Electronic device and its control method, and accessory and its control method

Abstract

The present invention provides an electronic device and its control method, and an accessory and its control method. The electronic device capable of detachably attaching an accessory includes a first processing unit capable of communicating with the accessory through a first communication method and a second processing unit capable of communicating with the accessory through a second communication method. The first processing unit receives accessory information from the accessory through the first communication method. The second processing unit communicates with the accessory through the second communication method based on the accessory information. The electronic device has a first power state and a second power state, wherein the power of the second power state is lower than the power of the first power state. The first processing unit communicates with the accessory through the first communication method in both the first power state and the second power state. The second processing unit communicates with the accessory through the second communication method in the first power state and does not communicate with the accessory through the second communication method in the second power state.

Description

Technical Field

[0001] The present invention relates to an electronic device such as a camera device to which an accessory can be attached. Background Art

[0002] When a camera device (energizing the camera device) is started in a camera system in which an accessory such as a lighting device is attached to the camera device, the camera device usually detects the attachment of the accessory by switch detection or communication detection after the start is completed, and then obtains necessary information from the accessory. Japanese Unexamined Patent Application Publication No. 2016-218187 discloses the following camera device that obtains specific information from an accessory having a display function and then instructs the accessory to display the information.

[0003] The camera device can be started from a state in which communication with the accessory is not possible (such as a power-off state and a low power consumption (sleep) state). However, if information cannot be obtained from the accessory until the camera device is fully started, it takes time to obtain the information required to control the accessory. In particular, in the case where the camera device makes a control-related determination using information from the accessory, the responsiveness of the camera system is impaired due to this time lag. Summary of the Invention

[0004] The present invention provides an electronic device, a control method of the electronic device, an accessory, and a control method of the accessory, each of which can enhance the responsiveness at the time of starting in a system in which the accessory is attached to the electronic device.

[0005] An electronic device according to an aspect of the present invention is capable of detachably attaching an accessory, and includes: a first processing unit capable of communicating with the accessory by a first communication method; and a second processing unit capable of communicating with the accessory by a second communication method different from the first communication method. The first processing unit receives accessory information for identifying the accessory from the accessory by the first communication method. The second processing unit communicates with the accessory for controlling the accessory by the second communication method based on the accessory information. The electronic device has a first power state and a second power state, and the power of the second power state is lower than the power of the first power state. The first processing unit communicates with the accessory by the first communication method in the first power state and the second power state. The second processing unit communicates with the accessory by the second communication method in the first power state and does not communicate with the accessory by the second communication method in the second power state. The control method of the above electronic device also constitutes another aspect of the present invention.

[0006] An accessory according to another aspect of the present invention, which is detachably attachable to an electronic device. The accessory includes an accessory processing unit that can communicate with the electronic device by a first communication method and a second communication method different from the first communication method. The accessory processing unit sends accessory information for identifying the accessory to the electronic device by the first communication method, and after the accessory processing unit sends the accessory information, communicates with the electronic device by the second communication method for controlling the accessory. When the electronic device is in a first power state and a second power state, the accessory processing unit communicates with the electronic device by the first communication method, where the power of the second power state is lower than the power of the first power state. The accessory processing unit communicates with the electronic device by the second communication method when the electronic device is in the first power state, and does not communicate with the electronic device by the second communication method when the electronic device is in the second power state. The control method of the above accessory also constitutes another aspect of the present invention.

[0007] A control method for an electronic device that can detachably attach an accessory. The electronic device includes a first processing unit and a second processing unit. The control method includes the following steps: causing the first processing unit to receive accessory information for identifying the accessory from the accessory by a first communication method; causing the second processing unit to communicate with the accessory by a second communication method for controlling the accessory based on the accessory information, where the electronic device has a first power state and a second power state, and the power of the second power state is lower than the power of the first power state; causing the first processing unit to communicate with the accessory by the first communication method in the first power state and the second power state; and causing the second processing unit to communicate with the accessory by the second communication method in the first power state, and prohibiting the second processing unit from communicating with the accessory by the second communication method in the second power state.

[0008] A control method for an accessory, the accessory being detachably attached to an electronic device, the control method comprising the steps of: causing the accessory to send accessory information for identifying the accessory to the electronic device by a first communication method; after the accessory sends the accessory information, causing the accessory to communicate with the electronic device by a second communication method for controlling the accessory; causing the accessory to communicate with the electronic device by the first communication method when the electronic device is in a first power state and a second power state, wherein the power of the second power state is lower than the power of the first power state; and causing the accessory to communicate with the electronic device by the second communication method when the electronic device is in the first power state, and prohibiting the accessory from communicating with the electronic device by the second communication method when the electronic device is in the second power state.

[0009] More features of the present invention will become apparent from the following description of exemplary embodiments with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 Illustrate the structure of a camera system (including a camera, a lens unit, and an accessory) in the first embodiment.

[0011] Figure 2A and Figure 2B Illustrate the protocol of SPI communication in the first embodiment.

[0012] Figures 3A to 3D Illustrate a flowchart of the processes to be performed by the camera and the accessory in the first embodiment.

[0013] Figure 4 Illustrate the communication data in SPI communication in the first embodiment.

[0014] Figure 5 Illustrate the accessory information in the first embodiment.

[0015] Figure 6 Illustrate the processing sequence of the camera system in the first embodiment.

[0016] Figure 7 Illustrate the accessory type information in the first embodiment.

[0017] Figure 8 Illustrate the factors for generating a communication request in the first embodiment.

[0018] Figure 9A and Figure 9B Illustrate the communication interval in SPI communication in the first embodiment.

[0019] Figure 10The flowchart of the startup process to be performed by the camera (camera control circuit A) in the first embodiment is illustrated.

[0020] Figure 11 The flowchart of the startup process to be performed by the camera (camera control circuit B) in the first embodiment is illustrated.

[0021] Figure 12 The flowchart of the process to be performed by the accessory in the first embodiment is illustrated.

[0022] Figure 13 The startup sequence of the camera system in the first embodiment is illustrated.

[0023] Figure 14A and Figure 14B The startup sequence starting from the low power consumption mode in the second embodiment is illustrated.

[0024] Figure 15A and Figure 15B An example of the I2C communication waveform is illustrated.

[0025] Figure 16 The process to be performed by the camera when sending N bytes of data from the camera to the accessory in the first embodiment is illustrated.

[0026] Figure 17 The process to be performed by the camera when receiving N bytes of data from the accessory by the camera in the first embodiment is illustrated.

