JP4626294B2 - Connection detection device and first device - Google Patents

Description

The present invention relates to a connection detection device that detects that two devices operating in cooperation with each other are connected to each other, and a first device used therefor.

For example, a connection detection device that detects the connection between a camera body and an external flash light emitting device includes a camera body with an internal flash light emitting device and a flash light emission control device built in, and an external flash light emitting device mounted outside the camera. (For example, Patent Document 1). In this type of connection detection device, the flash light emission control device detects whether or not the external flash light emission device is connected to the camera body. At this time, when detecting the connection between the camera body and the external flash light emitting device, the flash light emission control device permits the external flash light emitting device to emit light to the subject and prohibits the internal flash light emitting device from emitting light to the subject. On the other hand, if the connection between the camera body and the external flash light emitting device is not detected, the flash light emission control device permits only the internal flash light emitting device to emit light to the subject.
JP 2000-231145 A

  However, in the above-described connection detection device, when the shutter button of the camera body is pressed down immediately after the flash light emission control device is activated (the user takes a picture of the subject), the flash light emission control device is configured to irradiate the subject with light. In order to determine the flash light emitting device to be used, it is necessary to detect the connection between the camera body and the external flash light emitting device in a short time. Therefore, in order to quickly detect the connection between the camera body and the external flash light emitting device, a dedicated signal line for detecting the connection between the camera body and the external flash light emitting device is required. Further, for example, when the external flash light emitting device needs to detect the connection with the camera main body, the external flash light emitting device and the camera are detected in order to quickly detect the connection between the external flash light emitting device and the camera main body. A dedicated signal line for detecting the connection with the main body is required separately. For this reason, a total of two signal lines for detecting that the camera body and the external flash light emitting device are connected to each other are required.

An object of the present invention is to provide a connection detection device for detecting the connection of two devices operating in cooperation with each other, with a simple mechanism using only one signal line shared by the two devices, and whether there is a connection. It is providing the connection detection apparatus and 1st apparatus which detect rapidly.

In the connection detection device according to claim 1, the first and second resistors are provided in the first device, and are connected in series between the first voltage line and the second voltage line. The first connection terminal is provided in the first device, is connected to a first connection node that connects the first resistor and the second resistor to each other, and is connected to the second device via a connection line. The first detection unit is provided in the first device, and detects the connection between the first device and the second device according to the voltage of the first connection node. The third and fourth resistors are provided in the second device, and are connected in series between the third voltage line and the fourth voltage line. The second connection terminal is provided in the second device, is connected to a second connection node that connects the third and fourth resistors to each other, and is connected to the first connection terminal via a connection line. The second detection unit is provided in the second device, and detects the connection between the first device and the second device according to the voltage of the second connection node. The first detection unit is in a first state in which the second device is not connected to the first device, the second device is connected to the first device, and the second detection unit is detecting connection. The second threshold value and the first threshold value, the second threshold value, and the first connection node are the second state and the third state in which the second device is connected to the first device and the second detection unit is detecting connection. It detects based on the comparison with the voltage. The second detection unit is in a fourth state in which the first device is not connected to the second device, the first device is connected to the second device, and the first detection unit performs connection detection. The third threshold value, the fourth threshold value, and the second connection node, respectively, in the fifth state that is not present and the sixth state in which the first device is connected to the second device and the first detection unit detects the connection. It detects based on the comparison with the voltage.

In the connection detection device according to claim 2, the first power supply unit is provided in the first device, and sets the first and second voltages to the first and second voltage lines, respectively. The second power supply unit is provided in the second device, and sets the third and fourth voltages on the third and fourth voltage lines, respectively.
In the connection detection device according to claim 3, the first and third voltages are equal to each other, and the second and fourth voltages are equal to each other.

  According to a fourth aspect of the present invention, the first microcomputer has a first output port provided in the first device and connected to the first voltage line. The second microcomputer is provided in the second device and has a second output port connected to the third voltage line. The first microcomputer outputs the first voltage only when the connection to the second device is detected at the first output port. The second microcomputer outputs the second voltage only when the connection with the first device is detected at the second output port. The voltages of the second voltage line and the fourth voltage line are fixed.

  In the connection detection device according to claim 5, the first microcomputer starts from the first output port to set the first voltage line in a floating state except when detecting connection with the second device. Stops outputting the voltage of. The second microcomputer stops outputting the second voltage from the second output port in order to place the third voltage line in a floating state, except when detecting the connection with the first device. .

In the connection detection device according to the sixth aspect, the first microcomputer outputs a voltage equal to the voltage of the second voltage line from the first output port except when detecting the connection with the second device. The second microcomputer outputs a voltage equal to the voltage of the fourth voltage line from the second output port except when detecting connection with the first device.
The connection detection apparatus according to claim 7, wherein the first detection unit includes a first A / D converter that is connected to the first connection node and converts the voltage of the first connection node from an analog amount to a digital amount. Prepare. The second detection unit includes a second A / D converter that is connected to the second connection node and converts the voltage of the second connection node from an analog amount to a digital amount.

In the connection detection device according to the eighth aspect, the first microcomputer is provided in the first device. The second microcomputer is provided in the second device. The first A / D converter is built in the first microcomputer. The second A / D converter is built in the second microcomputer. According to a ninth aspect of the present invention, a second connection terminal that can connect a connection line and a device connected via the connection line and the second connection terminal are detected via the second connection terminal. A first device connectable to a second device including a detection unit, wherein the first resistor and the second resistor are connected in series between the first voltage line and the second voltage line; A first connection terminal connected to a first connection node connecting the first resistor and the second resistor to each other, and connected to a second device via a connection line; according to a voltage of the first connection node; A first detection unit that detects a connection between the first device and the second device, and the first detection unit includes a first detection unit in which the second device is not connected to the first device. 1 state, the 2nd state where the 2nd device is connected to the 1st device, and the 2nd detection part is not performing connection detection, and the 2nd state to the 1st device Each of the third states in which the detector is connected and the second detector is detecting the connection based on the first threshold and the comparison between the second threshold and the voltage of the first connection node. It is.

