the correction method according to the present embodiment is information corresponding to the optical member of the intermediate accessory, and the information on the correction parameter is information corresponding to the optical information of the intermediate accessory based on the optical characteristics of the optical member. Taking the case where the intermediate accessory is a variable power adapter having a variable power lens as an example, the information on the correction method is information indicating the variable power lens, and the information on the correction parameters is magnification information on the variable power lens.

  The lens control unit 113 may be configured to store information on a correction method and information on a correction parameter in association with each other. If other information is necessary for correcting the optical information, the information may be stored in association with the information on the correction method and the information on the correction parameter.

  As described above, information on the correction method and information on the correction parameters are transmitted to the lens control unit 113 via the camera control unit 205. Thus, even if it is necessary to perform a correction in consideration of an intermediate accessory having different information on the correction parameter, the magnification information as the correction parameter is reset, and the existing unit (the interchangeable lens 10 in this embodiment) is set. Can be corrected.

  As described above, by using the optical data identification information, the optical information of the interchangeable lens can be corrected in consideration of the optical characteristics of the accessory. For example, if the camera has an optical system similar to an existing product, or is an accessory that can be corrected in the same manner as an existing product, and the model number (ID) is unknown, the optics of the interchangeable lens are unknown. The information can be corrected.

  When the correction identification information is used, it is not efficient to store the correction algorithm in each unit. Therefore, it is preferable to previously determine the unit to perform the correction. In this embodiment, a case will be described in which the unit for performing the correction is determined to be an interchangeable lens in advance. A method of correcting an interchangeable lens when the correction identification information is used will be described. In the case where correction is performed by the first unit as in the first and second embodiments, the correction identification information can be used similarly.

<Process of Obtaining Corrected Optical Information in Third Embodiment (FIG. 10)>
FIG. 10 shows that, when power is supplied for the first time after mounting each accessory, the camera body 20 acquires correction information from each accessory, transmits it to the interchangeable lens 10 and requests correction, and 10 shows a flow of a process of acquiring ten optical information.

  When the camera body 20 is activated in S1001, the process proceeds to S1002.

  In step S1002, the camera body 20 supplies power to the interchangeable lens 10, the intermediate accessory 30, and the intermediate accessory 40 via a power supply mounting contact (not shown), and the process proceeds to step S1003.

  The sub-process S1003 which is the initial communication process with the accessory by the second communication is substantially the same as the sub-process S304 in the first embodiment. In S1003, the above-described correction identification information is acquired as identification information of the intermediate accessory.

  Upon acquiring the correction authentication information of the accessory in S1003, the process proceeds to S1004.

  In step S1004, the camera control unit 205 transmits the intermediate accessory correction identification information acquired in step S1003 to the interchangeable lens 10, and requests correction of optical information. When the interchangeable lens acquires the correction identification information of the intermediate accessory, the process proceeds to S1005.

  In step S1005, the interchangeable lens control unit 113 determines whether it is necessary to correct its own optical information based on the intermediate accessory correction identification information. If an intermediate accessory requiring correction of optical information has been mounted, the flow shifts to S1006.

  In step S1006, the interchangeable lens control unit 113 corrects its own optical information based on the intermediate accessory correction identification information, and transmits the corrected optical information to the camera.

  In S1005, if the intermediate accessory is not attached, or if all the attached intermediate accessories are intermediate accessories that do not require correction of the optical information of the interchangeable lens, there is no need for correction processing. Transitions to.

  In S1007, the interchangeable lens control unit 113 transmits its own optical information to the camera.

  The transmission timing of the optical information in S1006 and S1007 may be immediately after the correction is completed, or may be the timing requested by the camera.

  After acquiring the optical information in S1006 or S1007, the process transits to S1008, and the optical information acquisition sequence ends.

  In this manner, in a camera system having a first communication path through which the camera and the interchangeable lens can communicate and a second communication path through which the camera and the intermediate accessory can communicate independently, the camera system can be replaced based on optical information of the intermediate accessory. The optical information of the lens can be appropriately corrected.

  Further, in the first embodiment, the example has been described in which the accessory authentication information includes the accessory identification information and the correction processing necessity information. On the other hand, the authentication information of the accessory may include only the correction processing necessity information, and the correction processing necessity information may be separately acquired when the correction processing necessity information indicates the correction “necessary”. good. This makes it possible to reduce the amount of communication in the case where the correction processing necessity information indicates the correction “no”, as compared with the case where the correction identification information is acquired regardless of the necessity of the correction processing necessity information. is there. In this case, as in the above-described embodiment, both the intermediate accessory identification information and the correction processing necessity information are acquired. That is, when the correction processing necessity information is the correction "necessary" and the correction identification information is separately obtained, both the intermediate accessory identification information and the correction identification information are obtained as the information for identifying the accessory. This reduces the amount of communication when the correction processing necessity information indicates the correction “no”, and the intermediate accessory irrespective of whether the correction processing necessity information is the correction “necessary” or “no”. The identification information can be used for another purpose.

  If the lens control unit 113 determines that the information corresponding to the information on the correction method is not stored based on the information on the correction method included in the correction identification information, the optical information of the interchangeable lens 10 is stored. Control may be performed so that correction is not performed.

<Effect of Embodiment 3>
As described above, the camera control unit 205 acquires information on the correction method and information on the correction parameters from the intermediate accessory control unit 309, and transmits the information to the lens control unit 113. As a result, the lens control unit 113 can correct optical information in consideration of the accessory if the correction method is known, even if the accessory is a new accessory.

  In the above embodiment, the camera body 20 acquires the identification information of the interchangeable lens 10 (also referred to as first lens identification information) as the authentication information of the interchangeable lens 10 in the initial communication performed with the interchangeable lens 10 in the first communication. That was explained. Further, it has been described that the camera body 20 acquires the identification information of the interchangeable lens 10 (also referred to as second lens identification information) as the authentication information of the interchangeable lens 10 in the initial communication performed with the accessory in the second communication. In the present embodiment, an embodiment focusing on the relationship between the first lens identification information and the second lens identification information will be described.

  As described above, the identification information of the interchangeable lens 10 and the accessory may be information such as a model number (ID) used for identifying the type (model) of the corresponding unit. Further, the information may include information indicating a function of the interchangeable lens or information such as a manufacturing number (serial number) capable of identifying an individual in the same model.

  Here, in the camera system of the present embodiment, the interchangeable lens 10 can communicate with the camera body 20 by both the first communication and the second communication, and as described in the first embodiment, the first communication and the Initial communication with the camera body 20 is performed by both of the two communications. The interchangeable lens 10 transmits the identification information of the interchangeable lens 10 (the above-described first lens identification information and second lens identification information) to the camera body 20 in both the first communication and the second communication. .

  At this time, the lens control unit 113 may send the same information as the first lens identification information and the second lens identification information. However, in this embodiment, the lens control unit 113 dares to use the first lens identification information as the second lens identification information. Information different from the information is transmitted to the camera control unit 205. Thus, the second lens identification information transmitted from the lens control unit 113 to the camera control unit 205 through the second communication is effectively used.

  The first lens identification information and the second lens identification information of the present embodiment will be described more specifically. The first lens identification information is information that enables the type (model) of the interchangeable lens 10 to be identified, and is, for example, a model number (ID).

  On the other hand, the second lens identification information is different from the first lens identification information. For example, the second lens identification information is information indicating that the interchangeable lens 10 is a lens. In this case, the second lens identification information is merely information indicating that the interchangeable lens 10 is a lens, and does not correspond to the type (model) of the interchangeable lens 10. Accordingly, for example, the second lens identification information can be unique information that does not depend on the type (model) of the interchangeable lens 10.

  As described above, in the present embodiment, the lens control unit 113 transmits the first identification information transmitted in the initial communication of the first communication, which is a one-to-one communication between the camera body 20 and the interchangeable lens 10, to the camera body 20 It is not transmitted in the second communication assuming one-to-many communication with each accessory. In the second communication, information indicating that the lens is a lens, in other words, information indicating that the lens is not an intermediate accessory, is transmitted to the camera control unit 105 as second identification information.

  In the present embodiment, by using the first lens identification information and the second lens identification information properly as described above, for example, the following effects can be realized.

  For example, the identification information obtained by the camera control unit 205 from the lens control unit 113 in the first communication is used as a system for the interchangeable lens, and the identification information obtained by the camera control unit 205 from the control unit of each accessory in the second communication is intermediate. It can be treated as a system for accessories. This makes it possible to provide a camera system that has expandability for intermediate accessories that may appear in the future.

  Also, for example, it can be used to grasp the number of intermediate accessory connections. This is because an accessory that transmits identification information other than the second identification information to the camera control unit 105 is not the interchangeable lens 10, and thus can be determined to be an intermediate accessory.

  When the number of connected intermediate accessories is grasped, for example, when a predetermined number or more of the intermediate accessories are attached, a warning operation to the user may be performed, or the function of any of the intermediate accessories may be restricted. Is also good. This makes it possible to reduce power consumption and maintain communication quality. When a large amount of data is transmitted to the intermediate accessory such as firmware up, the transition to the firmware up mode of the intermediate accessory may be permitted only when it is determined that only one intermediate accessory is connected. .

  Further, by determining that the interchangeable lens 10 is not an intermediate accessory but a lens, information to be transmitted from the lens control unit 113 to the camera control unit 105 in the initial communication of the second communication can be reduced. . For example, the correction processing necessity information may not be responded from the lens control unit 113 to the camera control unit 105. This is because the optical information of the interchangeable lens 10 need not be corrected by mounting the interchangeable lens 10 that is not an intermediate accessory.

  Further, for example, the following may be used to electrically determine whether the terminal accessory is an interchangeable lens or an intermediate accessory, and compare the determination result with the second identification information. The details will be described below. As described above, a communication error can be determined by checking the consistency with the hardware processing.

  In the present embodiment, an example of a method of electrically determining whether the terminal accessory is an interchangeable lens or an intermediate accessory in the initial communication with the interchangeable lens or the intermediate accessory in the first to fourth embodiments will be described. Further, an error process when the discrimination result is inconsistent with the accessory at the end of the second communication, which is determined based on the identification information acquired by the second communication, will be described.

<Configuration of Camera System in Embodiment 4 (FIGS. 12 and 13)>
Hereinafter, an example of a method of electrically determining whether the terminal accessory is an interchangeable lens or an intermediate accessory will be described. Note that this determination is made in the initial communication of the second communication.

  First, a configuration in the case where the interchangeable lens 10 is mounted at the end of the second communication will be described. As shown in FIG. 1218, the mount 201 of the camera body 20 includes an identification terminal 212. The mount 302 of the intermediate accessory 30 includes the identification terminal 313, and the mount 302 includes the identification field factor 313. The mount 402 of the intermediate accessory 40 includes the identification terminal 413, and the mount 401 includes the identification terminal 412. The mount 101 of the interchangeable lens 10 includes an identification terminal. Lines (also referred to as identification lines) connected via these identification terminals are connected to a resistor 118 provided on the interchangeable lens 10. This line is connected to a pull-up through a resistor 213 provided in the camera body 20. A value obtained by dividing the voltage level of the pull-up power supply by each resistance value of the resistor 118 and the resistor 213 is input to the camera control unit 205.

  Next, a configuration in the case where the end of the second communication is the intermediate accessory 40 will be described. As shown in FIG. 13, the identification line via the identification terminals 212, 313, 312, and 413 is connected to the resistor 414 provided on the intermediate accessory 40, as in the case where the end of the second communication is an interchangeable lens. ing. The input to the camera control unit 205 is a value obtained by dividing the voltage level of the pull-up power supply of the camera body 20 by the resistance values of the resistor 414 and the resistor 213.

<Second Communication Error Determination Method in Fourth Embodiment (FIG. 15)>
Here, the resistance value of the resistor used for the interchangeable lens 10 and the resistance value of the resistor used for the intermediate accessory at the end are defined so as to be different values in advance. This makes it possible to electrically determine whether or not the terminal accessory is an interchangeable lens based on the level of the input signal via the identification terminal.