[0027] Figure 18A and Figure 18B The process to be performed by the accessory when communicating N bytes of data between the camera and the accessory in the first embodiment is illustrated.

[0028] Figure 19 The flowchart of the process when SW1 and SW2 are turned on simultaneously in the third embodiment is illustrated.

[0029] Figure 20 The flowchart of the process when SW1 and SW2 are turned on simultaneously in the comparative example is illustrated.

[0030] Figure 21 The flowchart of the live view display process in the fourth embodiment is illustrated.

[0031] Figure 22 The flowchart of the live view display process in the comparative example is illustrated. Detailed Description of the Invention

[0032] Embodiments of the present invention will now be described with reference to the accompanying drawings.

[0033] First Embodiment

[0034] Figure 1 An electrical configuration of an exemplary imaging system is illustrated. The imaging system includes an imaging device (hereinafter referred to as a camera) 100 that is an electronic device according to a first embodiment of the present invention, and an accessory 200 that is detachably attached to the imaging device. The accessory 200 is, for example, a microphone device or a lighting (strobe / flash) device, and includes various devices that can be attached to the camera 100. The camera 100 and the accessory 200 are electrically connected through one-to-one contact between a plurality of contacts (terminals) TC01 to TC21 of a camera connector 141 provided in the camera 100 and a plurality of contacts TA01 to TA21 of an accessory connector 211 provided in the accessory 200. The accessory 200 may not have a part of the plurality of contacts TA01 to TA21.

[0035] The camera 100 is powered by a battery 111. The battery 111 is attachable to and detachable from the camera 100. A camera control circuit A 101 that is a first processing unit and a receiving unit, and a camera control circuit B 102 that is a second processing unit in the camera 100 are circuits that control the entire camera 100, and include a processor (microcomputer) such as a CPU. The camera control circuit A 101 and the camera control circuit B 102 execute various controls and processes according to a computer program.

[0036] The camera control circuit A 101 monitors operations of switches and the like used for camera operations (not shown), and controls the system power supply according to user operations. The camera control circuit A 101 includes a low-power type processor that can operate even when the camera 100 is in a low power consumption mode (power saving mode or second power state) that is a standby state. On the other hand, the camera control circuit B 102 is responsible for controlling an image sensor 122, a display circuit 127, and the like. The camera control circuit B102 includes a processor that stops operating in the low power consumption mode but operates in a normal operation mode (first power state).

[0037] Although the camera control circuit A 101 and the camera control circuit B 102 include separate processors in the present embodiment, the two circuits may be provided in a single processor.

[0038] The system power supply circuit 112 is a circuit that generates the power to be supplied to each circuit in the camera 100, and includes a DC / DC converter circuit, a Low Drop Out (LDO), a charge pump circuit, etc. The 1.8V voltage generated by the system power supply circuit 112 that receives power from the battery 111 is constantly supplied to the camera control circuit A 101 as the camera microcomputer power supply VMCU_C. Several types of voltages generated by the system power supply circuit 112 are supplied to the camera control circuit B 102 as the camera microcomputer power supply VMCU2_C at an arbitrary timing. The camera control circuit A 101 controls the on and off of the power supply to each circuit in the camera 100 by controlling the system power supply circuit 112.

[0039] The optical lens 121 can be attached to and detached from the camera 100. The light from the subject incident through the optical lens 121 is imaged on an image sensor 122 including a CMOS sensor, a CCD sensor, etc. The optical lens 121 and the camera 100 can be integrated. The subject image formed on the image sensor 122 is encoded into a digital video signal. The image processing circuit 123 performs image processing such as noise reduction processing and white balance processing on the digital video signal to generate image data, and converts the image data into an image file in the JPEG format, etc., to record the image data in the recording memory 126. The image processing circuit 123 generates VRAM image data to be displayed on the display circuit 127 from the image data.

[0040] The memory control circuit 124 controls the transmission and reception of the image data and other data generated by the image processing circuit 123, etc. The volatile memory 125 is a memory such as DDR3 SDRAM that can perform high-speed reading and writing, and is used as a work space for the image processing performed by the image processing circuit 123. The recording memory 126 is a readable and writable recording medium such as an SD card or a CFExpress card that can be attached to and detached from the camera 100 via a connector (not shown). The display circuit 127 is a display arranged on the back surface of the camera 100, and includes an LCD panel, an organic EL display panel, etc. The backlight circuit 128 adjusts the brightness of the display circuit 127 by changing the light amount of the backlight of the display circuit 127.

[0041] In this embodiment, the accessory power supply circuit A (hereinafter referred to as the accessory power supply circuit A) 131 and the accessory power supply circuit B (hereinafter referred to as the accessory power supply circuit B) 132 are each a voltage conversion circuit that converts the voltage supplied from the system power supply circuit 112 into a predetermined voltage, and generates 3.3V as the accessory power supply VACC. This configuration can convert the voltage into another voltage.

[0042] The accessory power supply circuit A 131 is a power supply circuit including an LDO or the like and having low self-power consumption. The accessory power supply circuit B 132 includes a DC / DC converter circuit or the like, and can pass a current larger than that of the accessory power supply circuit A 131. The self-power consumption of the accessory power supply circuit B 132 is greater than that of the accessory power supply circuit A 131. Therefore, when the load current is small, the accessory power supply circuit A 131 is more efficient than the accessory power supply circuit B 132, and when the load current is large, the accessory power supply circuit B 132 is more efficient than the accessory power supply circuit A 131. The camera control circuit A 101 controls the on and off of the voltage output of the accessory power supply circuits A 131 and B 132 according to the operation state of the accessory 200.

[0043] The protection circuit 133 includes a current fuse element, or an electronic fuse circuit combining multiple switching elements or resistors, an amplifier, and a switching element. When the power supply current value supplied from the accessory power supply circuits A 131 and B 132 to the accessory 200 is higher than a predetermined value and becomes excessive (abnormal), the protection circuit 133 outputs an overcurrent detection signal DET_OVC. In this embodiment, the protection circuit 133 is an electronic fuse circuit, and in the case where a current of 1 A or more flows, it notifies the camera control circuit A 101 of the overcurrent detection signal DET_OVC. The overcurrent detection signal DET_OVC indicates an overcurrent by becoming high level. The predetermined value may be different from 1 A.

[0044] The camera connector 141 is a connector for electrically connecting to the accessory 200 via 21 contacts TC01 to TC21 arranged in a row. The contacts TC01 to TC21 are arranged in the order of contacts TC01 to TC21 from one end to the other end in the arrangement direction.