  In the connection detection device according to claim 1, the first detection unit transmits the second device to the first device according to a change in voltage of the first connection node connected to the second device via the connection line. Detect that is connected. On the other hand, in the second detection unit, the first device is connected to the second device in accordance with a change in voltage of the second connection node connected to the first connection node via the connection line described above. Is detected. That is, the connection between the first device and the second device is detected in both the first and second devices using only one connection line wired between the first and second devices. The Therefore, the mechanism for detecting the connection between the first device and the second device can be simplified. Since the number of manufacturing steps and the number of parts for manufacturing the connection detection device can be reduced, the manufacturing cost of the connection detection device can be reduced.

  In the connection detection device according to the second aspect, the first power supply unit can set at least one of the first and second voltage lines to a voltage different from the external power supply voltage. For example, when the external power supply voltage and the ground voltage are supplied to the first and second voltage lines by setting the first voltage line to a value lower than the external power supply voltage and the second voltage line to the ground voltage. In comparison, the voltage difference between the first and second voltage lines can be reduced. For this reason, the electric current which flows into the 1st and 2nd resistance can be made small. Therefore, the power consumed by the first and second resistors can be reduced. Also in the second power supply unit, as in the first power supply unit described above, the third and fourth voltage lines are set to a voltage different from the external power supply voltage by setting at least one of the third and fourth voltage lines. The current flowing through the resistor 4 can be reduced. Therefore, the power consumed by the third and fourth resistors can be reduced. As a result, the power consumed by the entire apparatus can be reduced.

  In the connection detection device according to claim 3, since the first and second voltages are set equal to the third and fourth voltages, respectively, the first and second voltages are the third and fourth voltages. Compared to different cases, the voltages of the first and second connection nodes can be obtained by a simple calculation formula. For this reason, the resistance values of the first to fourth resistors for detecting the voltages of the first and second connection nodes can be easily designed.

  In the connection detection device according to the fourth aspect, the predetermined voltage is output from the first output port only when the first microcomputer detects the connection between the first and second devices. For this reason, the power consumed by the first device can be reduced. A predetermined voltage is output from the second output port only when the connection of the first and second devices is detected by the second microcomputer. For this reason, the power consumed by the second device can be reduced. As a result, the power consumed by the entire apparatus can be reduced.

In the connection detection device according to the fifth aspect, the first and third voltage lines are set in a floating state except when the connection with the first and second devices is detected. For this reason, current does not flow through the first to fourth resistors except when the connection is detected. As a result, the power consumed by the entire apparatus can be reduced to zero.
In the connection detection device according to claim 6, the first and second voltages, and the third and fourth voltages are set to be equal to each other except when the connection with the first and second devices is detected. . For this reason, current does not flow through the first to fourth resistors except when the connection is detected. As a result, the power consumed by the entire apparatus can be reduced to zero.

  In the connection detection device according to the seventh aspect, the voltages detected at the first and second connection nodes are A / D converted by the first and second A / D converters, respectively. By acquiring the voltages detected at the first and second connection nodes as digital values, the voltages at the first and second connection nodes can be accurately detected. For this reason, the 1st detection part can compare correctly the voltage when the 1st and 2nd apparatus is connected, and the voltage when the 1st and 2nd apparatus is not connected. On the other hand, the second detection unit can accurately compare the voltage when the first and second devices are connected to the voltage when the first and second devices are not connected. As a result, it is possible to reliably detect the connection between the first and second devices.

  According to another aspect of the connection detection device of the present invention, the first and second A / D converters are built in the first and second microcomputers, respectively. For this reason, it is not necessary to provide the 1st and 2nd A / D converters independently. Therefore, since the connection detection device can be simply configured, the manufacturing cost of the connection detection device can be reduced.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows a first embodiment of the connection detection apparatus of the present invention. Fig.1 (a) has shown the front (front surface) of the connection detection apparatus. FIG. 1B shows the left side surface of the connection detection device 100. 1A and 1B, the connection detection device 100 includes a flash light emission control device 102 (first device) and a flash light emission device 104 (second device) attached to the camera body 108 of the digital camera system. ), And the flash light emission control device 102 and the flash light emission device 104 are connected to each other.

The flash light emission control device 102 receives a control signal output from the camera main body 108 and is detachably attached to an accessory shoe on the upper portion of the camera main body 108 in order to control the light emission operation of the flash light emission device 104. The flash light emission control device 102 includes a liquid crystal panel (not shown) and a driver circuit for driving the liquid crystal panel.
The liquid crystal panel of the flash light emission control device 102 is disposed on the back surface of the flash light emission control device 102. The screen displayed on the liquid crystal panel of the flash light emission control device 102 is switched for each operation mode of the connection detection device 100 described later. The flash light emission control device 102 has a function of detecting whether or not the flash light emission device 104 is connected via the cable 106.

  The flash light emitting device 104 is a macro flash for close-up used when the distance to the subject is short (for example, about 0.2 to 1 m). For this reason, the flash light emitting device 104 includes an annular mounting portion 104a that is detachably attached to the distal end portion of the photographing lens of the camera body 108, and two flash light emitting portions 104b and 104c that project laterally from the mounting portion 104a. And have.

In FIG.1 (b), the flash light emission part 104c has the setting part for adjusting a flash light quantity. Similar to the flash light emission control device 102, the flash light emission device 104 has a function of detecting whether or not the flash light emission control device 102 is connected via the cable 106.
The connection detection device 100 includes a first mode in which a control signal from the camera body 108 received by the flash light emission control device 102 is wired to the flash light emission device 104 via the cable 106, and a camera main body received by the flash light emission control device 102. There is a second mode in which a control signal from 108 is wirelessly transmitted to the flash light emitting device 104.

When it is detected that the flash light emission device 104 is connected to the flash light emission control device 102, the connection detection device 100 operates in the first mode. On the other hand, when it is detected that the flash light emission device 104 is not connected to the flash light emission control device 102, the connection detection device 100 operates in the second mode.
FIG. 2 shows details of the connection detection apparatus 100 of FIG. The flash light emission control device 102 includes a microcomputer 10 (first detection unit), a resistor R1 (first resistor), a resistor R2 (second resistor), a liquid crystal panel illumination circuit (not shown), and the like. The microcomputer 10 includes an A / D converter 12 (first A / D converter), an I / O port 14 (first output port), a CPU 16, a ROM and a RAM (not shown), and the like.