  When the terminal accessory electrically determined is the interchangeable lens 10, the second identification information should be obtained as the terminal accessory identification information acquired in the initial communication by the second communication. On the other hand, if the terminal accessory electrically determined is the intermediate accessory, the identification information of the terminal accessory acquired in the initial communication by the second communication should be different from the second identification information, Specifically, it should be intermediate accessory identification information.

  However, if any problem occurs in the second communication, the above-mentioned correspondence may be inconsistent. Therefore, when there is an inconsistency between the electrically determined terminal accessory and the identification information acquired by the second communication, it is determined that a communication error has occurred, and a more accurate communication is performed by retrying from the initial communication. be able to.

  As described above, by comparing the electrical identification information with the identification information acquired by the second communication, it is possible to confirm whether the communication has been correctly performed in the second communication. It can be determined whether the acquired identification information is correct. This makes it possible to detect a communication error of the second communication.

<Effect of Embodiment 4>
As described above, in the present embodiment, the second lens identification information is information that is different from the first lens identification information corresponding to the type (model) of the interchangeable lens 10 and indicates that the lens is a lens. And Thereby, for example, it is possible to further improve the identification performance of the accessory that performs communication by the second communication.

<Other Examples>
In the above-described embodiment, the first accessory has been described as an accessory that holds optical information of all other accessories among the accessories related to the correction. However, among accessories related to correction, an accessory having the most optical information of each other may be used. That is, there may be an accessory having no optical information. In this case, in this case, the missing optical information may be obtained from another unit.

  In the initial communication of the above-described embodiment, the lens control unit 113 transmits the identification information of the interchangeable lens 10 in S404 and S520. Here, for example, the identification information transmitted in S520 may be identification information indicating that it is not an intermediate accessory.

  In addition, in the initial communication of FIG. 5 in the above-described embodiment, each accessory transmits a plurality of pieces of information as authentication information to the camera control unit 205, but only the necessary information may be transmitted. In this case, the camera specifies the necessary information and transmits an information request to each accessory.

  Further, in the above-described embodiment, the case where the number of intermediate accessories is two has been described. However, in the case of three or more, whether all of the optical information of the other intermediate accessories among the plurality of intermediate accessories is included, It is assumed that what has more is the first intermediate accessory.

  In the second embodiment, the dynamic accessory may correct the optical information of the interchangeable lens 10. In this case, the dynamic accessory may acquire the optical information of another accessory in advance. When the dynamic accessory corrects the optical information of the interchangeable lens 10, the corrected accessory transmits the corrected optical information to the camera body 20.

  In the second embodiment, when there are a plurality of first accessories, the dynamic accessory may correct the optical information of the interchangeable lens 10.

  In the third embodiment, the case where the optical information of the optical lens 10 is corrected in the camera body 20 has been described. On the other hand, optical information may be corrected in the interchangeable lens 10. In this case, the camera control unit 205 transmits a request for correcting the optical information of the interchangeable lens 10 to the lens control unit 113. At this time, if the optical information of the intermediate accessory that needs to be corrected is insufficient, the interchangeable lens 10 may acquire the optical information of the intermediate accessory from the camera body 20 or the intermediate accessory as needed. .

  Fourth Embodiment In the fourth embodiment, an example has been described in which the camera control unit 205 acquires information on a correction method and information on a correction parameter from the intermediate accessory control unit 309, and transmits the information to the lens control unit 113. Here, when the intermediate accessory 30 is a dynamic intermediate accessory as described in the second embodiment and the information on the correction parameter can change, the information on the correction parameter is reacquired in accordance with the detection of the change. You may. That is, when it is detected that the operation member of the intermediate accessory 30 has been operated, the camera control unit 205 acquires information on correction parameters from the intermediate accessory control unit 309 and transmits the information to the lens control unit 113. You may do it.

  Further, in the first embodiment, the case where clock synchronous communication is performed as the first communication method has been described, but start-stop synchronous communication may be performed. The start-stop synchronous communication will be described with reference to FIG.

  FIG. 2 exemplifies a case where three-wire clock synchronous communication is performed. Instead, the same effect can be achieved even when the three-wire start-stop synchronous communication realized by using the three wires of the communication channel 1 is adopted. FIG. 1217 shows a signal waveform in the communication of the three-wire start-stop synchronous communication. In the case of three-wire asynchronous communication, an RTS communication line (RTS) is provided instead of the above-described clock communication line (LCLK). The RTS communication line is a signal line for transmitting a signal for controlling timing of communication by the camera-lens communication line (DCL) and communication timing by the first lens-camera communication line (DLC) from the camera microcomputer 205 to the lens microcomputer 111. It is. For example, it is used for notification of a request for transmission (transmission instruction) of lens data from the camera microcomputer 205 to the lens microcomputer 111, a request for switching communication processing (switching instruction) described later, and the like. The notification on the transmission request channel is performed by switching the signal level (voltage level) on the transmission request channel between High (first level) and Low (second level). In the following description, a signal supplied to the RTS communication line is called a transmission request signal RTS. The transmission request signal RTS is sent from the camera microcomputer 205 as a communication master to the lens microcomputer 111 as a communication slave. When the lens microcomputer 111 receives the transmission request RTS, the signal level of the lens data signal DLC is set to Low for one bit period to notify the camera microcomputer 205 of the start of transmission of one frame of the lens data signal DLC. This one bit period is called a start bit ST indicating the start of one frame. That is, a data frame is started from the start bit ST. The start bit ST is provided at the head bit of each frame of the lens data signal DLC. Subsequently, the lens microcomputer 111 transmits 1-byte lens data in the next 8-bit period from the second bit to the ninth bit. The bit arrangement of the data is MSB first format, starting from the highest data D7, continuing to data D6 and data D5, and ending with the lowest data D0. Then, the lens microcomputer 111 adds 1-bit parity information PA to the 10th bit, and sets the signal level of the lens data signal DLC during the stop bit SP indicating the end of one frame to High. Thus, the data frame period started from the start bit ST ends.

  The fifth embodiment will be described focusing on the second communication in the above-described embodiment. The first communication and the second communication in the present embodiment are executed in the second communication performed by the second communication path in the aforementioned embodiment.

  FIG. 16 shows the configuration of the fifth embodiment of the present invention. In a fifth embodiment, an imaging system (hereinafter, referred to as a camera system) in which a plurality of accessory devices including an interchangeable lens 5100 and an intermediate adapter 5300 are detachably and communicably mounted on a camera body 5200 as an imaging device will be described.

  Note that the interchangeable lens 5100 may be mounted directly on the camera main body 5200 (without the intermediate adapter 5300), or two or more intermediate adapters may be mounted between the camera main body 5200 and the interchangeable lens 5100. .

  In this camera system, control commands and internal information are communicated between the camera body 5200, the interchangeable lens 5100, and the intermediate adapter 5300 using a plurality of communication circuits (communication paths). Also, in this camera system, optimal communication can be always performed in various situations by switching multiple communication circuits to the same communication mode in synchronization with each other according to the type of data to be communicated and the purpose of communication. it can.

  The interchangeable lens 5100 and the intermediate adapter 5300 are mechanically and electrically connected via a mount 5010 as a coupling mechanism. Similarly, the intermediate adapter 5300 and the camera body 5200 are mechanically and electrically connected via a mount 5011 which is a coupling mechanism. The interchangeable lens 5100 and the intermediate adapter 5300 obtain power from the camera body 5200 via power supply terminals (not shown) provided on the mounts 5010 and 5011, respectively. As a result, power necessary for the operation of various actuators and a lens microcomputer (hereinafter, referred to as a lens microcomputer 5) 5111 and an adapter microcomputer (hereinafter, referred to as an adapter microcomputer 5) 5302 to be described later is supplied.

  In addition, the interchangeable lens 5100, the camera body 5200, and the intermediate adapter 5300 perform first communication as “one-to-many” communication via communication terminals 5012, 5013 provided on the mounts 5010, 5011. Further, the interchangeable lens 5100, the camera body 5200, and the intermediate adapter 5300 perform a second communication different from the first communication via communication terminals 5014 and 5015 provided on the mounts 5010 and 5011. The second communication is not “one-to-many” communication, but “one-to-one” communication such as clock-synchronized serial communication or UART communication. In the present embodiment, two types of communication, that is, first and second communication are performed, but the number of types of communication may be three or more.

  The interchangeable lens 5100 has an imaging optical system. The imaging optical system includes, in order from the object OBJ, a field lens 5101, a zoom lens (magnifying lens) 5102 for performing magnification, an aperture unit 5114 for adjusting the amount of light, an anti-vibration lens 5103, and a focus lens 5104 for adjusting focus. . The zoom lens 5102 and the focus lens 5104 are held by lens holding frames 5105 and 5106, respectively. The lens holding frames 5105 and 5106 are guided by a guide shaft (not shown) so as to be movable in the optical axis direction in which the optical axis (indicated by a broken line in the drawing) extends, and are driven in the optical axis direction by stepping motors 5107 and 5108. You. The stepping motors 5107 and 5108 respectively move the zoom lens 5102 and the focus lens 5104 in synchronization with the driving pulse.

  The anti-vibration lens 5103 is shifted and driven in a direction orthogonal to the optical axis of the imaging optical system by an anti-vibration actuator 5126 such as a voice coil motor. As a result, an image stabilizing operation for reducing image shake caused by camera shake such as camera shake is performed. The aperture unit 5114 is provided with aperture blades 5114a and 5114b, and drives the aperture blades 5114a and 5114b in the opening and closing directions to adjust the amount of light. The positions of the aperture blades 5114a and 5114b are detected by the Hall element 115 and input to the lens microcomputer 5111 via the amplification circuit 5122 and the A / D conversion circuit 5123.

  The interchangeable lens 5100 has a lens electronic ring 5130 as an operation member. The user can rotate the lens electronic ring 5130 around the optical axis, and the amount and direction of the rotation are detected by a rotation detector 5131 such as a photo interrupter and input to the lens microcomputer 5111. The operation member may be a switch, a button, a dial, or a touch panel, and the interchangeable lens 5100 may include a plurality of operation members.

  A lens microcomputer 5111 as an accessory control unit controls the operation of each unit in the interchangeable lens 5100. The lens microcomputer 5111 transmits a control command or transmission request transmitted from the camera body 5200 via the lens first communication circuit 5141 for performing the first communication or the lens second communication circuit 5142 for performing the second communication. Receive a command. The lens microcomputer 5111 performs lens control corresponding to the control command, and transmits lens data (accessory data) corresponding to the transmission request command to the camera body 5200 via the first and second lens communication circuits 5141 and 5142. I do. The lens microcomputer 5111 transmits corresponding lens data to the camera body 5200 according to the operation of each unit in the interchangeable lens 5100. The lens first and second communication circuits 5141 and 5142 constitute an accessory communication unit in the interchangeable lens 5100.

  Further, the lens microcomputer 5111 outputs a drive signal to the zoom drive circuit 5119 and the focus drive circuit 5120 in accordance with a command relating to zooming or focus adjustment among control commands and operation of an operation member to drive the stepping motors 5107 and 5108. Thus, zoom control for controlling zooming by the zoom lens 5102 and focus control for controlling focus adjustment by the focus lens 5104 are performed.

  In addition, the lens microcomputer 5111 is connected via a vibration-proof drive circuit 5125 in response to a vibration-related command among the control commands or a camera shake detected by a shake sensor (not shown) such as a vibration gyro provided in the interchangeable lens 5100. Then, the anti-vibration actuator 5126 is driven. Accordingly, image stabilization control for controlling shift driving of the image stabilization lens 5103 is performed.

  In addition, the lens microcomputer 5111 outputs a drive signal to the aperture drive circuit 5121 in accordance with a command related to light amount adjustment among control commands or an operation of an operation member to drive the aperture actuator 5113. Thus, light amount adjustment control for controlling the aperture unit 5114 is performed.

  The intermediate adapter 5300 is, for example, a teleconverter or a wide converter for changing the focal length, and has a variable power lens 301 and an adapter microcomputer (hereinafter, referred to as an adapter microcomputer 5) 5302 added to the imaging optical system. An intermediate adapter other than the tele or wide converter, for example, a mount converter that changes the flange back length may be used.