[0045] TC01 is connected to the ground terminal (GND), and is used not only as a reference potential contact but also as a contact for controlling the wiring impedance of the differential signals D1N and D1P. TC01 corresponds to the third ground contact.

[0046] The differential signal D1N connected to TC02 and the differential signal D1P connected to TC03 are differential data communication signals for paired data communication, and are connected to the camera control circuit B 102. TC02, TC03, TC07 to TC10, TC12 to TC17, TC19, and TC20, which will be described below, are communication contacts.

[0047] TC04, which is the first ground contact, is connected to GND and serves as a reference potential contact for the camera 100 and the accessory 200. TC04 is arranged outside TC05 described below in the contact arrangement direction.

[0048] The accessory power supply (output signal) VACC generated by the accessory power supply circuits A 131 and B 132 is connected to TC05 serving as a power supply contact via the protection circuit 133.

[0049] The accessory attachment detection signal (first input signal) / ACC_DET is connected to TC06 serving as an attachment detection contact. The accessory attachment detection signal / ACC_DET is pulled up to the camera microcomputer power supply VMCU_C via a resistor element RP134 (such as 10 kΩ or the like). The camera control circuit A 101 can detect whether the accessory 200 is attached by reading the signal level of the accessory attachment detection signal / ACC_DET. If the signal level (potential) of the accessory attachment detection signal / ACC_DET is high (predetermined potential), it is detected that the accessory 200 is not attached, and if the signal level (potential) of the accessory attachment detection signal / ACC_DET is low level (GND potential) as an activation potential, it is detected that the accessory 200 is attached.

[0050] When the camera 100 is powered on, changing the signal level (potential) of the accessory attachment detection signal / ACC_DET from high level (Hi) to low level (Lo) triggers various transmissions via the contacts between the camera 100 and the accessory 200.

[0051] The camera control circuit 101 supplies power to the accessory 200 via TC05 serving as a power supply contact in response to detecting the attachment of the accessory 200.

[0052] SCLK connected to TC07 serving as a communication contact, MOSI connected to TC08, MISO connected to TC09, and Chip Select (CS) connected to TC10 are signals used for communication by the serial peripheral interface (SPI) communication method as a second communication method (hereinafter referred to as SPI communication), where the camera control circuit B 102 becomes a communication master in the second communication method. SCLK is a clock signal, MOSI is a transmission signal, MISO is a reception signal, and CS is a communication selection signal used as a signal for selecting a communication partner. In this embodiment, the SPI communication has a communication clock frequency of 1 MHz, a data length of 8 bits (1 byte), a bit order with MSB first, and a full-duplex communication method.

[0053] In this embodiment, the camera 100 and the accessory 200 support two types of communication protocols of the SPI communication method. The communication protocol A is a communication method in which the camera 100 does not confirm whether the accessory 200 is in a communicable state before outputting SCLK, and is referred to as SPI protocol A in the following description. Figure 2AOutline of the communication waveform of the exemplary SPI protocol A. In this figure, CS is active low.

[0054] The camera control circuit B 102 changes CS to low level (active) at timing A1 and requests SPI communication from the accessory control circuit 201.

[0055] At timing A2, which is a predetermined time T_CS after timing A1, the camera control circuit B 102 starts outputting SCLK and MOSI. When the accessory control circuit 201 detects the trailing edge of SCLK, the accessory control circuit 201 starts outputting MISO.

[0056] The camera control circuit B 102 stops outputting SCLK at timing A3 when it has finished outputting 1 byte of SCLK.

[0057] The camera control circuit B 102 stops outputting SCLK at timing A3 and continues for a predetermined time T_INTERVAL. After T_INTERVAL has elapsed, at timing A4, it restarts outputting SCLK and performs the next 1-byte communication.

[0058] Figure 3A The flowchart in [Figure number] illustrates the processing to be performed by the camera control circuit B 102 in the SPI protocol A. S represents steps.

[0059] In S101, the camera control circuit B 102 stores the value representing the number of bytes to be communicated in the internal variable N. For example, it stores 3 in the case of 3-byte communication.

[0060] In S102, the camera control circuit B 102 changes CS to low level and requests SPI communication.

[0061] In S103, the camera control circuit B 102 performs a wait process until a predetermined time T_CS has elapsed after CS has been changed to low level. After the predetermined time T_CS has elapsed, the flow proceeds to S104.

[0062] In S104, the camera control circuit B 102 controls SCLK output, MOSI data output, and MISO data input, and performs 1-byte data communication.

[0063] In S105, the camera control circuit B 102 checks whether the internal variable N representing the number of communication bytes is 0. If the internal variable N is 0, the flow proceeds to S106, and if the internal variable N is not 0, the flow proceeds to S107.

[0064] In S107, the camera control circuit B 102 stores, as a new internal variable N, the value obtained by decrementing by 1 the value of the internal variable N representing the number of communication bytes.

[0065] In S108, the camera control circuit B 102 performs a wait process until a predetermined time T_INTERVAL has elapsed after the completion of the 1-byte data communication in S104. Then, after the predetermined time T_INTERVAL has elapsed, the process returns to the process of S104, and the same process is executed again.

[0066] In S106, the camera control circuit B 102 changes CS to a high level and ends a series of SPI communications.

[0067] Figure 3B The flowchart in [ ] illustrates the processes to be performed by the accessory control circuit 201 in the SPI protocol A.

[0068] In S201, the accessory control circuit 201 confirms whether CS has changed to a low level. If CS has changed to a low level, the process proceeds to S202, and if CS has not changed to a low level, the process returns to S211.

[0069] In S202, in response to the input of the SCLK signal, the accessory control circuit 201 performs 1-byte data communication through MOSI data input control and MISO data output control.

[0070] In S203, the accessory control circuit 201 confirms whether CS has changed to a high level. If CS has changed to a high level, it is determined that the SPI communication is complete, and if CS has not changed to a high level, the process returns to S202 for the next 1-byte communication.

[0071] The communication protocol B in the SPI communication method is a communication method in which the camera 100 confirms whether the accessory 200 is in a communicable state before outputting the SCLK, and is referred to as the SPI protocol B in the following description. Figure 2B Illustrate the outline of the communication waveform of the SPI protocol B.

[0072] The camera control circuit B 102 changes CS to a low level at timing B1 and requests SPI communication from the accessory control circuit 201. The camera control circuit B 102 confirms the potential of MISO together with the communication request. If MISO is at a high level, it is determined that the accessory control circuit 201 is in a communicable state, and if MISO is at a low level, it is determined that the accessory control circuit 201 is in a non-communicable state.