The A / D converter 12 is connected to the connection node 18 in order to detect whether or not the flash light emission device 104 is connected to the flash light emission control device 102. The A / D converter 12 A / D converts the voltage value of the connection node 18 and outputs the A / D converted voltage value data to the CPU 16.
The I / O port 14 is controlled by the CPU 16 and applies a power supply voltage Vcc1 (for example, 5.0 V) to one end of the resistor R1 only when detecting whether or not the flash light emission device 104 is connected to the flash light emission control device 102. Output. When the I / O port 14 does not detect whether the flash light emitting device 104 is connected to the flash light emission control device 102, the I / O port 14 supplies power to one end of the resistor R1 in order to place one end of the resistor R1 in a floating state (Hiz). The output of the voltage Vcc1 is stopped.

  The CPU 16 controls the operation of each peripheral circuit such as the A / D converter 12 and the I / O port 14 in the microcomputer 10 and the entire flash light emission control device 102 by executing a program stored in the ROM. The CPU 16 detects whether or not the flash light emission control device 102 has connected the flash light emission device 104 according to the voltage value data of the connection node 18 output from the A / D converter 12.

The resistors R1 and R2 are connected in series via the connection node 18 between the output terminal of the I / O port 14 and the ground line Vss. The resistance values of the resistors R1 and R2 are designed in advance to 10 kΩ and 33 kΩ, for example.
The flash light emitting device 104 includes a microcomputer 24 (second detection unit), a resistor R3 (third resistor), a resistor R4 (fourth resistor), a discharge circuit and a booster circuit (not shown), and the like. The microcomputer 24 includes an A / D converter 26 (second A / D converter), an I / O port 28 (second output port), a CPU 30, a ROM and a RAM (not shown), and the like.

The A / D converter 26 is connected to the connection node 32 in order to detect whether or not the flash light emission control device 102 is connected to the flash light emission device 104. The A / D converter 26 A / D converts the voltage value of the connection node 32 and outputs the A / D converted voltage value data to the CPU 30.
The I / O port 28 is controlled by the CPU 30 and only when it is detected whether or not the flash light emission control device 102 is connected to the flash light emission device 104, the power supply voltage Vcc2 (for example, 5.0V) equal to the power supply voltage Vcc1 described above. ) Is output to one end of the resistor R3. Since the power supply voltage Vcc2 is the same as the power supply voltage Vcc1, compared to the case where different power supply voltages are respectively set to one terminal of the resistor R1 and one terminal of the resistor R3, the connection node 18 has a simple calculation formula. , 32 voltage values can be obtained.

The I / O port 28 supplies the power supply voltage Vcc2 to one end of the resistor R3 in order to place one end of the resistor R3 in a floating state (Hiz) when the flash light emitting device 104 does not detect the presence or absence of connection of the flash light emission control device 102. Stop the output of.
The CPU 30 controls the operation of each peripheral circuit such as the A / D converter 26 and the I / O port 28 in the microcomputer 24 and the entire flash light emitting device 104 by executing a program stored in the ROM. The CPU 30 detects whether or not the flash light emitting device 104 has connected the flash light emission control device 102 according to the voltage value data of the connection node 32 output from the A / D converter 26.

The resistors R3 and R4 are connected in series via the connection node 32 between the output terminal of the I / O port 28 and the ground line Vss. The resistance values of R3 and R4 are designed in advance to 33 kΩ and 10 kΩ, for example.
The cable 106 includes a communication line 38 (connection line), a ground line 40, and a communication line 42. The communication line 38 connects the connection terminal 20 (first connection node) connected to the connection node 18 and the connection terminal 34 (second connection node) connected to the connection point 32 to each other.

The ground line 40 connects the Vss terminals 22 and 36 connected to the ground terminal to each other. The communication line 42 connects the flash light emission control device 102 and the flash light emission device 104 to each other in order to transmit the control information received from the camera body 108 by the strobe control device 102 to the flash light emission device 104.
FIG. 3 shows the relationship between the operation of the connection detection apparatus 100 and the voltage values and voltage division ratios of the connection nodes 18 and 32. The connection detection device 100 has six operation states 1 to 6. Furthermore, the operation state of the connection detection device 100 includes a state (states 1 to 3) in which it is detected whether or not the flash light emission device 104 is connected to the flash light emission control device 102, and a flash light emission control device 102 connected to the flash light emission device 104. It is divided into two groups of states (states 4 to 6) for detecting whether or not it has been done.

  First, states 1 to 3 for detecting whether or not the flash light emitting device 104 is connected to the flash light emission control device 102 will be described. In state 1, the flash light emitting device 104 is not connected to the flash light emitting control device 102 via the cable 106, and the I / O port 14 of the flash light emitting control device 102 outputs the power supply voltage Vcc1 to one end of the resistor R1. Is shown (ON state). In the state 1, the voltage value V1 of the connection node 18 is easily calculated from the following equation (1).

V1 = Vcc1 × R2 / (R1 + R2) (1)
The voltage value V1 of the connection node 18 is 3.84V from the equation (1). The voltage division ratio (V1 / Vcc1) of the connection node 18 at this time is 0.767.
In state 2, the flash light emission device 104 is connected to the flash light emission control device 102 via the cable 106, and the I / O port 14 of the flash light emission control device 102 outputs the power supply voltage Vcc1 to one end of the resistor R1. The state (ON state) is shown. In state 2, the I / O port 28 of the flash light emitting device 104 stops outputting the power supply voltage Vcc2 to one end of the resistor R3 in order to place one end of the resistor R3 in a floating state. In state 2, since no current flows through the resistors R3 and R4, the power consumed by the resistors R3 and R4 can be reduced to zero. Therefore, the power consumed by the connection detection device 100 can be reduced. In the state 2, the voltage value V1 of the connection node 18 is easily calculated from the following equation (2). “‖” In the equation (2) indicates a parallel resistance.

V1 = Vcc1 × (R2‖R4) / {R1 + (R2‖R4)} Expression (2)
The voltage value V1 of the connection node 18 is 2.17 V from the equation (2). The voltage division ratio (V1 / Vcc1) of the connection node 18 at this time is 0.434.
In state 3, the flash light emission device 104 is connected to the flash light emission control device 102 via the cable 106, and the I / O port 14 of the flash light emission control device 102 outputs the power supply voltage Vcc1 to one end of the resistor R1. The state (ON state) is shown. In state 3, the I / O port 28 of the flash light emitting device 104 outputs the power supply voltage Vcc2 to one end of the resistor R3. In the state 3, the voltage value V1 of the connection node 18 is easily calculated from the following equation (3). “‖” In equation (3) indicates a parallel resistance.