  The intermediate adapter 5300 has an adapter electronic ring 5310 as an operation member. The user can rotate the adapter electronic ring 5310 around the optical axis, and the amount and direction of rotation are detected by a rotation detector 5311 such as a photo interrupter and input to the adapter microcomputer 5302. The operation member may be a switch, a button, a dial, or a touch panel, and the intermediate adapter 5300 may include a plurality of operation members.

  Adapter microcomputer 5302 as an accessory control unit controls the operation of each unit in intermediate adapter 5300. The adapter microcomputer 5302 transmits a control command or transmission request transmitted from the camera body 5200 via the adapter first communication circuit 5341 for performing the first communication or the adapter second communication circuit 5342 for performing the second communication. Receive a command. The adapter microcomputer 5302 performs intermediate adapter control corresponding to the control command, and transmits adapter data (accessory data) corresponding to the transmission request command to the camera body 5200 via the adapter first and second communication circuits 5341 and 5342. Or Further, adapter microcomputer 5302 transmits corresponding adapter data to camera body 5200 according to the operation of each unit in intermediate adapter 5300. The adapter first and second communication circuits 5341 and 5342 constitute an accessory communication unit in the intermediate adapter 5300.

  The camera body 5200 includes an imaging element 5201 such as a CCD sensor or a CMOS sensor, an A / D conversion circuit 5202, a signal processing circuit 5203, a recording unit 5204, a camera microcomputer (hereinafter, referred to as a camera microcomputer 5) 5205, and a display unit 5206. .

  The imaging element 5201 photoelectrically converts a subject image formed by the imaging optical system and outputs an electric signal (analog signal). The A / D conversion circuit 5202 converts an analog signal from the image sensor 5201 into a digital signal. The signal processing circuit 5203 performs various image processing on the digital signal from the A / D conversion circuit 5202 to generate a video signal. The signal processing circuit 5203 also generates focus information indicating the contrast state of the subject image (the focus state of the imaging optical system) and luminance information indicating the exposure state from the video signal. The signal processing circuit 5203 outputs a video signal to the display portion 5206. The display unit 5206 displays the video signal as a live view image used for checking a composition, a focus state, and the like.

  A camera microcomputer 5205 serving as a camera control unit controls the operation of each unit in the camera body 5200 in accordance with an input from a camera operation member such as an imaging instruction switch and various setting switches (not shown). For example, the exposure time of the image sensor 5201 is controlled for exposure control, and the sensitivity of the A / D conversion circuit 5202 is controlled.

  In addition, the camera microcomputer 5205 sends control commands and commands to the interchangeable lens 5100 and the intermediate adapter 5300 via the camera first communication circuit 5241 for performing the first communication or the camera second communication circuit 5242 for performing the second communication. Send the transmission request command. For example, the camera microcomputer 5205 transmits a control command related to zoom control of the zoom lens 5102 to the interchangeable lens 5100 and the intermediate adapter 5300 in response to operation of a zoom switch (not shown). In addition, a control command related to light amount adjustment control according to luminance information and a control command related to focus control according to focus information are transmitted to the interchangeable lens 5100. The camera first and second communication circuits 5241 and 5242 constitute a camera communication unit.

  Further, the camera microcomputer 5205 receives the lens data from the interchangeable lens 5100 and the adapter data from the intermediate adapter 5300. Also, the camera microcomputer 5205 sends control commands related to these to the interchangeable lens 5100 and the operation member according to the operation information of the operation member included in the lens data or the adapter data obtained via the camera first and second communication circuits 5241 and 5242. The data is transmitted to the intermediate adapter 5300.

  In addition, the camera microcomputer 5205 transmits a transmission request command for acquiring control information and status information to the interchangeable lens 5100 and the intermediate adapter 5300 as necessary.

  Next, a communication circuit for performing first communication (“one-to-many” communication) between the camera body 5200, the interchangeable lens 5100, and the intermediate adapter 5300 will be described with reference to FIG. Note that the communication circuit described below is merely an example, and any communication circuit capable of performing “one-to-many” communication may have a configuration other than the following configuration.

  The first communication is performed by the camera microcomputer 5205 via the camera first communication circuit 5241, the lens microcomputer 5111 via the lens first communication circuit 5141, and the adapter microcomputer 5302 via the adapter first communication circuit 5341. The camera first communication circuit 5241, the lens first communication circuit 5141, and the adapter first communication circuit 5341 are connected to signal lines (CS and DATA described later) connected via communication terminal portions 5012 and 5013 provided on the mounts 5010 and 5011. 1) to perform the first communication. The camera first communication circuit 5241 includes a ground switch 52081 and an input / output changeover switch 52082. The lens first communication circuit 5141 includes a ground switch 51121 and an input / output switch 51122. The adapter first communication circuit 5341 includes a ground switch 53031 and an input / output switch 53032.

  The signal line includes a signal line CS (first signal line) for transmitting a signal for controlling communication and a signal line DATA (second signal line) for transmitting data to be transmitted and received. . The signal line CS is connected to the camera microcomputer 5205, the adapter microcomputer 5302, and the lens microcomputer 5111, and can detect the state (Hi / Low) of the signal line CS. The signal line CS is connected to a power supply (not shown) in the camera body 5200 by a pull-up connection, and via a ground switch 51121 of the interchangeable lens 5100, a ground switch 52081 of the camera body 5200, and a ground switch 53031 of the intermediate adapter 5300. Connected to GND. That is, open drain connection is possible.

  With this configuration, the state of the signal line CS of the interchangeable lens 5100, the camera body 5200, and the intermediate adapter 5300 can be set to Low by turning on (connecting) the respective ground switches. On the other hand, when the interchangeable lens 5100, the camera body 5200, and the intermediate adapter 5300 all turn off (cut off) their respective ground switches, the state of the signal line CS can be set to Hi. The details of the control signal and the operation procedure propagated using the signal line CS during communication will be described later.

  The signal line DATA is a single bidirectional data transmission line that can be used while switching the data propagation direction. The signal line DATA can be connected to the lens microcomputer 5111 via the input / output switch 51122, the transmission buffer 51123, and the reception buffer 51124 of the interchangeable lens 5100. The signal line DATA can be connected to the camera microcomputer 5205 via the input / output switch 52082, the transmission buffer 52083, and the reception buffer 52084 of the camera body 5200. Further, the signal line DATA can be connected to the adapter microcomputer 5302 via the input / output changeover switch 53032, the transmission buffer 53033, and the reception buffer 53034 of the intermediate adapter. The camera microcomputer 5205, the lens microcomputer 5111, and the adapter microcomputer 5302 operate the respective input / output change-over switches 52082, 51122, and 53032 to connect the signal line DATA to the transmission buffers 51123, 52083, and 53033, or to connect to the reception buffers 51024 and 52084. , 53034.

  With this configuration, when the camera microcomputer 5205, the lens microcomputer 5111, and the adapter microcomputer 5302 transmit data, the camera microcomputer 5205, the lens microcomputer 5111, and the adapter microcomputer 5302 connect to the transmission buffers 51123, 52083, and 53033. , 51122, 53032. Thereby, data transmission becomes possible. On the other hand, when the camera microcomputer 5205, the lens microcomputer 5111, and the adapter microcomputer 5302 receive the data, the respective microcomputers 52082 and 51122 connect the signal lines DATA to the receiving buffers 51024, 52804, and 53034, respectively. , 53032. Thereby, data reception becomes possible. The transmission buffers 51123, 52083, and 53033 and the reception buffers 51024, 52084, and 53034 have a configuration in which transmission and reception can be performed continuously within a range that can be accommodated in each buffer size. The details of the input / output switching procedure of the signal line DATA during communication will be described later.

  The configuration of the communication circuit shown in FIG. 17 is merely an example, and another configuration may be used. For example, the signal line CS is pulled down to GND in the camera body 5200, and is connected to a power supply (not shown) via the ground switch 51121 of the interchangeable lens 5100, the ground switch 52081 of the camera body 5200, and the ground switch 53031 of the intermediate adapter 5300. A possible configuration may be adopted. Alternatively, the signal line DATA may be always connected to each data input unit, and the connection / disconnection between the signal line DATA and each data output unit may be switched by a switch.

  Next, referring to the signal waveforms shown in FIG. 18, the first communication (“one-to-many” communication) is exchanged between the camera body 5200, the interchangeable lens 5100, and the intermediate adapter 5300 using the signal line DATA. The format of the communication data will be described. This format is common to a broadcast communication mode as a first communication mode and a P2P communication mode as a second communication mode, which will be described later. The format of the communication data is based on so-called start-stop synchronous communication in which transmission and reception are performed at a communication bit rate in accordance with a communication speed defined in advance between each other.

  First, in a non-transmission state in which data transmission is not performed, the signal level is maintained in a Hi state. Next, in order to notify the data receiving side of the start of data transmission, the signal level is set to the Low level for one bit period. This one bit period is called a start bit ST. Subsequently, 1-byte data is transmitted in the next 8-bit period from the second bit to the ninth bit. According to the MSB first format, the bit arrangement of the data starts from the highest-order data D7, continues to data D6, data D5, data D4, data D3, data D2, data D1, and ends with the lowest data D0. Subsequently, 1-bit parity PA information is added to the 10th bit, and the signal level is set to Hi during the last stop bit SP indicating the end of the transmission data. As a result, starting from the start bit ST, the frame period 51 ends.

  Note that the communication data format shown in FIG. 18 is merely an example, and another communication data format may be adopted. For example, the bit arrangement of the data may be LSB first or 9 bits long, and the parity PA information need not be added to the data. Further, the data format may be switched between broadcast communication as a first communication mode and P2P communication as a second communication mode, which will be described later.

  Next, referring to the signal waveforms shown in FIGS. 19A and 19B, the first communication is performed between the camera body 5200, the interchangeable lens 5100, and the intermediate adapter 5300 using the signal line CS and the signal line DATA. The broadcast communication to be performed will be described. In the broadcast communication, “one-to-many” simultaneous transmission is performed in which data is simultaneously transmitted from one of the camera microcomputer 5205, the lens microcomputer 5111, and the adapter microcomputer 5302 to the other.

  FIG. 19A shows a case where broadcast communication is performed from the adapter microcomputer 5302 to the camera microcomputer 5205 and the lens microcomputer 5111 in response to broadcast communication from the camera microcomputer 5205 to the lens microcomputer 5111 and the adapter microcomputer 5302, for example.

  First, the camera microcomputer 5205 serving as a communication master starts low output to the signal line CS in order to notify the lens microcomputer 5111 and the adapter microcomputer 5302 serving as communication slaves that broadcast communication is started (5401). Next, the camera microcomputer 5205 stores the data to be transmitted in the transmission buffer 52083, and outputs the data to the signal line DATA according to the above-described communication format at the start of transmission (5402). On the other hand, the lens microcomputer 5111 and the adapter microcomputer 5302 start outputting Low to the signal line CS at the timing when the start bit ST input from the signal line DATA is detected (5403, 5404). At this point, since the camera microcomputer 5205 has already started outputting Low to the signal line CS, the signal level propagated to the signal line CS does not change.

  Next, after completing the output of the stop bit SP of the final data, the camera microcomputer 5205 releases the Low output to the signal line CS (5405). On the other hand, the lens microcomputer 5111 and the adapter microcomputer 5302 store data in the reception buffers 51124 and 53034 every time the stop microcomputer SP receives the stop bit SP input from the signal line DATA. Then, when Low is detected on the signal line CS, data is taken out from the reception buffers 51124 and 53034, and internal processing is performed on the data. Further, after the preparation for receiving the next data is completed, the Low output to the signal line CS is released (5406, 5407). As described above, the signal level of the signal line CS becomes Hi when all of the camera microcomputer 5205, the lens microcomputer 5111, and the adapter microcomputer 5302 cancel the Low output to the signal line CS. Therefore, the camera microcomputer 5205, the lens microcomputer 5111, and the adapter microcomputer 5302 confirm that the signal level of the signal line CS becomes Hi after releasing the Low output to the signal line CS, respectively. As a result, the camera microcomputer 5205, the lens microcomputer 5111, and the adapter microcomputer 5302 can each determine that the processing related to the current communication has been completed and the preparations for performing the next communication have been completed.

  Next, after confirming that the signal level of the signal line CS has returned to Hi, the adapter microcomputer 5302 sends a Low signal to the signal line CS to notify the camera microcomputer 5205 and the lens microcomputer 5111 that broadcast communication is to be started. Output is started (5411).

