JP2005085220A - Interface device and image forming apparatus using it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an executable means that is free from complicated processings, without increase in processing run time, even when rewriting a control program of a printer engine. <P>SOLUTION: Normally, a communication method between a video controller and engine is conducted by adding parity bits for processing errors. When transmitting and receiving mass data, such as rewriting a flash memory, the transmission and reception of data is conducted by the maximum bit width, without adding parity bits, and the parity data with a unified unit are transmitted separately. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an interface device that connects a control unit such as a video controller and a controlled unit such as an engine controller in a printer, a printing apparatus using the interface device, and an interface control method.

  A conventional interface apparatus will be described by taking a printing apparatus as an example. A conventional printing apparatus includes a video controller that converts image information into bitmap data and a printer engine that forms an image based on the pixel data and transfers and fixes the image on a recording medium. An interface between the video controller and the printer engine is called a video I / F, and an example is shown below.

  FIG. 4 is a diagram showing a list of video I / F signals. In FIG. 4, “output” indicates an output from the engine to the video controller, and “input” indicates an input from the video controller to the engine. The engine includes an engine controller that controls the engine. Signal exchange with the video controller and engine control are performed by the engine controller.

  The / BD signal is a horizontal synchronizing signal in the main scanning direction of the printer engine, and the video controller sends video data / VDO signal for one main scanning line in synchronization with the falling of the / BD signal.

  The / RDY signal is a signal indicating that the printing operation is enabled by the printer engine in response to a print start command (/ PRNT signal is true) from the video controller. As a condition for the / RDY signal to be true, the temperature of the heating roller in the fixing unit is appropriate (temperature sufficient for fixing the toner image on the paper), the recording paper is not in a jammed state, and the polygon mirror is at a predetermined rotational speed. There is a normal rotation, the / BD signal is normally output in a predetermined cycle, and the like.

  The / TOP signal is a print synchronization signal in the sub-scanning direction in the printer engine, and the video controller sets an image writing position in the sub-scanning direction in synchronization with the falling of the / TOP signal.

  In this example, the time from when the leading edge of the recording paper is detected by the paper feed sensor to the time when the recording paper reaches the transfer roller, and the latent image formed on the photosensitive member by the laser light are rotated by the photosensitive drum. Thus, the paper feed sensor is arranged so that the time until it reaches the transfer roller becomes equal. For this reason, when the engine controller detects that the paper feed sensor signal (PFSNS) from the paper feed sensor has become true, it immediately sets the / TOP signal to true for 1 second.

  The / STS signal is 16-bit serial information transmitted from the engine controller to the video controller, and this signal is called a status.

  The / PRNT signal is a signal used by the video controller to instruct the printer engine to start a printing operation. However, in the case of continuous printing, this means continuation of the printing operation.

  The / CPRDY signal is a signal indicating that power is supplied to the video controller, initialization of the video controller is completed, and command status communication with the printer controller becomes possible.

  The / VDO signal indicates an image signal to be printed by the printer engine. This image signal is converted from image code data received by the video controller from the host computer, converted into dot data, and transmitted.

  The / CMD signal is 16-bit serial information transmitted from the video controller to the engine controller, and is called a command.

  The / SCLK signal is a serial data synchronization clock when the / CMD signal and the / STS signal are transmitted.

  Here, the configuration of commands sent from the video controller to the engine controller and status signals sent from the engine controller to the video controller, which are transmitted and received by serial communication, will be described.

  As described above, the command and status information are 16-bit serial signals. FIG. 5 shows the data format of the command and status information. For 16-bit data, MSB is defined as the most significant bit of transmission / reception data, the 15th bit is defined as the least significant bit of transmission / reception data, and LSB is defined as an odd parity bit.

  In the data format described above, when 1-word command information is supplied from the video controller to the engine controller in synchronization with the / SCLK signal, the engine controller returns a 1-word status to the video controller. This command includes a status request command for checking the status (state) of the printer engine and an execution command for instructing the printer engine to perform some operation.

  The / RESET signal is a signal for requesting initialization of the printer from the video controller to the engine controller. When this signal is at a LOW level for a predetermined time or more, the engine controller initializes the printer.