[0073] On the other hand, when the accessory control circuit 201 detects the trailing edge of CS at timing B2, the accessory control circuit 201 controls to change MISO to high level when SPI communication is available, and controls to change MISO to low level when the communication is unavailable.

[0074] When the camera control circuit B 102 confirms that MISO is at high level at timing B3, the camera control circuit B102 starts to output SCLK and MOSI. The accessory control circuit 201 starts to output MISO when detecting the trailing edge of SCLK.

[0075] When 1-byte SCLK output is completed at timing B4, the camera control circuit B 102 stops outputting SCLK.

[0076] After 1-byte communication, as shown in timings B5 and B6, the accessory control circuit 201 controls to change MISO to high level when SPI communication is available, and controls to change MISO to low level when SPI communication is unavailable.

[0077] The camera control circuit B 102 confirms the potential of MISO at timing B7. If MISO is at high level, it is determined that the accessory control circuit 201 is in a communicable state, and if MISO is at low level, it is determined that the accessory control circuit 201 is in a non-communicable state.

[0078] Figure 3C The flowchart in shows the processing to be performed by the camera control circuit B 102 in the SPI protocol B.

[0079] In S111, the camera control circuit B 102 stores the value representing the number of bytes to be communicated in the internal variable N. For example, 3 is stored in the case of 3-byte communication.

[0080] In S112, the camera control circuit B 102 changes CS to low level and requests SPI communication.

[0081] In S113, the camera control circuit B 102 confirms whether MISO changes to high level. If MISO is at high level, the process proceeds to S114, and if MISO is not yet at high level, the process returns to S113.

[0082] In S114, the camera control circuit B 102 controls SCLK output, MOSI data output, and MISO data input to perform 1-byte data communication.

[0083] In S115, the camera control circuit B 102 confirms whether the communication of all data has been completed (whether the internal variable N representing the number of communication bytes is 0). If the internal variable N is 0, the process proceeds to S116, and if the internal variable N is not 0, the process proceeds to S117.

[0084] In S117, the camera control circuit B 102 stores the value obtained by decrementing the value of the internal variable N representing the number of communication bytes by 1 as the new internal variable N.

[0085] In S118, the camera control circuit B 102 confirms whether MISO changes to a high level. If MISO is at a high level, the process proceeds to S114, and if MISO is not at a high level, the process returns to S118.

[0086] In S116, the camera control circuit B 102 changes CS to a high level and ends a series of SPI communications.

[0087] Figure 3D The flowchart in [ ] illustrates the processing to be performed by the accessory control circuit 201 in the SPI protocol B.

[0088] In S211, the accessory control circuit 201 confirms whether CS changes to a low level. If CS changes to a low level, the process proceeds to S212, and if CS does not change to a low level, the process returns to S211.

[0089] In S212, the accessory control circuit 201 confirms whether SPI communication is available. If SPI communication is available, the process proceeds to S213, and if SPI communication is not available, the process proceeds to S214.

[0090] In S213, the accessory control circuit 201 performs control to change MISO to a high level, and the process proceeds to S215.

[0091] In S214, the accessory control circuit 201 performs control to change MISO to a low level, and the process returns to S212.

[0092] In S215, the accessory control circuit 201 controls MOSI data input and MISO data output in response to the SCLK signal input and performs 1-byte data communication.

[0093] In S216, the accessory control circuit 201 confirms whether CS changes to a high level. If CS changes to a high level, it is determined that the SPI communication is completed, and if CS does not change to a high level, the process returns to S212 for the next 1-byte communication.

[0094] Figure 4 Illustrate the communication content when notifying an operation execution instruction (command) from the camera 100 to the accessory 200 through SPI communication in this embodiment.

[0095] The camera control circuit B 102 sends the information CMD representing the command number as MOSI data to the accessory control circuit 201 in the first-byte communication. The accessory control circuit 201 sends the value 0xA5 as the information representing the communicable state as MISO data to the camera control circuit B 102. In the case where the first-byte communication process cannot be executed, the accessory control circuit 201 sends a value other than 0xA5 as MISO data to the camera control circuit B 102.

[0096] The camera control circuit B 102 sends the argument MOSI_DATA1 corresponding to the command number CMD to the accessory control circuit 201 in the second-byte communication. Then, from the third byte to the (N - 2)th byte, the arguments MOSI_DATA2 to MOSI_DATA[N - 3] corresponding to the command number CMD are similarly sent to the accessory control circuit 201.

[0097] The accessory control circuit 201 sends the command number CMD received in the first byte as MISO data to the camera control circuit B 102 in the second-byte communication. This configuration enables the camera control circuit B 102 to determine that the accessory control circuit 201 has correctly received the MOSI data.

[0098] The accessory control circuit 201 sends the return value MISO_DATA1 corresponding to the command number CMD as MISO data to the camera control circuit B 102 in the third-byte communication. Then, from the fourth byte to the (N - 2)th byte, the return values MISO_DATA2 to MISO_DATA[N - 4] corresponding to the command number CMD are similarly sent to the camera control circuit B 102.

[0099] It is assumed that the number of arguments and the number of return values are predetermined for each command number. One or both of the arguments and the return values can be omitted.

[0100] The camera control circuit B 102 sends the checksum data CheckSum_C as MOSI data to the accessory control circuit 201 in the (N - 1)th byte communication. The checksum data CheckSum_C is a value calculated by the following expression.

[0101] CheckSum_C = EXOR(AND(SUM(CMD, MOSI_DATA1, …, MOSI_DATA[N - 3]), 0xFF), 0xFF)

[0102] The accessory control circuit 201 sends 0x00 as the MISO data.

[0103] Next, the camera control circuit B 102 sends 0x00 as the MOSI data to the accessory control circuit 201 in the Nth byte communication.

[0104] The accessory control circuit 201 sends the checksum data CheckSum_A as the MISO data. The checksum data CheckSum_A is calculated by the following expression when the value of CheckSum_C received by the camera control circuit B 102 in the (N - 1)th byte communication is the same as the value of CheckSum_C calculated by the camera control circuit B 102.

[0105] CheckSum_A = EXOR(AND(SUM(0xA5, CMD, MIS0_DATA1, …, MOSI_DATA[N - 4]), 0xFF), 0xFF)

[0106] On the other hand, if the value of CheckSum_C received by the camera control circuit B 102 in the (N - 1)th byte communication is not the same as the value of CheckSum_C calculated by the camera control circuit B 102, then this value is calculated by the following expression.