  Next, the adapter microcomputer 5302 stores the data to be transmitted in the transmission buffer 53033, and outputs the data to the signal line DATA according to the above-described communication format at the start of transmission (5412). On the other hand, the camera microcomputer 5205 and the lens microcomputer 5111 start low output to the signal line CS at the timing when the start bit ST input from the signal line DATA is detected (5413, 5414). At this point, since the adapter microcomputer 5302 has already started outputting Low to the signal line CS, the signal level transmitted to the signal line CS does not change.

  Next, after completing the output of the stop bit SP of the final data, the adapter microcomputer 5302 releases the Low output to the signal line CS (5415). On the other hand, the camera microcomputer 5205 and the lens microcomputer 5111 store the data in the reception buffers 52084 and 51124 each time the stop bit SP input from the signal line DATA is received, and when the Low is applied to the signal line CS, the reception buffer 52084 The data is extracted from 51124. Then, internal processing is performed on the data, and after the preparation for receiving the next data is completed, the Low output to the signal line CS is released (5416, 5417).

  FIG. 19B shows a case where the start of broadcast communication is notified from the lens microcomputer 5111 as an example. In this example, in response to broadcast communication from the camera microcomputer 5205 to the lens microcomputer 5111 and the adapter microcomputer 5302, broadcast communication is performed from the adapter microcomputer 5302 to the camera microcomputer 5205 and the lens microcomputer 5111.

  First, the lens microcomputer 5111 starts low output to the signal line CS in order to notify the camera microcomputer 5205 and the adapter microcomputer 5302 that broadcast communication is started (5421). Next, when detecting that the signal level of the signal line CS has become Low level, the camera microcomputer 5205 starts outputting Low to the signal line CS (5422). At this point, since the lens microcomputer 5111 has already started outputting Low to the signal line CS, the signal level propagated to the signal line CS does not change.

  Next, the camera microcomputer 5205 stores the data to be transmitted in the transmission buffer 52083, and outputs the data to the signal line DATA in accordance with the above-described communication format when transmission starts (5423). On the other hand, the adapter microcomputer 5302 starts low output to the signal line CS at the timing when the start bit ST input from the signal line DATA is detected (5424). At this point, since the camera microcomputer 5205 has already started outputting Low to the signal line CS, the signal level propagated to the signal line CS does not change.

  Next, after completing the output of the stop bit SP of the final data, the camera microcomputer 5205 releases the Low output to the signal line CS (5425). On the other hand, the lens microcomputer 5111 and the adapter microcomputer 5302 store the data in the receiving buffers 51124 and 53034 each time the stop bit SP input from the signal line DATA is received, and when the Low to the signal line CS is detected, the receiving buffer 51124 The data is extracted from 53034. Then, internal processing is performed on the data, and after the preparation for receiving the next data is completed, the Low output to the signal line CS is released (5426, 5427). As described above, the signal level of the signal line CS becomes Hi when all of the camera microcomputer 5205, the lens microcomputer 5111, and the adapter microcomputer 5302 cancel the Low output to the signal line CS. Therefore, the camera microcomputer 5205, the lens microcomputer 5111, and the adapter microcomputer 5302 confirm that the signal level of the signal line CS becomes Hi after releasing the Low output to the signal line CS, respectively. As a result, the camera microcomputer 5205, the lens microcomputer 5111, and the adapter microcomputer 5302 can each determine that the processing related to the current communication has been completed and the preparations for performing the next communication have been completed.

  Next, after confirming that the signal level of the signal line CS has returned to Hi, the adapter microcomputer 5302 sends a Low signal to the signal line CS to notify the camera microcomputer 5205 and the lens microcomputer 5111 that broadcast communication is to be started. Output is started (5431).

  Next, the adapter microcomputer 5302 stores the data to be transmitted in the transmission buffer 53033, and outputs the data to the signal line DATA according to the above-described communication format at the start of the transmission (5432). On the other hand, the camera microcomputer 5205 and the lens microcomputer 5111 start low output to the signal line CS at the timing when the start bit ST input from the signal line DATA is detected (5433, 5434). At this point, since the adapter microcomputer 5302 has already started outputting Low to the signal line CS, the signal level transmitted to the signal line CS does not change.

  Next, after completing the output of the stop bit SP of the final data, the adapter microcomputer 5302 releases the Low output to the signal line CS (5435). On the other hand, the camera microcomputer 5205 and the lens microcomputer 5111 store data in the reception buffers 52084 and 51124 each time they receive the stop bit SP input from the signal line DATA. Then, when a Low to the signal line CS is detected, the data is taken out from the reception buffer 52084, 51124. Further, the internal processing is performed on the data, and after the preparation for receiving the next data is completed, the Low output to the signal line CS is released (5436, 5437).

  In the example shown in FIG. 19B, when broadcast communication is started from the lens microcomputer 5111 and the adapter microcomputer 5302 as the communication slaves, the camera microcomputer 5205 as the communication master determines which of the lens microcomputer 5111 and the adapter microcomputer 5302 is connected to the signal line CS. Cannot be determined at 5421 as to whether or not. Therefore, the camera microcomputer 5205 needs to communicate with both the lens microcomputer 5111 and the adapter microcomputer 5302 to obtain information on whether or not broadcast communication has been started.

  Further, the timing when the camera microcomputer 5205 outputs Low to the signal line CS to start the broadcast communication and the timing when the lens microcomputer 5111 and the adapter microcomputer 5302 lower the signal line CS to Low to start the broadcast communication. May match. In this case, the camera microcomputer 5205 cannot detect that the lens microcomputer 5111 and the adapter microcomputer 5302 output Low on the signal line CS. For this reason, the camera microcomputer 5205 may notify the lens microcomputer 5111 and the adapter microcomputer 5302 of the communication slave of permission notification for permitting start of broadcast communication.

  As described above with reference to FIGS. 19A and 19B, the signal propagated using the signal line CS in the broadcast communication functions as a signal indicating that the broadcast communication has started and the communication process is being performed.

  19A and 19B, the example of the communication waveform of the broadcast communication in the first communication capable of the “one-to-many” communication has been described. However, the communication waveform of the broadcast communication in the first communication is another communication waveform. Is also good. For example, in FIG. 19A and FIG. 19B, the data transmitted in one broadcast communication is 1-byte data, but may be 2 bytes or 3 bytes. Also, the broadcast communication may be one-way limited communication from the camera microcomputer 5205 as the communication master to the lens microcomputer 5111 and the adapter microcomputer 5302 as the communication slave.

  Next, P2P communication performed between the camera body 5200, the interchangeable lens 5100, and the intermediate adapter 5300 using the signal line CS and the signal line DATA will be described with reference to signal waveforms shown in FIG. In P2P communication, a camera body 5200 as a communication master selects one of the communication partners from an interchangeable lens 5100 and an intermediate adapter 5300 as communication slaves. Then, “one-to-one” individual communication for transmitting and receiving data only between the camera body 5200 and the selected communication slave is performed.

  Here, the lens microcomputer 5111 is selected as a communication partner from the camera microcomputer 5205, and 2-byte data transmission is performed from the lens microcomputer 5111 to the camera microcomputer 5205 in response to 1-byte data transmission from the camera microcomputer 5205. Is shown. The number of transmission bytes need not be 51 bytes or 2 bytes as described above, and may be any number of bytes that allows both the transmitting side and the receiving side to communicate continuously. A method for switching between broadcast communication and P2P communication and a method for selecting a communication partner in P2P communication will be described later.

  First, the camera microcomputer 5205 serving as a communication master stores 51 bytes of data to be transmitted in the transmission buffer 52083, and outputs the data to the signal line DATA in accordance with the above-described communication format when the transmission starts (5501). After completing the output of the stop bit SP of the final data, the camera microcomputer 5205 starts outputting Low to the signal line CS (5502). After that, the camera microcomputer 5205 releases the Low output to the signal line CS after the preparation for receiving the next data is completed (5503).

  On the other hand, the lens microcomputer 5111 stores data in the reception buffer 51124 every time reception is performed up to the stop bit SP input from the signal line DATA. Then, when a low signal input from the signal line CS is detected, analysis of data stored in the reception buffer 51124 and internal processing on the data are performed. After that, when confirming that the signal level of the signal line CS has returned to Hi, the lens microcomputer 5111 stores two bytes of data to be transmitted in the transmission buffer 51123, and starts transmission and continuously transmits the signal line DATA according to the communication format described above. (5504). After completing the output of the stop bit SP of the second byte, the lens microcomputer 5111 starts outputting Low to the signal line CS (5505). After that, the lens microcomputer 5111 releases the Low output to the signal line CS after the preparation for receiving the next data is completed (5506).

  Note that the adapter microcomputer 5302 not selected as the communication partner of the P2P communication does not participate in the operation of the signal line CS and the signal line DATA at all.

  As described above with reference to FIG. 20, the signal propagated using the signal line CS in the P2P communication functions as a notification signal indicating the transmission end of the transmission side and a request for waiting for the next data transmission. Note that the communication waveform of the P2P communication shown in FIG. 20 is merely an example, and another communication waveform may be used. For example, the data to be transmitted may be one byte at a time or another number of bytes.

  Next, a method of switching between broadcast communication and P2P communication (communication mode switching) and a method of selecting a communication partner in P2P communication will be described with reference to signal waveforms shown in FIG. Selection of a communication partner in P2P communication is performed by broadcast communication. Here, a case where the following P2P communication is performed will be described as an example. First, the adapter microcomputer 5302 is selected (designated) by the camera microcomputer 5205 as a communication partner of the P2P communication. Then, P2P communication of 1-byte data transmission from the camera microcomputer 5205 to the adapter microcomputer 5302 and 1-byte data transmission from the adapter microcomputer 5302 to the camera microcomputer 5205 are performed. Next, the lens microcomputer 5111 is designated by the camera microcomputer 5205 as a communication partner of the P2P communication. Then, P2P communication of 2-byte data transmission from the camera microcomputer 5205 to the lens microcomputer 5111 and 3-byte data transmission from the lens microcomputer 5111 to the camera microcomputer 5205 are performed.

  First, the camera microcomputer 5205 serving as a communication master performs broadcast communication in the procedure described with reference to FIG. 19A (5601). What is notified by the broadcast communication is slave designation data that designates a communication partner with the camera microcomputer 5205 in the next P2P communication. The lens microcomputer 5111 and the adapter microcomputer 5302, which are communication slaves, determine from the slave designation data received by the broadcast communication whether or not themselves have been designated as communication partners of the P2P communication. By this broadcast communication, the camera microcomputer 5205 and the communication slave specified by the slave specification data are switched from the broadcast communication to the P2P communication (5602).

  Next, data is transmitted and received by P2P communication between the camera microcomputer 5205 and the adapter microcomputer 5302 designated as the communication partner according to the procedure described with reference to FIG. 20 (5603). Here, 1-byte data is transmitted from the camera microcomputer 5205 to the adapter microcomputer 5302, and then 1-byte data is transmitted from the adapter microcomputer 5302 to the camera microcomputer 5205.

  When the P2P communication between the camera microcomputer 5205 and the adapter microcomputer 5302 ends, the camera microcomputer 5205 can again specify a communication partner of the P2P communication by broadcast communication. Here, the camera microcomputer 5205 sets the lens microcomputer 5111 in the slave designation data to designate the lens microcomputer 5111 as the communication partner of the next P2P communication, and performs the broadcast communication in the procedure described with reference to FIG. 19A (5604). By this broadcast communication, the adapter microcomputer 5302 ends the P2P communication, while the lens microcomputer 5111 switches from the broadcast communication to the P2P communication (5605). If broadcast communication is not performed here, P2P communication between the camera microcomputer 5205 and the adapter microcomputer 5302 is continued.

  Next, the camera microcomputer 5205 and the lens microcomputer 5111 transmit and receive data in P2P communication according to the procedure described with reference to FIG. Here, the camera microcomputer 5205 transmits 2-byte data to the lens microcomputer 5111, and then the lens microcomputer 5111 transmits 3-byte data to the camera microcomputer 5205 (5606).