Further, it is described that printer engine control program data is transmitted from a video controller in order to upgrade the printer engine program (see, for example, Patent Document 1).
JP 2002-297389 A

  As described above, the 16-bit serial data which is the command and status information on the interface between the video controller and the printer engine has the MSB as the most significant bit of the transmission / reception data and the 15th bit as the least significant bit of the transmission / reception data. Are defined as odd parity bits. Here, when the printer engine control program data is transmitted from the video controller and the printer engine control program is rewritten, a large amount of data transmission is required. Since the control program data is usually handled in units of 16 bits, when data transmission / reception is performed in the data transmission / reception format in which only 15 bits are valid as described above, the control program code data is irregularly converted by 15 bits. Data transmission, or in order to simplify the conversion process, it is necessary to perform a process of either 8-bit unit conversion and transmission, which complicates the data processing and increases the data processing execution time. In addition, an increase in the amount of control program code for performing the conversion processing occurs, which causes an increase in the cost of the apparatus.

  SUMMARY OF THE INVENTION In view of the above problems, an object of the present invention is to propose means capable of executing a printer engine control program rewriting without complicating the processing and increasing the processing execution time. .

  In order to achieve the above object, the present invention has the following configuration.

  That is, an interface device for connecting a control side and a controlled side, a synchronization signal transmitting means for transmitting a synchronization signal from the control side between the control side and the controlled side, and the synchronization signal Serial data transmission / reception means for transmitting / receiving a data signal synchronized with the control side, the control side includes instruction means for instructing the controlled side to perform predetermined processing, and the controlled side is A process execution unit configured to execute the predetermined process, wherein the controlled side includes a rewritable memory, and the control program code data is stored in the rewritable memory; Means for transmitting the control program code data of the controlled side from the control side to the controlled side and rewriting the control program code data. The serial transmission / reception data format when the control program code rewriting is executed by the control program code rewriting means includes the code data rewriting means, and the transmission / reception data other than the case of executing the control program code rewriting is the data format An interface device comprising means for transmitting and receiving data by different means.

  According to a second aspect of the present invention, in the interface device configured as described above, the serial transmission / reception data has 16 bits as one data unit, and when rewriting the control program code, all 16 bits are used. An interface comprising: means for processing as transmission / reception data in a format in which a 1-bit parity bit is added to 15-bit data, except when the data area is defined and data control program code is rewritten Device.

  According to a third aspect of the present invention, in the interface device having the above-described configuration, the serial transmission / reception data has 16 bits as one data unit, and when the control program code is rewritten, all 16 bits are used. Means for defining a data area, and transmitting / receiving one piece of data for confirming the consistency of a plurality of transmitted / received data at the time of transmitting / receiving a plurality of predetermined data, and performing a consistency confirmation process for the transmitted / received data; It is an interface device characterized by comprising.

  According to a fourth aspect of the present invention, in the interface device configured as described above, when the control program code is rewritten, the transmission / reception data defining all 16 bits as a data area is the control program on the controlled side. An interface device characterized by code address information and control program code data.

  According to a fifth aspect of the present invention, the interface device configured as described above connects a video controller section that generates an image signal and an engine section that prints out the image signal generated by the video controller section. An image forming apparatus characterized by the above.

  As described above, if the present invention is organized and summarized, it can be integrated into the following configurations.

(1) An interface device for connecting a control side and a controlled side,
Between the control side and the controlled side, there is a synchronization signal transmission means for transmitting a synchronization signal from the control side, and a serial data transmission / reception means for transmitting and receiving a data signal synchronized with the synchronization signal,
The control side includes instruction means for instructing the controlled side to perform predetermined processing,
The controlled side includes processing execution means for executing the predetermined processing from the controlling side,
The controlled side has a rewritable memory, and has a configuration for storing control program code data in the rewritable memory,
A control program code data rewriting means for rewriting the control program code data by transmitting the control program code data of the controlled side from the control side to the controlled side by the serial data transmitting and receiving means;
The serial transmission / reception data format when the control program code data rewrite is executed by the control program code data rewrite means is different from the transmission / reception data except when the control program code data rewrite is executed by means of a data format different from that of the transmission / reception data. An interface device comprising means for performing transmission / reception.

  (2) In the interface device having the above-described configuration, the serial transmission / reception data format has 16 bits as one data unit, and when rewriting the control program code, all 16 bits are defined as a data area, and the control program The interface apparatus according to (1), further comprising means for processing as transmission / reception data in a format in which 1-bit parity bit is added to 15-bit data, except when code rewriting is performed.