V1 = Vcc1 × (R2‖R4) / {(R1‖R3) + (R2‖R4)} (3)
The voltage value V1 of the connection node 18 is 2.50 V from the equation (3). At this time, the voltage dividing ratio (V1 / Vcc1) of the connection node 18 is 0.50.
The thresholds VT1 and VT2 for detecting the operation states 1 to 3 of the connection detection device 100 based on the voltage division ratios of the states 1 to 3 are, for example, 55 to 70% of Vcc1 and 45 to 49% of Vcc1. Respectively. When the voltage value V1 of the connection node 18 exceeds the threshold value VT1, the CPU 16 of the flash light emission control device 102 detects that the operation state of the connection detection device 100 is state 1. On the other hand, when the voltage value V1 of the connection node 18 is equal to or lower than the threshold value VT1 and exceeds the threshold value VT2, the CPU 16 of the flash light emission control device 102 detects that the operation state of the connection detection device 100 is state 3. On the other hand, the CPU 16 of the flash light emission control device 102 detects that the operation state of the connection detection device 100 is state 2 when the voltage value V1 of the connection node 18 is equal to or less than the threshold value VT2.

Next, states 4 to 6 in which the flash light emitting device 104 detects whether or not the flash light emission control device 102 is connected will be described. In state 4, the flash light emission control device 102 is not connected to the flash light emission device 104 via the cable 106, and the I / O port 28 of the flash light emission device 104 outputs the power supply voltage Vcc2 to one end of the resistor R3. Indicates the state (ON state). In the state 4, the voltage value V2 of the connection node 32 is easily calculated from the following equation (4).

V2 = Vcc2 × R4 / (R3 + R4) (4)
The voltage value V2 of the connection node 32 is 1.16V from the equation (4). At this time, the voltage dividing ratio (V2 / Vcc2) of the connection node 32 is 0.233.
State 5 is a state in which the flash light emission control device 102 is connected to the flash light emission device 104 via the cable 106, and the I / O port 28 of the flash light emission device 104 outputs the power supply voltage Vcc2 to one end of the resistor R3. (ON state). In state 5, the I / O port 14 of the flash light emission control device 102 stops the output of the power supply voltage Vcc1 to the one end of the resistor R1 so that the one end of the resistor R1 is in a floating state. . In state 5, since no current flows through the resistors R1 and R2, power consumed by the resistors R1 and R2 can be reduced to zero. Therefore, the power consumed by the connection detection device 100 can be reduced. In the state 5, the voltage value V2 of the connection node 32 is easily calculated from the following equation (5). “‖” In the equation (5) indicates a parallel resistance.

V2 = Vcc2 × (R2‖R4) / {R3 + (R2‖R4)} Expression (5)
The voltage value V2 of the connection node 32 is 0.94V. At this time, the voltage dividing ratio (V2 / Vcc2) of the connection node 32 is 0.189.
State 6 is a state in which the flash light emission control device 102 is connected to the flash light emission device 104 via the cable 106, and the I / O port 28 of the flash light emission device 104 outputs the power supply voltage Vcc2 to one end of the resistor R3. (ON state). In state 6, the I / O port 14 of the flash light emission control device 102 outputs the power supply voltage Vcc1 to one end of the resistor R1. In the state 6, the voltage value V2 of the connection node 32 is easily calculated from the following equation (6). “‖” In the equation (6) indicates a parallel resistance.

V2 = Vcc2 × (R2‖R4) / {(R1‖R3) + (R2‖R4)} (6) The voltage value V2 of the connection node 32 is 2.50V. At this time, the voltage dividing ratio of the connection node 32 is 0.5.
The thresholds VT3 and VT4 for detecting the operation states 4 to 6 of the connection detection device 100 based on the voltage division ratios in the states 4 to 6 are, for example, 25 to 45% of Vcc2 and 20 to 22% of Vcc2. Respectively. When the voltage value V2 of the connection node 32 exceeds the threshold value VT3, the CPU 30 of the flash light emitting device 104 detects that the operation state of the connection detection device 100 is state 6. On the other hand, when the voltage value V2 of the connection node 32 is equal to or less than the threshold value VT3 and exceeds the threshold value VT4, the CPU 30 of the flash light emitting device 104 detects that the operation state of the connection detection device 100 is state 4. On the other hand, the CPU 30 of the flash light emitting device 104 detects that the operation state of the connection detection device 100 is the state 5 when the voltage value V2 of the connection node 32 is equal to or less than the threshold value VT4.

  As described above, the CPU 16 of the flash light emission control device 102 sends the flash light emission control device 104 to the flash light emission control device 104 in accordance with a change in the voltage value of the connection node 18 connected to the flash light emission device 104 via the communication line 38. Detect whether or not is connected. On the other hand, the flash light emitting device 104 is connected to the flash light emitting device 104 in accordance with a change in the voltage value of the connection node 32 connected to the flash light emitting control device 102 via the communication line 38. It is detected whether or not. That is, in both the flash light emission control device 102 and the flash light emission device 104 using only one signal line 38 wired to the flash light emission control device 102 and the flash light emission device 104, the flash light emission control device 102 and the flash light emission device. 104 connections can be detected.

Since the I / O ports 14 and 28 set the same power supply voltages Vcc1 and Vcc2 to one terminal of the resistor R1 and one terminal of the resistor R3, respectively, voltages having different voltage values are set to one terminal of the resistor R1 and Compared to the case where each of the terminals of the resistor R3 is set, the voltage values of the connection nodes 18 and 32 can be obtained by a simple calculation formula.
FIG. 4 shows a comparative example of the connection detection apparatus 100 of the present invention. The connection detection device 38 includes a flash light emission control device DET1, a flash light emission device DET2, and a cable 44. The flash light emission control device DET1 includes a detection unit 46. The detection unit 46 detects whether or not the flash light emission device DET2 is connected to the flash light emission control device DET1 according to the voltage value of the connection terminal 50 for connecting the cable 44.