  As described above, in the first communication in which “one-to-many” communication is possible, a communication partner of P2P communication can be selected by broadcast communication, and switching between broadcast communication and P2P communication can be performed at the same time.

  Next, a process (communication control method) in the broadcast communication mode as the first communication mode performed between the camera body 5200, the interchangeable lens 5100, and the intermediate adapter 5300 will be described with reference to the flowcharts of FIGS. 22A and 22B. I do. Here, as an example, a case where broadcast communication is performed from the camera body 5200 to the interchangeable lens 5100 and the intermediate adapter 5300 will be described.

  FIG. 22A shows a broadcast communication transmission process in a broadcast communication mode in which data is transmitted from the camera microcomputer 5205 to the lens microcomputer 5111 and the adapter microcomputer 5302. This broadcast communication transmission processing is started when a requirement for starting broadcast communication occurs in the camera microcomputer 5205. For example, when requesting transmission of lens data or adapter data, or when the lens microcomputer 5111 and the adapter microcomputer 5302 output the signal line CS Low to request the start of broadcast communication. The camera microcomputer 5205 executes this processing according to a computer program.

  In the following description, S means a step. In step S5700, the camera microcomputer 5205 notifies the start of the broadcast communication to the lens microcomputer 5111 and the adapter microcomputer 5302 by turning on (connecting) the ground switch 52081 and setting the signal line CS to the low level. Upon receiving the broadcast communication start notification, the lens microcomputer 5111 and the adapter microcomputer 5302 start the broadcast communication reception process described with reference to FIG. 22B.

  Next, in step S5701, the camera microcomputer 5205 operates the input / output switch 52082 to connect the signal line DATA to the data output unit.

  Next, in step S5702, the camera microcomputer 5205 performs data transmission using the signal line DATA. When transmission of all data is completed, the process advances to step S5703. The number of bytes of data to be transmitted here may be any size as long as the recognition is the same among the camera microcomputer 5205, the lens microcomputer 5111, and the adapter microcomputer 5302, and the size can be transmitted and received at one time in the transmission / reception buffer of each microcomputer 5.

  In step S5703, the camera microcomputer 5205 determines whether the data transmitted in step S5702 is a bidirectional command including transmission from the lens microcomputer 5111 or the adapter microcomputer 5302. If the transmission data is not a bidirectional command, the camera microcomputer 5205 proceeds to S5704, and if it is a bidirectional command, proceeds to S5705.

  In step S5704, the camera microcomputer 5205 turns off (blocks) the ground switch 52081 to indicate that the communication processing has been completed, and releases the Low output to the signal line CS. Then, the process proceeds to S5715.

  In S5705, the camera microcomputer 5205 operates the input / output switch 52082 to connect the signal line DATA to the data input unit.

  Next, in step S5706, the camera microcomputer 5205 turns off (cuts off) the ground switch 52081 to release the Low output to the signal line CS in order to indicate that the communication processing has been completed.

  Next, in step S5707, the camera microcomputer 5205 waits until the lens microcomputer 5111 and the adapter microcomputer 5302 complete data reception, that is, until the signal line CS becomes Hi. When the signal line CS becomes Hi, the process proceeds to S5708.

  In step S5708, the camera microcomputer 5205 waits until the signal line CS goes low to wait for data transmission from the lens microcomputer 5111 or the adapter microcomputer 5302. When the signal line CS becomes Low, the process proceeds to S5709.

  In step S5709, the camera microcomputer 5205 permits data reception from the signal line DATA. Subsequently, in S5710, the camera microcomputer 5205 waits until a start bit of the signal line DATA is detected. If a start bit is detected, the flow advances to step S5711.

  In step S5711, the camera microcomputer 5205 turns on (connects) the grounding switch 52081 to indicate that communication processing is being performed, and starts low output to the signal line CS.

  Next, in step S5712, the camera microcomputer 5205 waits until all data is received. Upon completion of receiving all data, the process advances to step S5713. The number of bytes of data received here may be any size as long as the camera microcomputer 5205, the lens microcomputer 5111, and the adapter microcomputer 5302 have the same recognition, and can transmit and receive at one time in the transmission and reception buffer of each microcomputer.

  Next, in step S5713, the camera microcomputer 5205 prohibits data reception from the signal line DATA.

  In step S5714, the camera microcomputer 5205 turns off (blocks) the ground switch 52081 to indicate that the communication process has been completed, and releases the Low output to the signal line CS. Thereafter, the process proceeds to S5715.

  In S5715, the camera microcomputer 5205 waits until the lens microcomputer 5111 and the adapter microcomputer 5302 complete data reception, that is, until the signal line CS becomes Hi. When the signal line CS becomes Hi, the process proceeds to S5716.

  In step S5716, the camera microcomputer 5205 determines whether the lens microcomputer 5111 and the adapter microcomputer 5302 have designated a communication partner in P2P communication with the data transmitted in step S5702. If the communication partner has been specified, the camera microcomputer 5205 proceeds to S5717; otherwise, the camera microcomputer 5205 ends the broadcast communication transmission process while maintaining the broadcast communication mode.

  In S5717, the camera microcomputer 5205 shifts from the broadcast communication mode to the P2P communication mode, and ends the broadcast communication transmission processing.

  By executing the above processing, data transmission using broadcast communication from the camera body 5200 to the interchangeable lens 5100 and the intermediate adapter 5300 can be realized.

  FIG. 22B shows a broadcast communication reception process in which the lens microcomputer 5111 and the adapter microcomputer 5302 receive data from the camera microcomputer 5205. The lens microcomputer 5111 and the adapter microcomputer 5302 are not limited to the broadcast communication mode or the P2P communication mode. When the signal line CS goes low during communication standby, the lens microcomputer 5111 and the adapter microcomputer 5302 recognize broadcast start notification and start broadcast communication reception processing. The lens microcomputer 5111 and the adapter microcomputer 5302 execute this processing according to a computer program.

  In S5720, the lens microcomputer 5111 and the adapter microcomputer 5302 permit data reception from the signal line DATA.

  Next, in step S5721, the lens microcomputer 5111 and the adapter microcomputer 5302 determine whether a start bit of the signal line DATA has been received. If the start bit has not been received, the process advances to step S5722.

  In S5722, the lens microcomputer 5111 and the adapter microcomputer 5302 determine whether or not the signal line CS is Hi. If the signal line CS is Hi, the process proceeds to S5723 to end the reception process of the broadcast communication. The process returns to S5721 to continue waiting.

  In S5723, the lens microcomputer 5111 and the adapter microcomputer 5302 prohibit data reception from the signal line DATA, and ends the broadcast communication reception processing.

  In step S5724, the lens microcomputer 5111 and the adapter microcomputer 5302 shift to the broadcast communication mode when they are in the P2P communication mode.

  Next, in step S5725, the lens microcomputer 5111 and the adapter microcomputer 5302 turn on (connect) the ground switch 51121 and the ground switch 53031 to start low output to the signal line CS to indicate that communication processing is being performed.

  In S5726, the lens microcomputer 5111 and the adapter microcomputer 5302 stand by until all data is received. When the reception of all data is completed, the process proceeds to S5727. The number of bytes of the data received here may be any size as long as the recognition is the same among the camera microcomputer 5205, the lens microcomputer 5111, and the adapter microcomputer 5302, and the size can be transmitted and received at one time in the transmission / reception buffer of each microcomputer 5.

  In S5727, the lens microcomputer 5111 and the adapter microcomputer 5302 prohibit data reception from the signal line DATA.

  Next, in S5728, the lens microcomputer 5111 and the adapter microcomputer 5302 turn off (cut off) the ground switch 51121 and the ground switch 53031 to release the Low output to the signal line CS to indicate that the communication processing has been completed.

  Next, in step S5729, the lens microcomputer 5111 and the adapter microcomputer 5302 determine whether or not the data received in step S5725 is a bi-directional command indicating transmission from itself. If the received data is a bidirectional command, the lens microcomputer 5111 and the adapter microcomputer 5302 proceed to S5730, otherwise proceed to S5735.

  In S5730, the lens microcomputer 5111 and the adapter microcomputer 5302 wait until the other microcomputer 5 completes data reception, that is, until the signal line CS becomes Hi. When the signal line CS becomes Hi, the process proceeds to S5731.

  In step S5731, the lens microcomputer 5111 and the adapter microcomputer 5302 turn on (connect) the ground switch 51121 and the ground switch 53031 to set the signal line CS to Low level to notify the start of broadcast communication.

  Next, in S5732, the lens microcomputer 5111 and the adapter microcomputer 5302 operate the input / output switch 51122 and the input / output switch 53032 to connect the signal line DATA to the data output unit.

  Next, in step S5733, the lens microcomputer 5111 and the adapter microcomputer 5302 perform data transmission using the signal line DATA. When all data transmission is completed, the process advances to step S5734. The number of bytes of data to be transmitted here may be any size as long as the recognition is the same among the camera microcomputer 5205, the lens microcomputer 5111, and the adapter microcomputer 5302, and the size can be transmitted and received at one time in the transmission / reception buffer of each microcomputer 5.

  In step S5734, the lens microcomputer 5111 and the adapter microcomputer 5302 turn off (cut off) the ground switch 51121 and the ground switch 53031 to release the Low output to the signal line CS in order to indicate that the data transmission processing has been completed. .

  Next, in S5735, the lens microcomputer 5111 and the adapter microcomputer 5302 wait until the other microcomputer 5 completes data reception, that is, until the signal line CS becomes Hi. When the signal line CS becomes Hi, the process proceeds to S5736.

  In S5736, the lens microcomputer 5111 and the adapter microcomputer 5302 determine whether or not the data received in S5726 has been specified by the camera microcomputer 5205 as a communication partner of P2P communication. If the lens microcomputer 5111 and the adapter microcomputer 5302 have been specified as communication partners, the process advances to step S5737, and if not, the broadcast communication mode is maintained and the broadcast communication reception processing ends.

  In S5737, the lens microcomputer 5111 and the adapter microcomputer 5302 permit data reception from the signal line DATA.

  Next, in S5738, the lens microcomputer 5111 and the adapter microcomputer 5302 shift from the broadcast communication mode to the P2P communication mode and end the broadcast communication reception processing.

  By executing the above processing, data reception using broadcast communication from the camera body 5200 to the interchangeable lens 5100 and the intermediate adapter 5300 can be realized.

  Next, processing performed in the P2P communication mode, which is the second communication mode, between the camera body 5200, the interchangeable lens 5100, and the intermediate adapter 5300 will be described with reference to the flowcharts shown in FIGS. 23A and 23B. Here, as an example, a case where P2P communication is performed from the camera body 5200 as a communication master to the intermediate adapter 5300 as a communication slave will be described.

  FIG. 23A shows a P2P communication transmission process performed by the camera microcomputer 5205 serving as a communication master in the P2P communication mode. This P2P communication transmission processing is started when a requirement for starting P2P communication occurs in the camera microcomputer 5205. The camera microcomputer 5205 executes this processing according to a computer program.

  In S5800, the camera microcomputer 5205 operates the input / output switch 52082 to connect the signal line DATA to the data output unit.

  Next, in S5801, the camera microcomputer 5205 performs data transmission using the signal line DATA. When the transmission of all data is completed, the camera microcomputer 5205 proceeds to S5802. Here, the number of bytes of the data to be transmitted may be any size as long as the recognition between the camera microcomputer 5205 and the adapter microcomputer 5302 matches, and the size can be transmitted and received at one time in the transmission and reception buffer of each microcomputer 5. If the camera microcomputer 5205 can divide transmission data and transmit the data, the size may be any size that can be received at once by the reception buffer of the adapter microcomputer 5302.

  In step S5802, the camera microcomputer 5205 turns on (connects) the ground switch 52081, starts low output to the signal line CS, and notifies the adapter microcomputer 5302 that data transmission by P2P communication has been completed. Upon receiving the data transmission completion of the P2P communication, the adapter microcomputer 5302 starts the P2P communication reception processing described with reference to FIG. 23B.

  In step S5803, the camera microcomputer 5205 determines whether the data transmitted in step S5802 is a bidirectional command including data transmission from the adapter microcomputer 5302. If the transmission data is not a bidirectional command, the camera microcomputer 5205 proceeds to S5804, and if it is a bidirectional command, proceeds to S5805.