[0107] CheckSum_A = AND(SUM(0xA5, CMD, MIS0_DATA1, …, MOSI_DATA[N - 4]), 0xFF)

[0108] Figure 1 The shown TC11 as the signal contact (communication request contact) is connected to the communication request signal (second input signal) / WAKE for requesting communication from the accessory 200 to the camera 100 (camera control circuit A 101). The communication request signal / WAKE is pulled up to the camera microcomputer power supply VMCU_C via a resistor. The camera control circuit A 101 can detect the communication request from the accessory 200 by detecting the change (trailing edge) of the communication request signal / WAKE.

[0109] The SDA connected to TC12 as a communication contact and the SCL connected to TC13 are signals for performing inter-integrated circuit (I2C) communication (hereinafter referred to as I2C communication) as a first communication method, where the camera control circuit A 101 is the communication master device in the first communication method. SDA is a data signal and SCL is a clock signal. SDA and SCL are open-drain communications pulled up by the camera microcomputer power supply VMCU_C, and have a communication frequency of 100 kbps in this embodiment.

[0110] In I2C communication, both data transmission from the camera 100 and data transmission from the accessory 200 are performed via SDA. When comparing SPI communication and I2C communication with each other, the communication speed of I2C communication is lower than that of SPI communication. The communication speed of SPI communication is higher than that of I2C communication, so it is suitable for information communication with a large amount of data. Therefore, in the communication between the camera 100 and the accessory 200 in this embodiment, information with a large amount of data is communicated by using SPI communication, and information with a small amount of data is communicated by using I2C communication. For example, data is first communicated by using I2C communication, and when SPI communication is available or needs to be executed based on this data, control can be performed to further execute SPI communication.

[0111] Figure 15A and Figure 15B Examples of I2C communication waveforms are illustrated. Figure 15A Examples of waveforms are illustrated in the case where the camera sends N-byte data (DATA[1] to DATA[N]) to the accessory, and Figure 15B Examples of waveforms are illustrated in the case where the camera receives N-byte data (DATA[1] to DATA[N]) from the accessory. In Figure 15A and Figure 15B , the upper waveform illustrates SCL, and the lower waveform illustrates SDA.

[0112] Below the SDA waveform, the meaning of the signals at each timing and the control circuit for controlling the output level of the SDA signal are illustrated, whether it is the camera control circuit A 101 or the accessory control circuit 201. The communication data includes data in 1-byte units and 1-bit information indicating a response. The upper part of each figure illustrates the number of bytes of data from the start of communication.

[0113] Since the details of the communication content will be described below with reference to Figures 16 to 18A and Figure 18B , the overview will be described with reference to Figure 15A and Figure 15B .

[0114] In Figure 15AIn the first-byte communication and the second-byte communication, the camera control circuit A 101 notifies the accessory control circuit 201 of the storage address information related to the data to be transmitted. In the third-byte communication to the (N + 2)-byte communication, the camera control circuit A 101 transmits N bytes of data (DATA[address] to DATA[address + N]) to the accessory control circuit 201.

[0115] In Figure 15B In the first-byte communication and the second-byte communication, the camera control circuit A 101 notifies the accessory control circuit 201 of the storage address information related to the data to be received. In the third-byte communication to the (N + 3)-byte communication, the camera control circuit A 101 receives N bytes of data (DATA[address] to DATA[address + N]) from the accessory control circuit 201.

[0116] Figure 16 The flowchart in shows the processing to be performed by the camera control circuit A 101 when the camera control circuit A 101 transmits N bytes of data to the accessory control circuit 201.

[0117] In S3001, the camera control circuit A 101 stores the value representing the number of bytes to be transmitted in the internal variable N. For example, when transmitting 3 bytes, 3 is stored. In this embodiment, 3 is stored.

[0118] In S3002, the camera control circuit A 101 changes SDA to low level while SCL is at high level (start condition). Thereby, it notifies the accessory control circuit 201 of the start of communication.

[0119] In S3003, the camera control circuit A 101 sets the slave address information representing the slave address of the accessory control circuit 201 to the high 7 bits of the data to be transmitted. In this embodiment, it is assumed that the slave address of the accessory control circuit 201 is 1010000 in binary.

[0120] In S3004, the camera control circuit A 101 sets the information representing the write communication to the low 1 bit of the data to be transmitted. Setting this bit to 0 means write communication.

[0121] In S3005, the camera control circuit A 101 transmits the data set as the data to be transmitted in S3003 and S3004 to the accessory control circuit 201 (10100000 in binary and 0xA0 in hexadecimal).

[0122] In S3006, after the camera control circuit A 101 sends 1-byte data, it outputs SCL and maintains it for one clock, and confirms the signal level of SDA. When the signal level of SDA is low, it is determined as a data reception notification (ACK) from the accessory control circuit 201, and the process proceeds to S3007. On the other hand, when the signal level of SDA is high, it is determined that the accessory control circuit 201 has not received the data normally, and the process proceeds to S3014.

[0123] In S3007, the camera control circuit A 101 sets the storage address information (start address information) of the data to be sent to the accessory control circuit 201 into the data to be sent. In this embodiment, the size of the start address information is 1 byte, and the value is 0x00.

[0124] In S3008, the camera control circuit A 101 sends the set 1-byte start address information (value 0x00) to the accessory control circuit 201.

[0125] In S3009, after the camera control circuit A 101 sends 1-byte start address information data, it outputs SCL and maintains it for one clock, and confirms the signal level of SDA. When the signal level of SDA is low, it is determined as a data reception notification (ACK) from the accessory control circuit 201, and the process proceeds to S3010. On the other hand, when the signal level of SDA is high, it is determined that the accessory control circuit 201 has not received the data normally, and the process proceeds to S3014.

[0126] In S3010, the camera control circuit A 101 stores 1 in the internal variable M. The internal variable M is a variable used to count the number of data to be sent.

[0127] In S3011, the camera control circuit A 101 outputs 1-byte data to the accessory control circuit 201 by outputting 1-byte SCL and changing SDA to the desired signal level during the period when SCL is at a low level. Here, the start address information is 0x00 and the internal variable M is 1, so 1-byte data corresponding to the address 0x00 is sent.

[0128] In S3012, after the camera control circuit A 101 sends 1-byte data, it outputs SCL and maintains it for one clock, and confirms the signal level of SDA. When the signal level of SDA is low, it is determined as a data reception notification (ACK) from the accessory control circuit 201, and the process proceeds to S3013. On the other hand, when the signal level of SDA is high, it is determined that the accessory control circuit 201 has not received the data normally, and the process proceeds to S3014.