  (3) In the interface device having the above-described configuration, the serial transmission / reception data has 16 bits as one data unit, and when rewriting the control program code, all 16 bits are defined as a data area and determined in advance. And (1) transmitting / receiving one piece of data for confirming the consistency of the plurality of transmitted / received data at the time of transmitting / receiving the plurality of data, and performing a process for confirming the consistency of the transmitted / received data. ) The interface device described.

  (4) In the interface device having the above configuration, when rewriting the control program code, the transmission / reception data defining all 16 bits as the data area includes address information and control program code data of the control program code on the controlled side The interface device according to (1), characterized in that:

  (5) An image forming apparatus comprising a video controller section that generates an image signal and an engine section that prints and outputs the image signal generated by the video controller section by the interface apparatus having the above-described configuration.

  As described above, the interface apparatus of the present invention, the printing apparatus using the interface apparatus, and the interface control method transfer control program code data from the control side to the controlled side, and rewrite the control program code on the controlled side. Even in such a case, it is possible to realize a means that can be executed without complicating the processing related to transmission / reception of the control program code data and without increasing the processing execution time.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is a block diagram illustrating the configuration of a printing apparatus according to the first embodiment of the present invention.

  In FIG. 1, the printing apparatus includes a controller unit 26 and an engine unit 25. In the controller unit 26, the CPU 16 receives image information from a host computer or the like via the interface 17 with an external device by executing a control program stored in the ROM 19. The received image information is input to the image processing unit 20. The image processing unit 20 stores the code data in the RAM 21 and analyzes the image information. The RAM 18 is used as a register. The ROM 22 stores font data corresponding to the value of the image information. The image processing unit 20 reads the corresponding font data from the ROM 22, converts the received image information into video data consisting of all dots, Store in the memory 23. When one page of video data is stored in the frame memory 23, the CPU 16 sends a print command to the engine unit 25 via the video interface 24 and is synchronized with the main / sub-scan synchronization signal from the engine unit 25. The video data stored in the frame memory 23 is sent to the engine unit 25. The engine unit 25 is controlled by an engine controller 25 a that is controlled by the CPU 30.

  FIG. 2 is a cross-sectional view showing an example of the engine unit 25 shown in FIG. 1, and the same components as those in FIG. In FIG. 2, a laser beam printer is shown as the printing apparatus main body 1 in the present embodiment. The optical unit 3 modulates the laser beam with the video data sent through the video interface 24, and scans the photosensitive drum 2 with the rotating polygon mirror. The folding mirror 4 reflects the laser light emitted from the optical unit 3. The charger 5 uniformly charges the photosensitive drum 2. The developing device 6 develops the electrostatic image on the photosensitive drum 2 into a toner image. The transfer machine 7 transfers the toner image on the photosensitive drum 2 to a recording sheet. The cleaner 8 collects the toner remaining on the photosensitive drum 2 after the transfer. The upper paper feed roller 10a feeds the paper stored in the upper cassette 9a. The lower feed roller 10b feeds the paper stored in the lower cassette 9b. The paper feeding / conveying roller 11 conveys the fed paper to the transfer position. The TOP sensor 12 detects the presence or absence of a fed sheet. The fixing device 13 heats and presses the toner image transferred onto the paper to fix it on the paper. The paper discharge sensor 14 detects the presence or absence of paper discharged from the fixing device 13. The arrangement tray 15 receives the recording paper to be discharged.

  FIG. 3 is a block diagram showing an interface between the video controller 26 and the engine controller 25a in the printing apparatus of this embodiment. FIG. 4 is a diagram showing a list of signals of the video interface 24.

  As shown in FIG. 3, in the engine controller 25a, the CPU 30 for controlling the printing device engine unit as described above, the RAM 31 as a memory for operating the CPU 30, and a control program code for performing engine control are written. The video interface 24 and other control loads are controlled around the flash ROM 32. Here, in the flash ROM 32 in which the control program code is written, the control program code is changed when the control of the printing apparatus is changed.

  A procedure for rewriting the control program code stored in the flash memory of the engine controller 25a through the interface between the video controller 26 and the engine controller 25a shown in FIGS. 3 and 4 in the configuration described above will be described. .