  In step S5804, the camera microcomputer 5205 turns off (cuts off) the ground switch 52081 to release the Low output to the signal line CS in order to detect that the adapter microcomputer 5302 has completed data reception. Then, the process proceeds to S5809.

  In S5805, the camera microcomputer 5205 operates the input / output switch 52082 to connect the signal line DATA to the data input unit.

  Next, in step S5806, the camera microcomputer 5205 turns off (cuts off) the ground switch 52081 and cancels the Low output to the signal line CS in order to detect that the data transmission from the adapter microcomputer 5302 has been completed.

  Next, in step S5807, the camera microcomputer 5205 waits until data transmission from the adapter microcomputer 5302 is completed, that is, until the signal line CS becomes low. When the signal line CS goes low, the camera microcomputer 5205 determines that the data transmission from the adapter microcomputer 5302 has ended, and proceeds to S5808. The number of bytes of data to be received may be any size as long as the recognition between the camera microcomputer 5205 and the adapter microcomputer 5302 matches, and the size can be transmitted and received at one time in the transmission and reception buffer of each microcomputer 5. If the adapter microcomputer 5302 can divide the transmission data and transmit it, the size may be any size that can be received at once by the reception buffer of the camera microcomputer 5205.

  In step S5808, the camera microcomputer 5205 analyzes the data received from the signal line DATA.

  Next, in step S5809, the camera microcomputer 5205 waits until the signal line CS becomes Hi. Then, when the signal line CS becomes Hi, the camera microcomputer 5205 indicates that the current P2P communication has been completed, and the process proceeds to S5810.

  In S5810, the camera microcomputer 5205 determines whether to start broadcast communication in the next communication. The camera microcomputer 5205 proceeds to S5811 when starting broadcast communication, and ends the P2P communication transmission process in the P2P communication mode when continuing P2P communication.

  In step S5811, the camera microcomputer 5205 shifts from the P2P communication mode to the broadcast communication mode, and ends the P2P communication transmission processing.

  By performing the above processing, data transmission / reception using P2P communication from the camera body 5200 as the communication master to the intermediate adapter 5300 can be realized.

  FIG. 23B shows a P2P communication reception process performed by the adapter microcomputer 5302 in P2P communication between the camera microcomputer 5205 and the adapter microcomputer 5302 which is a communication slave. The P2P communication reception processing is started when data of P2P communication is received by the adapter microcomputer 5302. Adapter microcomputer 5302 executes this processing according to a computer program.

  In S5820, adapter microcomputer 5302 analyzes data received from signal line DATA.

  Next, in S5821, the adapter microcomputer 5302 waits until the signal line CS becomes Hi, that is, the completion of the processing in S5804 or S5806. When the signal line CS becomes Hi, the adapter microcomputer 5302 proceeds to S5822.

  In S5822, adapter microcomputer 5302 determines whether or not the received data analyzed in S5820 is a bidirectional command including data transmission from adapter microcomputer 5302. If the received data is not a bidirectional command, the adapter microcomputer 5302 proceeds to S5823. If the received data is a bidirectional command, the adapter microcomputer 5302 proceeds to S5824.

  In step S5823, the adapter microcomputer 5302 turns on (connects) and turns off (blocks) the ground switch 53031 to notify the camera microcomputer 5205 that data reception has been completed, thereby starting low output to the signal line CS. . Then, the process proceeds to S5828.

  In S5824, the adapter microcomputer 5302 operates the input / output switch 53032 to connect the signal line DATA to the data output unit.

  Next, in S5825, the adapter microcomputer 5302 performs data transmission using the signal line DATA, and when transmission of all data is completed, the process proceeds to S5826. Here, the number of bytes of the data to be transmitted may be any size as long as the recognition between the camera microcomputer 5205 and the adapter microcomputer 5302 matches, and the size can be transmitted and received at one time in the transmission and reception buffer of each microcomputer 5. If the adapter microcomputer 5302 can divide the transmission data and transmit it, the size may be any size that can be received at once by the reception buffer of the camera microcomputer 5205.

  Next, in S5826, the adapter microcomputer 5302 turns on (connects) the ground switch 53031 to start low output to the signal line CS in order to notify the camera microcomputer 5205 that the P2P communication has been completed. As a result, the adapter microcomputer 5302 notifies the camera microcomputer 5205 of the completion of data transmission by P2P communication.

  Next, in S5827, the adapter microcomputer 5302 operates the input / output switch 53032 to connect the signal line DATA to the data input unit.

  Next, in S5828, the adapter microcomputer 5302 turns off (blocks) the ground switch 53031 to release the Low output to the signal line CS.

  Next, in S5829, the adapter microcomputer 5302 waits until the signal line CS becomes Hi in order to detect that the camera microcomputer 5205 has completed the P2P communication. When the signal line CS becomes Hi, the adapter microcomputer 5302 ends the P2P communication reception processing.

  By performing the above processing, data transmission / reception using P2P communication of the intermediate adapter 5300, which is a communication slave, can be realized.

  Referring to the flowchart of FIG. 24, camera body 5200, interchangeable lens 5100, and intermediate adapter 5300, whose release times are different from each other, perform the first communication at a higher or optimum communication speed while ensuring their compatibility. Of the communication for the activation will be described. Here, as an example, a communication process (camera main body activation process) performed by the camera main body 5200 with the intermediate adapter 5300 when the interchangeable lens 5100 is connected to the camera main body 5200 via one intermediate adapter 5300 will be described. I do. However, the communication slave may be the interchangeable lens 5100. This process is performed on all of the plurality of accessories connected to the camera body 5200 including the interchangeable lens capable of the first communication. The camera microcomputer 5205 performs the following processing according to a computer program.

  In step S5900, the camera microcomputer 5205 performs authentication communication via the camera first communication circuit 5241 for recognizing what accessories are attached and how many accessories are attached. When authentication of all attached accessories (here, the intermediate adapter 5300 and the interchangeable lens 5100) is completed, the process advances to step S5901. Note that the authentication communication is performed at a communication bit rate in accordance with a communication speed specified in advance. However, if an accessory whose communication bit rate at which communication can be performed at higher speed is determined by authentication is attached, the communication bit rate of the P2P communication mode, which is the second communication mode, may be changed for the accessory. . In addition, the authentication communication is performed within a range of a continuously transmittable data size (hereinafter, referred to as a second continuously transmittable data size) defined mutually in advance.

  In S5901, the camera microcomputer 5205 performs an initialization process that can be started using the authentication information acquired in S5900. The initial setting is, for example, a display of an attached state of the accessory on the display unit 206 and a setting of optical information to the signal processing circuit 5203. As an initial setting, optical information for the intermediate adapter 5300 may be obtained from the interchangeable lens 5100 by notifying the information of the intermediate adapter 5300 to the interchangeable lens 5100 using the second communication. As described above, by acquiring the information of the attached accessory in advance, the process using the information can be started early, and the activation of the camera body 5200 can be accelerated.

  Next, in S5902, the camera microcomputer 5205 receives the adapter transmittable size (accessory transmittable size) from the adapter microcomputer 5302 via the camera first communication circuit 5241. The adapter transmittable size is a data size (number of data or data amount) that can be continuously transmitted by the adapter microcomputer 5302. The adapter transmittable size is determined, for example, by the buffer size of the transmission buffer 53033. Also, the adapter transmittable size is transmitted and received within the range of the second continuously transmittable data size, similarly to the authentication communication.

  In step S5903, the camera microcomputer 5205 compares the adapter transmittable size with the camera receivable size, which is the data size that the adapter can receive continuously. If the camera receivable size is smaller than the adapter receivable size, the camera microcomputer 5205 sets the camera receivable size to the camera-adapter maximum reception size as a first continuously receivable data size described later in S5904. On the other hand, if the adapter transmittable size is smaller than the camera receivable size, in step S5905, the adapter transmittable size is set to the camera-adapter maximum receive size. If the adapter microcomputer 5302 can divide transmission data and transmit the data, the process may shift from S5903 to S5904.

  The camera receivable size is determined, for example, by the buffer size of the reception buffer 52084. Further, the camera-adapter maximum reception size is the maximum data size that the camera microcomputer 5205 can continuously receive from the adapter microcomputer 5302. Subsequent data sizes of the camera microcomputer 5205 from the adapter microcomputer 5302 are controlled with the camera-adapter maximum reception size as an upper limit.

  The camera microcomputer 5205 that has proceeded from S5904 and S5905 to S5906 receives the information of the memory map for each command from the adapter microcomputer 5302 via the camera first communication circuit 5241. By this processing, the camera microcomputer 5205 can recognize a command that the adapter microcomputer 5302 can support. Details of the memory map will be described later with reference to FIG.

  Next, in step S5907, the camera microcomputer 5205 receives the adapter individual information from the adapter microcomputer 5302 via the camera first communication circuit 5241. The adapter individual information is information indicating an optical member, a mounting function, and the like of the intermediate adapter 5300. Since the data amount of the adapter individual information is large, communication efficiency can be increased by communicating the adapter individual information after the camera-adapter maximum reception size is determined. Also, the adapter individual information is transmitted and received within the range of the second continuously transmittable data size, similarly to the authentication communication.

  Next, in step S5908, the camera microcomputer 5205 receives the adapter receivable size (accessory receivable size) from the adapter microcomputer 5302 via the camera first communication circuit 5241. The adapter receivable size is a data size that the adapter microcomputer 5302 can continuously receive. The adapter receivable size is determined, for example, by the buffer size of the reception buffer 53034. Also, the adapter receivable size is transmitted and received within the range of the second continuously transmittable data size, similarly to the authentication communication.

  Next, in step S5909, the camera microcomputer 5205 compares the adapter receivable size with the camera transmittable size, which is the data size that can be transmitted continuously by itself. If the camera transmittable size is smaller than the adapter receivable size, the camera microcomputer 5205 sets the camera transmittable size to a camera-adapter maximum transmit size as a first continuously transmittable data size described later in S5910. If the adapter receivable size is smaller than the camera transmittable size, in step S5911 the adapter receivable size is set to the camera-adapter maximum transmission size. If the camera microcomputer 5205 can divide transmission data and transmit the data, the process may shift from S5909 to S5911.

  The camera transmittable size is determined, for example, by the buffer size of the transmission buffer 52083. The camera-adapter maximum transmission size is the maximum data size that the camera microcomputer 5205 can continuously transmit to the adapter microcomputer 5302. Thereafter, the size of data transmitted from the camera microcomputer 5205 to the adapter microcomputer 5302 is controlled with this size as an upper limit.

  In step S5912, the camera microcomputer 5205 transmits the camera individual information to the adapter microcomputer 5302 via the camera first communication circuit 5241. The camera individual information is information such as functions mounted on the camera body 5100. Since the data amount of the camera individual information is large, communication efficiency can be improved by communicating the camera individual information after the camera-adapter maximum transmission size is determined. After S5912, the camera microcomputer 5205 ends the camera main body activation processing.

  The camera microcomputer 5205 sets the first continuously receivable data size and the first continuously transmittable data size described above for each accessory (interchangeable lens 5100 and intermediate adapter 5300). Then, the camera microcomputer 5205 communicates with each accessory at the first continuous receivable data size set for each accessory and at a data size up to the first continuous transmittable data size.

  By performing the above-described camera body activation processing when the camera body 5200 is activated, the optimum communication data size is set even in a combination of the camera body 5200 and accessories (interchangeable lens 5100 and intermediate adapter 5300) having different release times. be able to. Further, the camera main body 5200 can be started up at high speed.

  Next, referring to FIG. 25, in the second communication mode (P2P communication mode) of the first communication (“one-to-many” communication), the camera body 5200 and the accessory (the interchangeable lens 5100 and the intermediate adapter 5300) are previously set. An example of the format of the memory map (data arrangement information) to be defined will be described. The memory map is defined for each communication command. The memory map 51000 includes a plurality of data 51002, and an address 51001 is allocated to each data. The value 51003 of each data is updated at a fixed value or at an arbitrary timing. The memory map described here is a communication rule, and the data arrangement in the memory of each microcomputer may be different from the format of the present embodiment.