[0129] In S3013, the camera control circuit A 101 confirms whether the internal variable M has the same value as the internal variable N. If the internal variable M has the same value as the internal variable N, it is determined that the transmission of all data is completed, and the process proceeds to S3014. If the internal variable M does not have the same value as the internal variable N, it is determined that there is still data to be transmitted, and the process proceeds to S3015.

[0130] In S3015, the camera control circuit A 101 adds 1 to the internal variable M, and the process returns to S3011.

[0131] Therefore, after the process returns to S3011, the camera control circuit A 101 sequentially increments the address of the data to be transmitted and transmits 1-byte data corresponding to each address. In this way, the camera control circuit A 101 transmits N-byte data to the accessory control circuit 201 by repeating the transmission of 1-byte data until the internal variable M and the internal variable N have the same value in the process of S3013. When the internal variable N is set to 3 as in this embodiment, 3-byte data can be transmitted.

[0132] In S3014, the camera control circuit A 101 changes SDA to high level (STOP condition) while SCL is at high level. Thereby, it notifies the accessory control circuit 201 of the end of communication.

[0133] Figure 17 The flowchart in shows the processing to be performed by the camera control circuit A 101 when the camera control circuit A 101 receives N-byte data from the accessory control circuit 201.

[0134] In S3101, the camera control circuit A 101 stores the numerical value representing the number of bytes to be received in the internal variable N. For example, when 3-byte data is received, 3 is stored. In this embodiment, 3 is stored.

[0135] In S3102 to S3106, the camera control circuit A 101 performs the same processing as in S3002 to S3006 respectively, so the description thereof will be omitted.

[0136] In S3107, the camera control circuit A 101 sets the storage address information (start address information) of the data received from the accessory control circuit 201 to the transmission data. In this embodiment, the size of the start address information is 1 byte, and the value is 0x00.

[0137] In S3108, the camera control circuit A 101 sends the set 1-byte start address information (value 0x00) to the accessory control circuit 201.

[0138] In S3109, after the camera control circuit A 101 sends the 1-byte start address information data, it outputs SCL and maintains it for one clock, and confirms the signal level of SDA. When the signal level of SDA is low, it is determined as the data reception notification (ACK) from the accessory control circuit 201, and the process proceeds to S3110. On the other hand, when the signal level of SDA is high, it is determined that the accessory control circuit 201 has not received the data normally, and the process proceeds to S3122.

[0139] In S3110, similar to S3102, the camera control circuit A 101 changes SDA to low while SCL is at a high level, and notifies the accessory control circuit 201 of the start condition.

[0140] In S3111, the camera control circuit A 101 sets the slave address information indicating the slave address of the accessory control circuit 201 to the high 7 bits of the data to be transmitted. In this embodiment, it is assumed that the slave address of the accessory control circuit 201 is 1010000 in binary.

[0141] In S3112, the camera control circuit A 101 sets the information indicating read communication to the low 1 bit of the data to be transmitted. Setting this bit to 1 means read communication.

[0142] In S3113, the camera control circuit A 101 sends the data set as the data to be transmitted in S3003 and S3004 (10100001 in binary and 0xA1 in hexadecimal) to the accessory control circuit 201.

[0143] In S3114, after the camera control circuit A 101 sends 1-byte data, it outputs SCL and maintains it for one clock, and confirms the signal level of SDA. When the signal level of SDA is low, it is determined as the data reception notification (ACK) from the accessory control circuit 201, and the process proceeds to S3115. On the other hand, when the signal level of SDA is high, it is determined that the accessory control circuit 201 has not received the data normally, and the process proceeds to S3122.

[0144] In S3115, the camera control circuit A 101 stores 1 in the internal variable M. The internal variable M is a variable used to count the number of received data.

[0145] In S3116, the camera control circuit A 101 outputs 1 byte of SCL and reads the signal level of SDA at the timing when SCL changes from low level to high level. This configuration enables the reception of 1 byte of data from the accessory control circuit 201. The received 1 byte of data can be stored as data corresponding to address 0x00 in the volatile memory 125 or used for predetermined processing.

[0146] In S3117, the camera control circuit A 101 determines whether 1 byte of data has been normally received. In the case of normal reception, the process proceeds to S3118. In the case of no normal reception, the process proceeds to S3119.

[0147] In S3118, the camera control circuit A 101 confirms whether the internal variable M has the same value as the value of the internal variable N. If the internal variable M has the same value as the value of the internal variable N, it is determined that the reception of all data is completed, and the process proceeds to S3119. If the internal variable M does not have the same value as the value of the internal variable N, it is determined that there is still data to be received, and the process proceeds to S3120.

[0148] In S3120, the camera control circuit A 101 provides a data reception notification (ACK) to the accessory control circuit 201 and notifies the accessory control circuit 201 of continuous data communication by outputting 1 byte of SCL and by performing control to change SDA to low level.

[0149] In S3121, the camera control circuit A 101 increments the internal variable M by 1, and the process returns to S3116.

[0150] Therefore, after the process returns to S3116, the camera control circuit A 101 sequentially increments the address of the data to be received and receives 1 byte of data corresponding to each address. In this way, the camera control circuit A 101 receives N bytes of data from the accessory control circuit 201 by repeating the reception of 1 byte of data until the internal variable M and the internal variable N have the same value in the process of S3118. In the case where the internal variable N is set to 3 as in this embodiment, 3 bytes of data can be received.

[0151] In S3119, the camera control circuit A 101 outputs 1 byte of SCL and performs control to change SDA to high level to notify the accessory control circuit 201 of the completion of data communication (NACK).

[0152] In S3122, the camera control circuit A 101 changes SDA to high level (stop condition) while SCL is at high level. Thereby, the communication end is notified to the accessory control circuit 201.

[0153] Figure 18A and Figure 18B The flowchart in it illustrates the processing to be performed by the accessory control circuit 201 when the camera control circuit A 101 sends N-byte data to the accessory control circuit 201 and when the camera control circuit A 101 receives N-byte data from the accessory control circuit 201.

[0154] In S3201, the accessory control circuit 201 waits for SDA to change to low level (start condition) while SCL is at high level. When the accessory control circuit 201 detects the start condition, the process proceeds to S3202.

[0155] In S3202, the accessory control circuit 201 stores 0 in the internal variable M. The internal variable M is a variable used to count the number of transmitted data and the number of received data.