  FIG. 7 is a flowchart showing a procedure for rewriting the control program code stored in the flash memory 32 of the engine controller 25a in the configuration described above.

  When there is an instruction to rewrite the control program of the engine controller 25a from a host computer or an operation panel (not shown) connected to the video controller 26, the video controller 26 first sends the engine controller 25a to the control program code rewriting mode. It is designated that there is (S1001).

  As the next step, the actual start address for writing the control program code is designated from the video controller 26 to the engine controller 25a (S1002).

  As the next step, the control program code data transmitted from the host computer or the like via the external interface is designated from the video controller 26 to the engine controller 25a (S1003). The control program code data specified from the video controller 26 to the engine controller 25a does not specify one address for one write control program code data, but starts with the address specified in step S1002. As described above, a predetermined number of pieces of data are transmitted. Accordingly, it is determined whether or not a predetermined number of pieces of data have been transmitted (S1004). If the determination result indicates that a predetermined number of pieces of data have not been transmitted, the process returns to step S1003 to transmit control program code data. Thereafter, a predetermined number of pieces of data are determined. Until it is sent. If it is determined in step S1004 that a predetermined number of pieces of data have been transmitted, the transmission of the control program code data is completed.

  FIG. 8 is a timing chart showing the above-described processing flow as time-series data transmission / reception. As shown in FIG. 8, the transmission / reception of data from the video controller 26 to the engine controller 25a shown in FIG. 7 is configured such that the status is returned from the engine controller 25a corresponding to the transmission data from the video controller 26. Yes.

  FIG. 6 shows a data format transmitted from the video controller 26 to the engine controller 25a. The data format used at the time of rewriting the control program code shown in FIG. 6 is different from the format of FIG. 5 shown in the conventional example, and the parity bits added in FIG. It is defined as code data. By adopting this data format, even when a large amount of control program code data is sent and received, the control program code data is irregularly converted by 15 bits and transmitted, or converted into 8-bit units to simplify the conversion process. Thus, it is not necessary to perform any processing for transmission, and the processing in the video controller 26 and the engine controller 25a is simplified.

  The engine controller 25a that has received the predetermined control program code data writes the control program code data transmitted from the video controller 26 to the flash memory.

  Since the configuration of the printing apparatus is the same as that of the first embodiment, the description thereof is omitted.

  FIG. 9 is a flowchart showing a second procedure in the case where the control program code stored in the flash memory of the engine controller 25a is rewritten in the configuration described above.

  When there is an instruction to rewrite the control program of the engine controller 25a from a host computer or an operation panel (not shown) connected to the video controller 26, the video controller 26 first sends the engine controller 25a to the control program code rewriting mode. It is specified that there is (S1101).

  As the next step, the actual start address for writing the control program code is designated from the video controller 26 to the engine controller 25a (S1102).

  As the next step, control program code data transmitted from the host computer or the like is designated from the video controller 26 to the engine controller 25a (S1103). The control program code data specified from the video controller 26 to the engine controller 25a does not specify one address for one write control program code data, but starts with the address specified in step S1102. As described above, a predetermined number of pieces of data are transmitted. Therefore, it is determined whether or not a predetermined number of pieces of data have been transmitted (S1104). If the determination result indicates that the predetermined number of data is not transmitted, the process returns to step S1103 to transmit the control program code data, and thereafter the predetermined number of data is determined. Until it is sent. If it is determined in step S1104 that a predetermined number of pieces of data have been transmitted, the transmission of the control program code data is completed.

  Thereafter, the video controller 26 calculates odd parity for each bit position of the control program code data transferred from the video controller 26 to the engine controller 25a (S1105).

  The odd parity calculated above is transmitted from the video controller 26 to the engine controller 25a (S1106). FIG. 10 shows the data format of the odd parity for each bit transmitted at this time. The engine controller 25a confirms the consistency of the control program code data transmitted from the video controller 26 by the transmitted odd parity data.

  FIG. 11 is a timing chart showing the above-described processing flow as time-series data transmission / reception. As shown in FIG. 11, after transmitting the control program code data from the video controller 26 to the engine controller 25a, the odd parity data is finally transmitted.

  The engine controller 25a that has received the predetermined control program code data writes the control program code data transmitted from the video controller 26 to the flash memory.