  The memory map is defined for each communication command. When the communication master receives the data of the memory map, the communication slave performs the P2P communication by designating the communication command and the address corresponding to the data to be received, and the communication slave takes out the specified data from the memory map and performs the P2P communication. Send to communication master. Similarly, when the communication master transmits the data of the memory map, the communication slave stores the specified data in the memory map by specifying a communication command and an address corresponding to the data to be transmitted. At this time, continuous data transmission and reception may be performed by designating the data size together with the address.

  Next, with reference to FIG. 26, an example of a communication command defined in advance between the camera body 5200 and the accessory in the second communication mode in the first communication will be described. Here, as an example, the camera microcomputer 5205 will be described as a communication master, and the adapter microcomputer 5302 will be described as a communication slave. Further, DC in the table of FIG. 26 is transmission data from the communication master to the communication slave, and data of 1 byte is continuously transmitted from 1 in order. DA is transmission data from the communication slave to the communication master, and data of 1 byte is continuously transmitted from 1 in order.

  First, a data reception command 51100, which is an example of a communication command (data transmission request) for a communication master to receive data from a communication slave using a memory map, will be described. The data DC transmitted from the camera microcomputer 5205 is a total of 5 bytes of data including the number of communication bytes, the command, the address of the memory map, the number N of received data (bytes), and the checksum in this order. The data DA transmitted from the adapter microcomputer 5302 is a total of (N + 3) bytes of data including the number of communication bytes, the command, N data from the data 51 to the data N, and the checksum in this order. DA commands and checksums are used to detect communication errors from the communication master to the communication slave. If an error is detected, the same communication is re-executed (retried) by the communication master.

The camera microcomputer 5205 sets the number N of received data so that DA does not exceed the above-described camera-adapter maximum reception size. That is,
Number of received data N ≦ Camera-adapter maximum received size-3
Set as Also, the camera-adapter maximum transmission size defined in advance between the camera body 5200 and the accessory needs to be 5 bytes or more, which is the DC transmission size.

  Next, a data transmission command 51101 will be described as an example of a communication command for causing the communication master to transmit data using the memory map by the communication master. The data DC transmitted from the camera microcomputer 5205 is a total of (N + 4) bytes of data including the number of communication bytes, the command, the address of the memory map, the N data from data 51 to data N, and the checksum in this order. . The data DA transmitted from the adapter microcomputer 5302 is 4-byte data including the number of communication bytes, the command, the number N of received data, and the checksum in this order. The DA command and the checksum are used to detect a communication error from the communication slave to the communication master. If an error is detected, the same communication is re-executed (retried) by the communication slave.

The camera microcomputer 5205 sets the number N of transmission data (bytes) so that DC does not exceed the camera-adapter maximum transmission size described above. That is,
Number of transmission data N ≦ Maximum transmission size of camera-adapter-4
Set as Also, the camera-adapter maximum reception size defined in advance between the camera body 5200 and the accessory needs to be 4 bytes or more, which is the DA transmission size.

  Next, a data transmission command 51102 which is an example of a communication command for causing the communication master to transmit data in order from the data of the head address using the memory map by the communication master will be described. Since this command is intended to transmit large-capacity data that needs to be transmitted from the data at the head address, this command is repeated until transmission of all data is completed, and is used, for example, for firmware upgrade of the adapter microcomputer 5302. The data DC transmitted from the camera microcomputer 5205 is a total of (N + 3) bytes of data including the number of communication bytes, the command, N data from data 51 to data N, and a checksum in this order. The data DA transmitted from the adapter microcomputer 5302 is 4-byte data including the number of communication bytes, the command, the number N of received data, and the checksum in this order. The DA command and the checksum are used to detect a communication error from the communication slave to the communication master. If an error is detected, the same communication is re-executed (retried) by the communication slave.

The camera microcomputer 5205 sets the transmission data number N so that the DC does not exceed the camera-adapter maximum transmission size described above. That is,
Number of transmission data N ≦ Maximum transmission size of camera-adapter-3
Set as Also, the camera-adapter maximum reception size defined in advance between the camera body 5200 and the accessory needs to be 4 bytes or more, which is the DA transmission size.

  Next, a communication process performed using a memory map in the second communication mode in the first communication will be described with reference to flowcharts shown in FIGS. 27A and 27B. Here, as an example, a communication process performed between the camera body 5200 as a communication master and the intermediate adapter 5300 as a communication slave will be described. However, the communication slave may be an interchangeable lens 5100.

  First, with reference to the flowchart of FIG. 27A, a process (memory map reception process) for the camera main body 5200 to receive continuous data on the memory map from the intermediate adapter 5300 will be described. The camera microcomputer 5205 performs data reception using the data reception command 51100 described above.

  In step S51200, the camera microcomputer 5205 sets a command (data transmission request) corresponding to data requested to be transmitted, a start address S_ADR of the memory map, and a total number of received data A_N.

Next, in S51201, the camera microcomputer 5205 sets the memory map address ADR and the number N of received data to be transmitted in the current communication according to the set start address S_ADR and the total number of received data A_N. For example,
Memory map address ADR = start address S_ADR
Number of received data N = Total number of received data A_N
Set as Thereafter, the number N of received data is limited so that DA does not exceed the camera-adapter maximum reception size described above. That is, if the number of received data N> camera-adapter maximum reception size−3,
Number of received data N = camera-adapter maximum received size-3
And set again. And
Start address S_ADR = Start address S_ADR + Number of received data N
Received data total number A_N = Received data total number A_N−Received data number N
And set again. Thereby, the data to be transmitted this time is determined, and at the same time, the remaining data number is reset to the total number of received data A_N, so that it is possible to determine whether there is data to be transmitted next time.

  Next, in S51202, the camera microcomputer 5205 stores the command set in S51200 and S5121, the memory map address ADR, and the number N of received data in the transmission buffer 52083 in accordance with the DC format of the data reception command 51100.

  Next, in S51203, the camera microcomputer 5205 transmits DC to the adapter microcomputer 5302 via the camera first communication circuit 5241. Further, the camera microcomputer 5205 receives DA from the adapter microcomputer 5302 via the camera first communication circuit 5241. Further, the camera microcomputer 5205 may divide and transmit the transmission data in a plurality of times by dividing and storing the transmission data in the transmission buffer 52083 and repeating steps S51202 and S51203 up to DC transmission.

Next, in S51204, the camera microcomputer 5205 takes out the reception data stored in the reception buffer 52084 and stores it in a predetermined memory. If the camera microcomputer 5205 detects a communication error such as a checksum error when extracting the received data,
Start address S_ADR = start address S_ADR-number of received data N
Received data total number A_N = Received data total number A_N + Received data number N
And set again. As a result, the start address S_ADR and the total number of received data A_N can be returned to values before communication, and communication retry control can be performed.

  Subsequently, in step S51205, the camera microcomputer 5205 determines whether or not reception of all data from the adapter microcomputer 5302 has been completed. If reception has been completed, the camera microcomputer 5205 terminates the present process. Otherwise, the process returns to step S5201. In this embodiment, since the remaining data number is set to the total number of received data A_N, if the total number of received data A_N is 1 or more, the camera microcomputer 5205 returns to S51201.

  Next, with reference to the flowchart of FIG. 27B, a process (memory map transmission process) for the camera body 5200 to transmit continuous data on the memory map from the intermediate adapter 5300 will be described. The camera microcomputer 5205 performs data transmission using the data transmission commands 51101 and 51102 described above.

  In S51210, the camera microcomputer 5205 sets the command (data reception request) corresponding to the data to be transmitted, the start address S_ADR of the memory map, and the total number of transmission data A_N. However, when data transmission is performed using the data transmission command 51102, it is not necessary to set the start address S_ADR.

Next, in S51211, the camera microcomputer 5205 sets the memory map address ADR and the number N of transmission data to be transmitted in this communication according to the set start address S_ADR and the total number A_N of transmission data. For example,
Memory map address ADR = start address S_ADR
Number of transmission data N = Total number of transmission data A_N
Set as After that, the camera microcomputer 5205 limits the number N of transmission data so that DA does not exceed the above-described camera-adapter maximum reception size. That is, when the number of transmission data N> the camera-adapter maximum transmission size−4,
Number of transmission data N = camera-adapter maximum reception size-4
And set again. And
Start address S_ADR = start address S_ADR + number of transmission data N
Total number of transmitted data A_N = Total number of transmitted data A_N−Number of transmitted data N
And set again. As a result, the data to be transmitted this time is determined, and at the same time, the remaining data number is reset to the total number of transmission data A_N, so that it is possible to determine whether there is data to be transmitted next time. However, when data is transmitted using the data transmission command 51102, it is not necessary to set the memory map address ADR and the start address S_ADR.

  Next, in step S5122, the camera microcomputer 5205 converts the command set in steps S51210 and S51211, continuous data including the memory map address ADR and the number N of transmission data, and a checksum into the transmission buffer 52083 according to the DC format of the data transmission commands 51101 and 51102. To be stored.

  Next, in step S51213, the camera microcomputer 5205 transmits DC to the adapter microcomputer 5302 via the camera first communication circuit 5241. Thereafter, the camera microcomputer 5205 receives DA from the adapter microcomputer 5302 via the camera first communication circuit 5241. Further, the camera microcomputer 5205 may divide and transmit the transmission data in a plurality of times by dividing the transmission data into the transmission buffer 52083 and storing the transmission data in the transmission buffer 52083, and repeating S51212 and S51213 up to DC transmission.

Next, in S51214, the camera microcomputer 5205 takes out the reception data stored in the reception buffer 52084 and stores it in a predetermined memory. If the camera microcomputer 5205 detects a communication error such as a checksum error when extracting the received data,
Start address S_ADR = start address S_ADR-number of transmission data N
Total number of transmitted data A_N = Total number of transmitted data A_N + Number of transmitted data N
And set again. As a result, the start address S_ADR and the total number of transmission data A_N can be returned to values before communication, and communication retry control can be performed.

  Next, in step S51215, the camera microcomputer 5205 determines whether or not transmission of all data to the adapter microcomputer 5302 has been completed. If the transmission has been completed, the camera microcomputer 5205 terminates this process. Otherwise, the process returns to step S51211. . In this embodiment, since the remaining data number is set to the total transmission data number A_N, if the total transmission data number A_N is 1 or more, the camera microcomputer 5205 returns to S51211.

  Next, the processing (intermediate adapter communication processing) performed when the intermediate adapter 5300 receives the P2P communication from the camera body 5200 will be described with reference to the flowchart shown in FIG. Adapter microcomputer 5302 executes this processing according to a computer program.

  In S51220, the adapter microcomputer 5302 takes out the reception data stored in the reception buffer 53034 and stores it in a predetermined memory.

  Next, in S51221, the adapter microcomputer 5302 analyzes which command has been received from the received data stored in the predetermined memory.

  Next, in S51222, the adapter microcomputer 5302 performs a process corresponding to the received command. For example, the received data is stored in a predetermined memory, the mounted function is operated, and information on the mounted function is stored in the predetermined memory.

  Next, in step S51223, the adapter microcomputer 5302 determines whether the received command is a data reception command from the camera microcomputer 5205. If a data reception command has been received, the process advances to step S51224; otherwise, the process advances to step S51225.

  In S51224, the adapter microcomputer 5302 stores the data in the transmission buffer 53033 according to the received data reception command. For example, of the memory map corresponding to the data reception command 51100, data is extracted from the memory map address indicated by the data reception command 51100 by the number of reception data indicated by the data reception command 51100. Then, adapter microcomputer 5302 stores the read data in transmission buffer 53033 according to the format of DA.

  On the other hand, in step S51225, the adapter microcomputer 5302 determines whether the received command is a data transmission command (51101 or 51102) from the camera microcomputer 5205. If a data transmission command has been received, the process advances to step S51226; otherwise, the process advances to step S51229.

  In S51226, adapter microcomputer 5302 stores the data in the memory map corresponding to the received data transmission command. That is, adapter microcomputer 5302 updates existing data with the received data. For example, when receiving the data transmission command 51101, the adapter microcomputer 5302 continuously stores the data received from the camera microcomputer 5205 from the address indicated in the data transmission command 51101 in the memory map. When the data transmission command 51102 is received for the first time, the adapter microcomputer 5302 receives the data transmission command 51102 from the head address of the memory map, otherwise, receives the data transmission command 51102 from the camera microcomputer 5205 from the address next to the address where the previous data was stored. The stored data is stored continuously.