The flash light emitting device DET2 includes a detection unit 54. Similarly to the detection unit 46 described above, the detection unit 54 detects whether or not the flash light emission control device DET1 is connected to the flash light emission device DET2 in accordance with the voltage value of the connection terminal 56 for connecting the cable 44. .
The cable 44 includes communication lines 62 and 64 and a ground line 66. The communication line 62 is connected to the connection nodes 48 and 56, and is used to detect that the flash light emission control device DET2 is connected to the flash light emission device DET2. The communication line 64 is connected to the connection terminals 50 and 58 and is used to detect that the flash light emitting device DET2 is connected to the flash light emission control device DET1. The ground line 66 is used to connect the ground terminals 52 and 60 connected to the ground line Vss.

  The operation of the connection detection device 38 will be described. In the flash light emission control device DET1, the voltage value of the connection terminal 50 is always set to the power supply voltage Vcc by a pull-up resistor. Therefore, when the flash light emission device DET2 is not connected to the flash light emission control device DET1 via the cable 44, the detection unit 46 detects the power supply voltage Vcc as the voltage value of the connection terminal 50. On the other hand, when the flash light emission device 42 is connected to the flash light emission control device 40 via the cable 44, the connection terminal 50 is connected to the ground line Vss via the signal line 64. A ground voltage of 0 V is detected as a voltage value. As described above, the detection unit 46 detects whether or not the flash light emission device DET2 is connected to the flash light emission control device DET1 in accordance with a change in the voltage value of the connection terminal 50.

In the flash light emitting device DET2, the detection unit 54 detects the power supply voltage Vcc or the ground voltage 0V as the voltage value of the connection terminal 56 in the same manner as the detection operation of the flash light emission control device DET1 described above. The detection unit 56 detects whether or not the flash light emission control device DET1 is connected to the flash light emission device DET2 in accordance with a change in the voltage value of the connection terminal 50.
In the connection detection device 38 described above, the detection units 46 and 54 require separate communication lines 64 and 62 in order to detect the connection of the flash light emission control device DET1 and the flash light emission device DET2, respectively. This complicates the mechanism for detecting the connection between the flash light emission control device DET1 and the flash light emission device DET2. As a result, the manufacturing man-hours and the number of parts for manufacturing the connection detection device 38 increase, resulting in a problem that the manufacturing cost increases.

As described above, in this embodiment, the mechanism for detecting the connection between the flash light emission control device 102 and the flash light emission device 104 can be simplified. Since the number of manufacturing steps and the number of parts for manufacturing the connection detection device 100 can be reduced, the manufacturing cost of the connection detection device 100 can be reduced.
When it is not detected whether or not the flash light emitting device 104 is connected to the flash light emission control device 102, the I / O port 14 (or I / O port 28) causes one end of the resistor R1 (or resistor R3) to be in a floating state. Thus, the power consumed by the resistors R1 and R2 (or resistors R3 and R4) can be reduced to zero. Therefore, the power consumed by the connection detection device 100 can be reduced.

The A / D converter 12 of the flash light emission control device 102 and the A / D converter 26 of the flash light emission device 104 are incorporated in the microcomputers 10 and 24, respectively. For this reason, it is not necessary to provide the A / D converters 12 and 26 independently. Therefore, since the connection detection apparatus 100 can be configured easily, the manufacturing cost of the connection detection apparatus 100 can be reduced.
FIG. 5 shows a second embodiment of the connection detection apparatus of the present invention. The same elements as those described in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted. In this embodiment, a program stored in a ROM for execution by the CPU 16 and a program stored in a ROM for execution by the CPU 30 are different from those in the first embodiment of the connection detection device. The flash light emitting device 204 includes resistors R5 and R6 having resistance values different from those of the resistors R3 and R4, instead of the resistors R3 and R4 of the first embodiment. Other configurations are the same as those of the first embodiment. The connection detection device 200 includes a flash light emission control device 202 (first device), a flash light emission device 204 (second device), a flash light emission control device 202, and a flash light attached to the camera body 108 of the digital camera system shown in FIG. A cable 106 for connecting the light emitting device 204 to each other is provided.

  The flash light emission control device 202 includes a microcomputer 10 (first detection unit), a resistor R1 (first resistor), a resistor R2 (second resistor), a liquid crystal panel illumination circuit (not shown), and the like. The flash light emitting device 204 includes a microcomputer 24 (second detection unit), a resistor R5 (third resistor), a resistor R6 (fourth resistor), a discharge circuit and a booster circuit not shown. The resistors R5 and R6 are connected in series via the connection node 32 between the output terminal of the I / O port 28 and the ground line Vss. The resistance values of R5 and R6 are designed in advance to 56 kΩ and 27 kΩ, for example.

  FIG. 6 shows the relationship between the operation of the connection detection device 200 and the voltage values and voltage division ratios of the connection nodes 18 and 32. As in the first embodiment (FIG. 3), the connection detection device 200 is divided into a total of six patterns of six operating states 1-6. The operation state of the connection detecting device 200 includes a state (states 1 to 3) for detecting whether or not the flash light emitting device 204 is connected to the flash light emitting control device 202, and a state in which the flash light emitting control device 202 is connected to the flash light emitting device 204. It is divided into two groups of states (states 4 to 6) for detecting whether or not.

  The voltage division ratios (V1 / Vcc1) of the connection nodes 18 in the states 1 to 3 are 0.767, 0.598, and 0.636, respectively. The thresholds VT1 and VT2 for detecting the operation states 1 to 3 of the connection detection device 200 based on the voltage division ratios of the states 1 to 3 are, for example, 64 to 75% of Vcc1 and 60 to 63% of Vcc1. Respectively. When the voltage value V1 of the connection node 18 exceeds the threshold value VT1, the CPU 16 of the flash light emission control device 202 detects that the operation state of the connection detection device 200 is state 1. On the other hand, when the voltage value V1 of the connection node 18 is equal to or lower than the threshold value VT1 and exceeds the threshold value VT2, the CPU 16 of the flash light emission control device 202 detects that the operation state of the connection detection device 200 is state 3. On the other hand, the CPU 16 of the flash light emission control device 202 detects that the operation state of the connection detection device 200 is the state 2 when the voltage value V1 of the connection node 18 is equal to or less than the threshold value VT2.