  Note that the present invention can be applied to a system (for example, a copier, a facsimile machine, etc.) consisting of a single device even when applied to a system composed of a plurality of devices (for example, a host computer, interface device, reader, printer, etc.). You may apply.

Block diagram of printing apparatus of first and second embodiments The figure which shows the structure of the printing apparatus of 1st and 2nd embodiment. The block diagram which shows the interface of the video controller 26 and the engine controller 25a in the printing apparatus of 1st and 2nd embodiment. The figure which shows the list of the interface signals of the video controller 26 and the engine controller 25a in the printing apparatus of 1st and 2nd embodiment. The figure which shows the data format transmitted / received between the video controller 26 and the engine controller 25a in the printing apparatus of 1st and 2nd embodiment other than the time of the control program code data writing mode. The figure which shows the data format transmitted / received between the video controller 26 and the engine controller 25a at the time of the control program code data writing mode in the printing apparatus of 1st and 2nd embodiment. The flowchart which shows the outline | summary of the control procedure by the video controller 26 and engine controller 25a in 1st Embodiment. Time chart showing an outline of a communication control procedure by the video controller 26 and the engine controller 25a in the first embodiment The flowchart which shows the outline | summary of the control procedure by the video controller 26 and engine controller 25a in 2nd Embodiment. The figure which shows the odd parity data format transmitted / received between the video controller 26 and the engine controller 25a at the time of the control program code data writing mode in the printing apparatus of 2nd Embodiment. Time chart showing an outline of a communication control procedure by the video controller 26 and the engine controller 25a in the second embodiment

Explanation of symbols

1 Printing device 2 Photosensitive drum (latent image carrier)
3 Optical unit 4 Folding mirror 5 Charging machine 6 Developing machine 7 Transfer machine 8 Cleaner 9a Upper cassette 9b Lower cassette 10a Upper paper feed roller 10b Lower paper feed roller 11 Paper feed roller 12 TOP sensor 13 Fixing machine 14 Paper discharge sensor 15 Arrangement Tray 16 CPU
17 External interface 18 RAM
19 ROM
20 Image processing unit 21 RAM
22 ROM
23 Frame memory 24 Video interface 25 Engine controller part (engine part)
25a Engine controller 26 Video controller part (controller part)
30 CPU
31 RAM
32 flash ROM

Claims (5)

An interface device for connecting a control side and a controlled side,
Between the control side and the controlled side, there is a synchronization signal transmission means for transmitting a synchronization signal from the control side, and a serial data transmission / reception means for transmitting and receiving a data signal synchronized with the synchronization signal,
The control side includes instruction means for instructing the controlled side to perform predetermined processing,
The controlled side includes processing execution means for executing the predetermined processing from the controlling side,
The controlled side has a rewritable memory, and has a configuration for storing control program code data in the rewritable memory,
The control program code data rewriting means for rewriting the control program code data by transmitting the control program code data of the controlled side from the control side to the controlled side by the serial data transmitting / receiving means,
The serial transmission / reception data format when the control program code data rewrite is executed by the control program code data rewrite means is different from the transmission / reception data except when the control program code data rewrite is executed by means of a data format different from that of the transmission / reception data. An interface device comprising means for performing transmission / reception.   In the interface device having the above-described configuration, the serial transmission / reception data format has 16 bits as one data unit, and when rewriting the control program code, all 16 bits are defined as a data area, and the control program code is rewritten. 2. The interface apparatus according to claim 1, further comprising means for performing processing as transmission / reception data in a format in which 1-bit parity bit is added to 15-bit data, except when executing the above.   In the interface device having the above-described configuration, the serial transmission / reception data has 16 bits as one data unit, and when rewriting the control program code, all 16 bits are defined as a data area, and a plurality of predetermined data 2. The interface according to claim 1, further comprising means for transmitting / receiving one piece of data for confirming the consistency of a plurality of transmitted / received data at the time of transmitting / receiving the data, and performing a consistency confirmation process for the transmitted / received data. apparatus.   In the interface device configured as described above, when rewriting the control program code, transmission / reception data defining all 16 bits as a data area is address information and control program code data of the control program code on the controlled side The interface device according to claim 1.   An image forming apparatus comprising: a video controller unit that generates an image signal and an engine unit that prints and outputs the image signal generated by the video controller unit by the interface device configured as described above.

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