[0156] In S3203, the accessory control circuit 201 receives 1-byte data sent from the camera control circuit A 101.

[0157] In S3204, the accessory control circuit 201 determines whether the high 7-bit data of the 1-byte data received in S3203 is the same as the slave address of the accessory control circuit 201 (0x50 in this embodiment). If the address is the same as the slave address of the accessory control circuit 201, the process proceeds to S3205. If the address is not the same as the slave address of the accessory control circuit 201, the process proceeds to S3221.

[0158] In S3205, the accessory control circuit 201 provides a data reception notification (ACK) to the camera control circuit A 101 by controlling to change SDA to low level for the next SCL clock output after receiving the 1-byte data.

[0159] In S3206, the accessory control circuit 201 determines the type of data for the next 1-byte communication based on the low 1-bit data of the 1-byte data received in S3203. If the low 1-bit data is 0, it is determined that the data for the next 1-byte communication is the start address information from the camera control circuit A 101 to the accessory control circuit 201, and the process proceeds to S3207. If the low 1-bit data is 1, it is determined that the data for the next 1-byte communication is the data sent from the accessory control circuit 201 to the camera control circuit A 101, and the process proceeds to S3209.

[0160] In S3207, the accessory control circuit 201 receives 1-byte data sent from the camera control circuit A 101. The received 1-byte data is information indicating the address of the data to be transmitted and received in subsequent communications. In the present embodiment, as described with reference to Figure 16 and Figure 17 , it is assumed that the start address information is 0x00.

[0161] On the other hand, in S3209, the accessory control circuit 201 uses the address information pre-stored in the accessory control circuit 201 or the address information notified in advance from the camera control circuit A 101 as the start address information.

[0162] In S3208, when the accessory control circuit 201 determines that the 1-byte data can be normally received, the process proceeds to S3210. When it is determined that the 1-byte data cannot be normally received, the process proceeds to S3221.

[0163] In S3210, the accessory control circuit 201 provides a data reception notification (ACK) to the camera control circuit A 101 by controlling to change SDA to a low level for the next SCL clock output after receiving the 1-byte data.

[0164] In S3211, the accessory control circuit 201 confirms whether SDA changes to a low level (start condition) while SCL is at a high level. When the accessory control circuit 201 detects the start condition, the accessory control circuit 201 determines that the next 1-byte data to be communicated is data representing the slave device address and communication type to be sent from the camera control circuit A 101 to the accessory control circuit 201. Then, the process proceeds to S3212. When the accessory control circuit 201 does not detect the start condition, the accessory control circuit 201 determines that the next 1-byte data to be communicated is the data information received by the accessory control circuit 201 from the camera control circuit A 101. Then, the process proceeds to S3216.

[0165] In S3212, the accessory control circuit 201 receives 1-byte data sent from the camera control circuit A 101.

[0166] In S3213, the accessory control circuit 201 determines whether the high 7-bit data of the 1-byte data received in S3212 is consistent with the slave device address of the accessory control circuit 201 (0x50 in the present embodiment). When the high 7-bit data is consistent with the slave device address of the accessory control circuit 201, the process proceeds to S3214. When the high 7-bit data is not consistent with the slave device address of the accessory control circuit 201, the process proceeds to S3221.

[0167] In S3214, the accessory control circuit 201 determines the data type to be used for the next 1-byte communication based on the lower 1-bit data of the 1-byte data received in S3203. If the lower 1-bit data is 0, the process proceeds to S3221. If the lower 1-bit data is 1, it is determined that the data for the next 1-byte communication is data to be sent from the accessory control circuit 201 to the camera control circuit A101, and the process proceeds to S3215.

[0168] In S3215, the accessory control circuit 201 provides a data reception notification (ACK) to the camera control circuit A101 by controlling to change SDA to a low level for the next SCL clock output after receiving 1-byte data.

[0169] In S3222, the accessory control circuit 201 sends 1-byte data corresponding to the start address information received from the camera control circuit A101 in S3207 or the start address information determined in S3209 to the camera control circuit A101.

[0170] In S3223, the accessory control circuit 201 increments the internal variable M by 1, and the process proceeds to S3224.

[0171] In S3224, after sending 1-byte data, the accessory control circuit 201 confirms the signal level of SDA. If the signal level of SDA is high, the camera control circuit A101 determines that this is a notification (NACK) of receiving all data, and the process proceeds to S3225. On the other hand, if the signal level of SDA is low, it is determined that the camera control circuit A101 continues to request data transmission from the accessory control circuit 201, and the process returns to S3222. Therefore, after the process returns to S3222, the accessory control circuit 201 sequentially increments the address of the data to be sent and sends 1-byte data corresponding to each address. Thus, by repeatedly sending 1-byte data from the camera control circuit A101 until NACK is notified in the process of S3224, the accessory control circuit 201 sends N-byte data to the camera control circuit A101.

[0172] In S3225, the accessory control circuit 201 waits for a stop condition under which SDA changes to a high level while SCL is at a high level. When the accessory control circuit 201 detects the stop condition, the communication is terminated.

[0173] On the other hand, in S3216, the accessory control circuit 201 receives 1-byte data and stores the 1-byte data in a non-volatile memory (not shown) as data corresponding to the start address information received from the camera control circuit A 101 in S3207, or uses the 1-byte data for a predetermined process.

[0174] In S3217, the accessory control circuit 201 increments the internal variable M by 1, and the process proceeds to S3218.

[0175] In S3218, if the accessory control circuit 201 determines that 1-byte data can be normally received, the process proceeds to S3219. If it is determined that 1-byte data cannot be normally received, the process proceeds to S3221.

[0176] In S3219, the accessory control circuit 201 provides a data reception notification (ACK) to the camera control circuit A 101 by controlling to change SDA to a low level for the next SCL clock output after receiving the 1-byte data.

[0177] In S3230, the accessory control circuit 201 confirms whether it has detected a stop condition in which SDA changes to a high level while SCL is at a high level. When the accessory control circuit 201 detects the stop condition, the accessory control circuit 201 terminates the communication. On the other hand, when the accessory control circuit 201 does not detect the stop condition, the accessory control circuit 201 determines that data will be continuously transmitted from the camera control circuit A 101 to the accessory control circuit 201. Then, the process returns to S3216.

[0178] Therefore, after the process returns to S3216, the accessory control circuit 201 sequentially increments the address of the data to be received and receives 1-byte data corresponding to each address. By repeating the reception of 1-byte data until the stop condition is notified in S3220, the accessory control circuit 201 receives N bytes of data from the camera control circuit A101.