  On the other hand, the voltage division ratios (V2 / Vcc2) of the connection nodes 32 in the states 4 to 6 are 0.325, 0.210, and 0.636, respectively. The thresholds VT3 and VT4 for detecting the operation states 4 to 6 of the connection detection device 200 based on the voltage division ratios of the states 4 to 6 are, for example, 33 to 62% of Vcc2 and 22 to 31% of Vcc2. Set to When the voltage value V2 of the connection node 32 exceeds the threshold value VT3, the CPU 30 of the flash light emitting device 204 detects that the operation state of the connection detection device 200 is state 6. On the other hand, when the voltage value V2 of the connection node 32 is equal to or less than the threshold value VT3 and exceeds the threshold value VT4, the CPU 30 of the flash light emitting device 204 detects that the operation state of the connection detection device 200 is state 4. On the other hand, when the voltage value V2 of the connection node 32 is equal to or lower than the threshold value VT4, the CPU 30 of the flash light emitting device 204 detects that the operation state of the connection detection device 200 is state 5. Compared to the case of the first embodiment (FIG. 3), the voltage value that can be used as the threshold value VT4 is increased by about 7%.

As described above, in this embodiment, the same effect as that of the first embodiment can be obtained. Furthermore, the degree of freedom in setting the threshold value VT4 for detecting the state 4 and the state 5 of the connection detection device 200 increases.
FIG. 7 shows a third embodiment of the connection detection apparatus of the present invention. The same elements as those described in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted. In this embodiment, a program stored in a ROM for execution by the CPU 16 and a program stored in a ROM for execution by the CPU 30 are different from those in the first embodiment of the connection detection device. Further, the flash light emission control device 302 and the flash light emission device 304 do not use the I / O ports 14 and 28 of the first embodiment, respectively, and one ends of the resistors R1 and R3 are directly connected to the external power supply voltages Vcc1 and Vcc2, respectively. Connected. Other configurations are the same as those of the first embodiment. The connection detection device 300 includes a flash light emission control device 302 (first device), a flash light emission device 304 (second device), and a flash light emission control device 302 that are attached to the camera body 108 of the digital camera system shown in FIG. It has the cable 106 which connects the flash light-emitting device 304 mutually.

The flash light emission control device 302 includes a microcomputer 68, a resistor R1 (first resistor), a resistor R2 (second resistor), a liquid crystal panel illumination circuit (not shown), and the like. The microcomputer 68 includes an A / D converter 12 (first A / D converter), a CPU 16 (first detection unit), ROM and RAM (not shown), and the like.
The flash light emitting device 304 includes a microcomputer 70, a resistor R3 (third resistor), a resistor R4 (fourth resistor), a discharge circuit and a booster circuit (not shown), and the like. The microcomputer 70 includes an A / D converter 26 (second A / D converter), a CPU 30, a ROM and a RAM (not shown), and the like.

  As described above, in this embodiment, the same effect as that of the first embodiment can be obtained. Further, by directly connecting one ends of the resistors R1 and R3 to the external power supply voltages Vcc1 and Vcc2, respectively, the mechanism for detecting the connection between the flash light emission control device 302 and the flash light emission device 304 can be simplified. Since the number of manufacturing steps and the number of parts for manufacturing the connection detection device 300 can be reduced, the manufacturing cost of the connection detection device 300 can be reduced.

  FIG. 8 shows a fourth embodiment of the connection detection apparatus of the present invention. The same elements as those described in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted. In this embodiment, the flash light emission control device 40 includes a detection unit 76 and a power supply unit 72 instead of the microcomputer 10 (A / D converter 12 and I / O port 14) of the first embodiment. ing. The flash light emitting device 404 includes a detection unit 78 and a power supply unit 74 instead of the microcomputer 24 (the A / D converter 26 and the I / O port 28) of the first embodiment. Other configurations are the same as those of the first embodiment. The connection detection device 400 includes a flash light emission control device 402 (first device), a flash light emission device 404 (second device), and a flash light emission control device 402 that are attached to the camera body 108 of the digital camera system shown in FIG. A cable 106 for connecting the flash light emitting device 404 to each other is provided.

The flash light emission control device 402 includes a power supply unit 72 (first power supply unit), a detection unit 76 (first detection unit), a resistor R1 (first resistor), a resistor R2 (second resistor), and an illustration. It has a lighting circuit for the liquid crystal panel.
The power supply unit 72 is connected to one end of the resistor R1. The power supply unit 72 applies a power supply voltage Vcc1 (for example, 5.0 V) lower than the external power supply voltage V to one end of the resistor R1 in order to detect whether or not the flashlight emission device 404 is connected to the flashlight emission control device 402. Output. For this reason, compared with the case where the external power supply voltage V is supplied to one end of the resistor R1, the voltage difference between the resistor R1 and the ground terminal can be reduced.

  The detection unit 76 is connected to the connection node 18 in order to detect whether or not the flash light emission device 404 is connected to the flash light emission control device 402. The detecting unit 76 receives the voltage value of the connection node 18 as an analog amount, and compares the received analog amount with preset threshold values VT1 and VT2. At this time, the detection unit 76 detects whether or not the flash light emission device 404 is connected to the flash light emission control device 402 based on the comparison result.

The flash light emitting device 404 includes a power supply unit 74 (second power supply unit), a detection unit 78 (second detection unit), a resistor R3 (third resistor), a resistor R4 (fourth resistor), and not shown. It has a discharge circuit, a booster circuit, and the like.
The power supply unit 74 is connected to one end of the resistor R3. The power supply unit 74 applies a power supply voltage Vcc2 (for example, 5.0 V) equal to the external power supply voltage Vcc1 to one end of the resistor R3 in order to detect whether or not the flashlight control device 402 is connected to the flashlight device 404. Output. For this reason, compared with the case where the external power supply voltage V is supplied to one end of the resistor R3, the voltage difference between the resistor R3 and the ground terminal can be reduced.

  The detection unit 78 is connected to the connection node 32 in order to detect whether or not the flash light emission control device 402 is connected to the flash light emission device 404. Similarly to the detection unit 76, the detection unit 78 receives the voltage value of the connection node 32 as an analog amount, and compares the received analog amount with preset threshold values VT3 and VT3. At this time, the detection unit 78 detects whether or not the flash light emission control device 402 is connected to the flash light emission device 404 based on the comparison result.