  Next, in S51227, the adapter microcomputer 5302 stores data to be transmitted in response to the transmission buffer 53033 according to the format of the DA in the received data transmission command.

  On the other hand, in step S51229, the adapter microcomputer 5302 determines whether the received data transmission command is a command that requires a response to the camera microcomputer 5205. If so, the process advances to step S51227. Otherwise, the process ends.

  The adapter microcomputer 5302 that has proceeded from S51224 or S51227 to S51228 transmits the DA stored in the transmission buffer 53033 to the camera microcomputer 5205 via the adapter first communication circuit 5341. Then, the present process ends. The adapter microcomputer 5302 may divide and store the transmission data in the transmission buffer 53033 and repeat the steps S51224 or S51227 and S51228 until the transmission of the DA, thereby dividing and transmitting the transmission data a plurality of times. .

  By performing the above processing, communication with the intermediate adapter 5300 can be performed within a range in which the intermediate adapter 5300 can continuously communicate, so that communication can be performed at an optimal communication speed that matches the communication performance of the intermediate adapter 5300. .

  According to the present embodiment, “one-to-many” communication between the camera body 5200 and a plurality of accessories including the interchangeable lens 5100 and the intermediate adapter 5300 is performed while guaranteeing their compatibility even when their release dates are different from each other. Can be performed at a higher or optimal communication speed.

  A sixth embodiment of the present invention will be described. The sixth embodiment has the same configuration as that of the fifth embodiment, but when using a camera body and accessories whose release timings are different from each other, it is possible to communicate with an optimum amount of data while ensuring compatibility of commands, and This is an embodiment capable of controlling accessories. By receiving the memory map size as the memory map information when the camera body is activated, communication and control can be performed according to the expansion state of the memory map in the accessory.

  With reference to FIG. 29, an example of an extended format of a memory map defined in advance between the camera body 5200 and the accessory in the second communication mode (P2P communication mode) in the first communication (“one-to-many” communication) will be described. . The extended format of the memory map is defined for each communication command.

  The memory map 51300 has an extended format for the memory map 51000 described in the fifth embodiment, and includes a plurality of data 51302. An address 51301 is assigned to each of the plurality of data 51302. The value 51303 of each data is updated at a fixed value or at an arbitrary timing. The address 51301 is the same address as the memory map 51000 up to the address N-1, and the subsequent address N + M-1 is the extended address area.

  In S5906 of the flowchart shown in FIG. 24, the adapter microcomputer 5302 corresponding to the memory map 51000 transmits the memory map size N to the camera microcomputer 5205 as memory map information. On the other hand, the adapter microcomputer 5302 corresponding to the memory map 51300 transmits the memory map size N + M−1 as the memory map information to the camera microcomputer 5205.

  At this time, if the camera microcomputer 5205 corresponds to the memory map 51000, data communication is performed with any of the adapter microcomputers 5302 in an address area up to the address N-1. On the other hand, when the camera microcomputer 5205 supports the memory map 51300, data communication with the adapter microcomputer 5302 that transmits the memory map size N is performed in the address area up to the address N-1. . Further, data communication is performed with respect to the adapter microcomputer 5302 that transmits the memory map size N + M−1 in an address area up to the address N + M−1.

  By adopting such a configuration, each adapter microcomputer 5 can be controlled within a corresponding data range, so that communication and control can be performed according to the expansion status of the memory map of the accessory.

  The information transmitted to the camera microcomputer 5205 as the memory map information may be information associated with the memory map size, such as a memory map version, instead of the memory map size itself. That is, any information on the memory map size may be used.

According to the present embodiment, the “one-to-many” communication between the camera body and a plurality of accessories including the interchangeable lens and the intermediate adapter can be performed in an optimal manner while guaranteeing their compatibility even when their release dates are different from each other. Communication based on the amount of data and optimal accessory control can be performed.
(Other Examples)
The present invention supplies a program for realizing one or more functions of the above-described embodiments to a system or an apparatus via a network or a storage medium, and one or more processors in a computer of the system or the apparatus read and execute the program. This processing can be realized. Further, it can also be realized by a circuit (for example, an ASIC) that realizes one or more functions.

  Each of the embodiments described above is only a typical example, and various modifications and changes can be made to each embodiment when the present invention is implemented.

100 Interchangeable lens (accessory device)
111 Lens microcomputer 141, 241, 341 First communication circuit 142, 242, 342 Second communication circuit 200 Camera body (imaging device)
205 Camera microcomputer 300 Intermediate adapter (accessory device)
302 Adapter microcomputer

Claims (39)

An imaging device to which an accessory device is detachably attached,
A camera communication unit that provides a communication path with the accessory device;
A camera control unit that communicates with the accessory device via the camera communication unit,
The camera control unit includes:
From the accessory device, an accessory transmittable size indicating a data size that the accessory device can continuously transmit, and an accessory receivable size indicating a data size that the accessory device can continuously receive,
The camera control unit sets the first continuously receivable data size based on the continuously receivable data size and the accessory transmittable size,
The camera control unit sets a first continuously transmittable data size based on the continuously transmittable data size and the accessory receivable size,
An image capturing apparatus, wherein communication with the accessory device is performed with the first continuous receivable data size and a data size having the first continuous transmittable data size as an upper limit. The camera control unit includes:
The camera control unit sets the smaller of the continuously receivable data size and the accessory transmittable size as the first continuously receivable data size,
2. The imaging apparatus according to claim 1, wherein the camera control unit sets a smaller one of the data size that can be continuously transmitted and the accessory receivable size as the first continuously transmittable data size. 3. apparatus.   The camera control unit sets the first continuously receivable data size and the first continuously transmittable data size for each accessory device when a plurality of accessory devices are mounted on the imaging device. The imaging device according to claim 1, wherein: The accessory device has accessory data that can be transmitted and received to and from the camera control unit,
The imaging device according to claim 1, wherein the camera control unit receives data arrangement information of the accessory data from the accessory device.   The camera control unit, according to the data arrangement information of the accessory data and the first continuously receivable data size, continuously receives the accessory data from the accessory device in a range of the continuously receivable data size. The imaging device according to claim 4, wherein:   The camera control unit, according to the data arrangement information of the accessory data and the first continuously transmittable data size, continuously transmits the accessory data to the accessory device within a range of the continuously transmittable data size. The imaging device according to claim 4 or 5, wherein   7. The camera control unit according to claim 1, wherein when an error in communication with the accessory device is detected, the camera control unit re-executes the communication with the accessory device. 8. Imaging device.   Before the first continuously receivable data size is set, the camera control unit may control the accessory according to a second continuously receivable data size set between the camera control unit and the accessory device. The imaging device according to claim 1, wherein the imaging device receives transmission data from the device.   Before the first continuously transmittable data size is set, the camera control unit may control the accessory according to a second continuously transmittable data size set between the camera control unit and the accessory device. The imaging device according to claim 1, wherein data is transmitted to the device. An accessory device detachably attached to the imaging device,
An accessory communication unit that provides a communication path between the image pickup device and
An accessory control unit that communicates with the imaging device via the accessory communication unit,
The accessory control unit captures an accessory transmittable size indicating a data size that can be continuously transmitted by the accessory control unit and an accessory receivable size indicating a data size that can be continuously received by the accessory control unit. An accessory device for transmitting to the device. The accessory control unit has accessory data that can be transmitted to and received from the imaging device,
The accessory device according to claim 10, wherein data arrangement information of the accessory data is transmitted to the imaging device.   The accessory device according to claim 10, wherein the accessory control unit continuously transmits the accessory data to the imaging device in response to a data transmission request from the imaging device.   The said accessory control part receives the said accessory data continuously according to the data reception request | requirement from the said imaging device, and updates the said existing accessory data with the received said accessory data, The Claims 11 or 12 characterized by the above-mentioned. An accessory device according to any one of the preceding claims.   The accessory device according to any one of claims 10 to 11, wherein, when the accessory control unit detects an error with respect to communication from the imaging device, the accessory control unit notifies the imaging device of the error. A communication control method of an imaging device in which an accessory device is detachably mounted and communicably mounted,
From the accessory device, receiving an accessory transmittable size indicating a data size that the accessory device can continuously transmit, and an accessory receivable size indicating a data size that the accessory device can continuously receive,
Setting the first continuous receivable data size based on the data size receivable by the imaging device and the accessory transmittable size;
Setting the first continuously transmittable data size based on the data size that can be continuously transmitted by the imaging device and the accessory receivable size;
Performing communication with the accessory device with the first continuously receivable data size and a data size having the first continuously receivable data size as an upper limit. A communication control method of an accessory device that is detachably attached to and communicable with an imaging device,
Transmitting an accessory transmittable size indicating a data size that can be continuously transmitted by the accessory device to the imaging device;
Transmitting an accessory receivable size indicating a data size that can be continuously received by the accessory device to the imaging device.   A computer program for causing a computer of an imaging device to execute a process according to the communication control method according to claim 15.   17. A computer program for causing a computer of an accessory device connectable to an imaging device to execute processing according to the communication control method according to claim 16. An imaging device to which an accessory device can be attached,
A camera control unit that communicates with the accessory device,
The camera control unit receives first information regarding a data size that the accessory device can receive,
The imaging device, wherein the camera control unit sets a data size to be transmitted to the accessory device based on the first information, and communicates with the accessory device based on the setting.   20. The imaging device according to claim 19, wherein the camera control unit transmits individual information of the imaging device based on the setting.   20. The imaging apparatus according to claim 19, wherein the camera control unit transmits data having a data size equal to or smaller than a data size based on the first information to the accessory. The camera control unit receives, from the accessory device, second information regarding a data size that can be transmitted by the accessory device,
20. The imaging apparatus according to claim 19, wherein the camera control unit sets a data size to be received from the accessory device based on the second information, and communicates with the accessory device based on the setting. apparatus.   23. The imaging apparatus according to claim 22, wherein the camera control unit requests the accessory for data whose data size is equal to or smaller than a data size based on the second information.   20. The imaging apparatus according to claim 19, wherein the camera control unit receives the individual information of the accessory device after receiving the second information. 20. The imaging apparatus according to claim 19, wherein the camera control unit receives information about a memory map corresponding to a command after receiving the second information.   20. The imaging apparatus according to claim 19, wherein the camera control unit communicates with the accessory device via a camera communication unit.   20. The imaging device according to claim 19, wherein a lens device is mounted on an opposite side of the imaging device via the accessory device. An accessory device that can be attached to the imaging device,
An accessory control unit that communicates with the imaging device,
The accessory device, wherein the accessory control unit transmits first information on a data size receivable by the accessory device and second information on a data size receivable by the accessory device.   The accessory device according to claim 28, wherein the accessory control unit receives the individual information of the imaging device after transmitting the first information.   The accessory device according to claim 28, wherein the accessory control unit transmits the individual information of the accessory after transmitting the second information.   29. The accessory device according to claim 28, wherein the accessory control unit transmits information on a memory map corresponding to a command after transmitting the second information.   The accessory device according to claim 28, wherein the accessory control unit transmits data whose data size is equal to or smaller than a data size based on the first information.   The accessory device according to claim 28, wherein the accessory control unit transmits data whose data size is equal to or smaller than a data size based on the second information. An accessory device according to claim 40,
The accessory device according to claim 28, wherein the accessory control unit communicates with the imaging device via an accessory communication unit.   The accessory device according to claim 28, wherein a lens device is attached to the accessory device on a side opposite to the imaging device. A communication control method of an imaging device to which an accessory device can be attached,
Receiving first information about a data size that the accessory device can receive;
Setting a data size to be transmitted to the accessory device based on the first information, and communicating with the accessory device based on the setting. A communication control method for an accessory device that can be attached to an imaging device,
Transmitting first information about a data size that the accessory device can receive;
Transmitting second information about a data size that can be transmitted by the accessory device.   A computer program for causing a computer of an imaging device to execute processing according to the communication control method according to claim 36.   A computer program for causing a computer of an accessory device connectable to an imaging device to execute processing according to the communication control method according to claim 37.