FIG. 10 shows details of the detection units 76 and 78. 10A and 10B show details of the detection units 76 and 78, respectively. The detectors 76 and 78 incorporate comparators 1 and 2 and comparators 3 and 4, respectively.
The comparator 1 inputs the voltage value V1 and the threshold value VT1 (for example, 55 to 70% of the power supply voltage Vcc1) of the connection node 18 as analog amounts. The comparator 1 compares the input analog quantities with each other, and outputs an H level signal when the voltage value V1 of the connection node 18 exceeds the threshold value VT1. On the other hand, the comparator 1 outputs an L level signal when the voltage value V1 of the connection node 18 is less than or equal to the threshold value VT1.

  Similarly to the comparator 1, the comparator 2 inputs the voltage value V1 and the threshold value VT2 (for example, 45 to 49% of the power supply voltage Vcc1) of the connection node 18 in analog quantities. The comparator 2 compares the input analog quantities with each other, and outputs an H level signal when the voltage value V1 of the connection node 18 exceeds the threshold value VT2. On the other hand, the comparator 2 outputs an L level signal when the voltage value V1 of the connection node 18 is less than or equal to the threshold value VT2.

Similar to the first embodiment (states 1 to 3 in FIG. 3), the detector 76 flashes the flash light emission control device 402 when the comparators 1 and 2 output the H level signal and the H level signal, respectively. A state is detected in which the device 404 is not connected via the cable 106 and the power supply unit 72 of the flash light emission control device 402 outputs the power supply voltage Vcc1 to one end of the resistor R1.
On the other hand, when the comparators 1 and 2 output the L level signal and the H level signal, the detection unit 76 is connected to the flash light emission control device 402 via the cable 106 and the flash light emission control device 402. The power supply unit 72 outputs a power supply voltage Vcc1 to one end of the resistor R1, and the power supply unit 74 of the flash light emitting device 404 detects a state in which the power supply voltage Vcc2 is output to one end of the resistor R3.

  On the other hand, when the comparators 1 and 2 output the L level signal and the L level signal, respectively, the detection unit 76 is connected to the flash light emission control device 402 via the cable 106 and the flash light emission control device 402. The power supply unit 72 outputs the power supply voltage Vcc1 to one end of the resistor R1, and the power supply unit 74 of the flash light emitting device 404 detects a state where the output of the power supply voltage Vcc2 is stopped to one end of the resistor R3.

  The comparator 3 inputs the voltage value V2 and the threshold value VT3 (for example, 25 to 45% of the power supply voltage Vcc2) of the connection node 32 in analog quantities. The comparator 3 compares the input analog quantities with each other, and outputs an H level signal when the voltage value V2 of the connection node 32 exceeds the threshold value VT3. On the other hand, the comparator 3 outputs an L level signal when the voltage value V2 of the connection node 32 is equal to or less than the threshold value VT3.

  Similar to the comparator 3, the comparator 4 inputs the voltage value V2 and the threshold value VT4 (for example, 20 to 22% of the power supply voltage Vcc2) of the connection node 32 in analog quantities. The comparator 4 compares the input analog quantities with each other, and outputs an H level signal when the voltage value V2 of the connection node 32 exceeds the threshold value VT4. On the other hand, the comparator 4 outputs an L level signal when the voltage value V2 of the connection node 32 is equal to or lower than the threshold value VT4.

  Similar to the first embodiment (states 4 to 6 in FIG. 3), when the comparators 3 and 4 both output an H level signal, the detector 78 connects the flash light emission control device 402 to the flash light emission device 404. 106, the power supply unit 72 of the flash light emission control device 402 outputs the power supply voltage Vcc1 to one end of the resistor R1, and the power supply unit 74 of the flash light emission device 404 outputs the power supply voltage Vcc2 to one end of the resistor R3. Is detected.

On the other hand, when the comparators 3 and 4 output the L level signal and the H level signal, respectively, the detection unit 78 does not connect the flash light emission control device 402 to the flash light emission device 404 via the cable 106 and flashes light. The power supply unit 74 of the device 404 detects a state where the power supply voltage Vcc2 is output to one end of the resistor R3.
On the other hand, when the comparators 3 and 4 output the L level signal and the L level signal, respectively, the detecting unit 78 is connected to the flash light emitting device 404 via the cable 106 and the flash light emitting control device 402. The power supply unit 72 stops the output of the power supply voltage Vcc1 to one end of the resistor R1, and the power supply unit 74 of the flash light emitting device 404 detects a state in which the power supply voltage Vcc2 is output to one end of the resistor R3.

  As described above, in this embodiment, the same effect as that of the first embodiment can be obtained. Furthermore, since the power consumed by the resistors R1 and R2 (or resistors R3 and R4) can be reduced as compared with the case where the external power supply voltage V is supplied to one end of the resistor R1 (or resistor R3), the connection detection device 400 The power consumed can be reduced. Further, even in a small-scale device such as a microcomputer that does not use an LSI, the flash light emission control device 402 and the flash light emission device 404 are both connected to the flash light emission control device 402 and the flash light emission device 404 with a single signal line. Connection can be detected.

  In the first embodiment of the connection detection device described above, when the flash light emission control device 102 and the flash light emission device 104 do not detect the presence or absence of mutual connection, the I / O ports 14 and 28 are connected to one end of the resistor R1 and the resistor R3. An example in which one end of the substrate is in a floating state has been described. The present invention is not limited to such an embodiment. For example, the I / O ports 14 and 28 may set one end of the resistor R1 and one end of the resistor R3 to the ground voltage Vss when the flash light emission control device 102 and the flash light emission device 104 do not detect the presence or absence of mutual connection. . Also in this case, since the current does not flow through the resistors R1, R2, R3, and R4 except when the presence / absence of connection between the flash light emission control device 102 and the flash light emission device 104 is detected, the current is consumed by the connection detection device 100. The power can be reduced to zero.

  Similarly, in the second embodiment of the connection detection device described above, when the flash light emission control device 202 and the flash light emission device 204 do not detect the presence or absence of mutual connection, the I / O ports 14 and 28 are connected to one end of the resistor R1 and the resistor. An example in which one end of R5 is in a floating state has been described. The present invention is not limited to such an embodiment. For example, the I / O ports 14 and 28 may set one end of the resistor 1 and one end of the resistor 3 to the ground voltage Vss when the flash light emission control device 202 and the flash light emission device 204 do not detect the presence or absence of the connection. . Also in this case, since the current does not flow through the resistors R1, R2, R3, and R4 except when the presence / absence of connection between the flash light emission control device 202 and the flash light emission device 204 is detected, the current is consumed by the connection detection device 200. The power can be reduced to zero.

In the first to fourth embodiments of the connection detection device described above, an example in which the connection detection device is applied to a camera system has been described. The present invention is not limited to such an embodiment. For example, the present invention may be applied to a connection detection device that detects a connection between two devices operating in cooperation.
As mentioned above, although this invention was demonstrated in detail, said embodiment and its modification are only examples of this invention, and this invention is not limited to this. Obviously, modifications can be made without departing from the scope of the present invention.

  The present invention is applied to a connection detection device that detects that two devices operating in cooperation with each other are connected to each other.

1 shows a first embodiment of a connection detection device of the present invention. The details of the connection detection apparatus 100 of FIG. 1 are shown. The relationship between the operation | movement of the connection detection apparatus 100, each voltage value and each voltage-dividing ratio of the connection nodes 18 and 32 is shown. The comparative example of the connection detection apparatus 100 of this invention is shown. 2 shows a second embodiment of the connection detection device of the present invention. The relationship between the operation | movement of the connection detection apparatus 200, each voltage value and each voltage-dividing ratio of the connection nodes 18 and 32 is shown. 3 shows a third embodiment of the connection detection device of the present invention. 4 shows a fourth embodiment of the connection detection device of the present invention. Details of the detectors 76 and 78 are shown.

Explanation of symbols

10, 24 Microcomputer 12, 26 A / D converter 14, 28 I / O port 16, 30 CPU
18, 32 Connection node 20, 22, 34, 36, 48, 50, 52, 56, 58, 60 Connection terminal 38, 42, 62, 64 Communication line 40, 66 Ground line 44, 106 Cable 46, 54, 76, 78 Detection unit 72, 74 Power supply unit 100, 200, 300, 400 Connection detection device 102, 202, 302, 402 Flash emission control device 104, 204, 304, 404 Flash emission device 108 Camera body R1, R2, R3, R4 , R5, R6 resistance

Claims (9)

A first resistor and a second resistor provided in the first device and connected in series between the first voltage line and the second voltage line;
A first connection terminal provided in the first device, connected to a first connection node connecting the first resistor and the second resistor to each other, and connected to the second device via a connection line; ,
A first detector that is provided in the first device and detects a connection between the first device and the second device according to a voltage of the first connection node;
A third resistor and a fourth resistor provided in the second device and connected in series between a third voltage line and a fourth voltage line;
A second connection provided in the second device, connected to a second connection node connecting the third resistor and the fourth resistor to each other, and connected to the first connection terminal via the connection line A terminal,
A second detection unit that is provided in the second device and detects a connection between the first device and the second device according to a voltage of the second connection node ;
The first detection unit is in a first state where the second device is not connected to the first device, the second device is connected to the first device, and the second detection unit is Each of the second state in which the connection detection is not performed and the third state in which the second device is connected to the first device and the second detection unit is performing the connection detection are respectively Detecting based on a comparison between a threshold and a second threshold and the voltage of the first connection node;
The second detection unit is in a fourth state in which the first device is not connected to the second device, the first device is connected to the second device, and the first detection unit is A third state in which the connection detection is not performed, and a sixth state in which the first device is connected to the second device and the first detection unit is performing the connection detection, respectively. A connection detection device that detects a threshold based on a comparison between a threshold value and a fourth threshold value and a voltage of the second connection node . The connection detection device according to claim 1,
A first power supply unit that is provided in the first device and sets the first and second voltages on the first and second voltage lines, respectively;
Wherein provided in the second device, the connection detecting apparatus characterized by comprising: a second power supply unit for setting the third and fourth voltage, respectively to said third and fourth voltage line. The connection detection device according to claim 2,
The connection detecting device, wherein the first and third voltages are equal to each other, and the second and fourth voltages are equal to each other. The connection detection device according to claim 1,
A first microcomputer provided in the first device and having a first output port connected to the first voltage line;
Wherein provided in the second device, and a second microcomputer having a second output port connected to said third voltage line,
The first microcomputer outputs the first voltage only when detecting the connection with the second device to the first output port,
The second microcomputer outputs the second voltage only when detecting the connection with the first device to the second output port,
The connection detection device, wherein voltages of the second voltage line and the fourth voltage line are fixed. The connection detection device according to claim 4,
The first microcomputer outputs the first voltage from the first output port in order to place the first voltage line in a floating state, except when detecting connection with the second device. Stop that and
The second microcomputer outputs the second voltage from the second output port in order to place the third voltage line in a floating state except when detecting connection with the first device. A connection detecting device characterized by stopping the operation. The connection detection device according to claim 4,
The first microcomputer outputs a voltage equal to the voltage of the second voltage line from the first output port, except when detecting connection with the second device,
The second microcomputer outputs a voltage equal to the voltage of the fourth voltage line from the second output port except when detecting a connection with the first device. apparatus. The connection detection device according to claim 1,
The first detection unit includes a first A / D converter connected to the first connection node and converting a voltage of the first connection node from an analog amount to a digital amount,
The second detection unit includes a second A / D converter that is connected to the second connection node and converts a voltage of the second connection node from an analog amount to a digital amount. apparatus. The connection detection device according to claim 7,
A first microcomputer provided in the first device;
And a second microcomputer provided in the second device,
The first A / D converter is built in the first microcomputer, and the second A / D converter is built in the second microcomputer. . A second connection terminal capable of connecting a connection line; and a second detection unit configured to detect connection between the connection line and the device connected via the second connection terminal via the second connection terminal. A first device connectable to the second device,
A first resistor and a second resistor connected in series between the first voltage line and the second voltage line;
A first connection terminal connected to a first connection node connecting the first resistor and the second resistor to each other, and connected to the second device via the connection line;
A first detector that detects a connection between the first device and the second device according to a voltage of the first connection node;
The first detection unit is in a first state where the second device is not connected to the first device, the second device is connected to the first device, and the second detection unit is Each of the second state in which the connection detection is not performed and the third state in which the second device is connected to the first device and the second detection unit is performing the connection detection are respectively The first device, wherein the detection is performed based on a comparison between a threshold value and a second threshold value and a voltage of the first connection node.

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