[0179] Therefore, the camera connector 141 includes contacts TC12 for data signals using the I2C communication method, and contacts TC13 for clock signals using the I2C communication method arranged on one side of the contacts TC12 for the data signals (adjacent to each other on one side). The camera connector 141 further includes contacts TC11 for a second input signal, contacts TC10 for an input selection signal using the SPI communication method, contacts TC09 for reception using the SPI communication method, contacts TC08 for transmission using SPI communication, contacts TC07 for a clock signal using the SPI communication method, contacts TC06 for a first input signal, and contacts TC05 for an output signal, and these contacts are arranged on the other side of the contacts TC12 for the data signals (arranged in order starting from adjacent positions on the other side).

[0180] The accessory 200 stores accessory information in a non-volatile memory (not shown). The accessory information is information for enabling the camera 100 to identify the type of the accessory 200 and specifications related to communication and operation (functions) with the accessory 200. Figure 5 Illustrate an example of accessory information. The accessory information is mapped in the memory space at addresses 0x00 to 0x0F, and the accessory information can be read out from the accessory 200 through I2C communication. Details of the accessory information will be described below. In the I2C communication according to the present embodiment, a checksum value for the read data is added as the final data of the communication.

[0181] Connected to Figure 1 The FNC1 signal connected to TC14 shown as a communication contact, the FNC2 signal connected to TC15, the FNC3 signal connected to TC16, and the FNC4 signal connected to TC17 are function signals whose functions are variable according to the type of the attached accessory 200. For example, when the accessory 200 is a microphone device, the signal communicated via TC15 is a signal related to voice data, and when the accessory 200 is a flash device, the signal communicated via TC14 is a signal notifying the light emission timing.

[0182] Signals for realizing different functions can be communicated via the same contacts according to the type of the attached accessory. For example, when the accessory 200 is an accessory other than a lighting device, a synchronization signal for controlling a timing different from the light emission timing can be communicated via TC14. TC14 to TC17 correspond to function signal contacts. Communication using at least one of the function signal contacts will also be referred to as function signal communication. Function signal communication can be executed at a timing independent of I2C communication and SPI communication in parallel with I2C communication and SPI communication.

[0183] As used herein, the accessory types mean the above-mentioned microphone devices, lighting devices, etc. Accessories that achieve the same purpose (such as lighting with different performances) belong to the same type of accessories. Accessories that achieve different purposes (such as microphone devices and lighting devices) are different types of accessories. Function signal communication is performed based on the information obtained through I2C communication or SPI communication. TC18, as the second ground contact, is also connected to GND and, similar to TC04, is a contact used as the reference potential for the camera 100 and the accessory 200. The differential signal D2N connected to TC19 and the differential signal D2P connected to TC20 are data communication signals for which the two perform data communication in pairs and are connected to the camera control circuit B102. For example, USB communication can be performed via TC19 and TC20.

[0184] TC21 is connected to GND and can be used not only as a reference potential contact but also as a contact for controlling the wiring impedance of the differential signals D2N and D2P. TC21 corresponds to the fourth ground contact. The contacts TC01, TC04, TC06, TC18, and TC21 are connected to the GND portion of, for example, a flexible printed circuit (FPC) board, and the GND portion of the FPC board is fixed to a metal member serving as the GND level of the camera 100 by screws or the like. The metal member serving as the GND level includes, for example, an engagement member that can be engaged with the accessory 200 in the accessory socket portion, and a bottom plate (not shown) inside the camera 100.

[0185] In this embodiment, the attachment detection contact TC06 to which the accessory attachment detection signal / ACC_DET is connected is arranged adjacent to the contact (the first clock contact) TC07 that transmits the clock signal SCLK (the first clock signal). Generally, noise (clock noise) associated with potential fluctuations of the clock signal is transmitted to the contact adjacent to the contact of the clock signal, which may cause malfunctions. In particular, as in this embodiment, this effect is significant in a configuration with many contacts and a short distance between the contacts. Therefore, by arranging the attachment detection contact TC06 adjacent to the SCLK contact TC07, the influence of clock noise can be suppressed.

[0186] The accessory attachment detection signal / ACC_DET is pulled up before the accessory is attached but is set to the GND potential after the accessory is attached. On the other hand, before the accessory is attached, since the SCLK contact TC07 for transmitting the clock signal does not transmit the clock signal, the potential does not fluctuate. Only after the accessory is attached does the potential fluctuate due to the transmission of the clock signal.

[0187] When the clock signal is transmitted at the SCLK contact TC07, the attachment detection contact TC06 is at the GND potential. Therefore, even if the attachment detection contact TC06 receives clock noise, the potentials of the control circuits of the camera 100 and the accessory 200 are not likely to fluctuate, thereby preventing malfunctions. In addition, it is possible to suppress the clock noise from being transmitted to a position farther than the accessory detection contact TC06. As a result, it is not necessary to provide a GND terminal, and thus the influence of the clock noise can be suppressed without increasing the number of contacts.

[0188] An SCL (second clock signal) as a clock signal is also transmitted to a contact (second clock contact) TC13. However, the SCLK transmitted to the SCLK contact TC07 has a higher frequency than that of the SCL, and the SCLK contact TC07 generates more clock noise than the SCL contact TC13. Therefore, arranging the attachment detection contact TC06 adjacent to the SCLK contact TC07 rather than adjacent to the SCL contact TC13 is more effective in preventing malfunctions caused by clock noise.

[0189] In addition to the difference in frequency, the SCL transmitted by the SCL contact TC13 is a clock signal of the I2C communication standard, and the voltage fluctuation of the signal line is driven by an open-drain connection. On the other hand, the SCLK transmitted by the SCLK contact TC07 is a clock signal of the SPI communication standard, and the voltage fluctuation of the signal line is driven by a CMOS output. Therefore, compared with the edge of the voltage fluctuation of the SCLK contact TC07, the edge of the voltage fluctuation of the SCL contact TC13 tends to be smoother and clock noise is less likely to occur. Therefore, arranging the attachment detection contact TC06 adjacent to the SCLK contact TC07 rather than adjacent to the SCL contact TC13 is more effective in preventing malfunctions caused by clock noise.

[0190] Differential signals D1N and D1P can be transmitted in pairs to the first differential signal contact TC19 and the second differential signal contact TC20 to transmit a clock signal. In this case, a clock signal (third clock signal) having a higher frequency than the frequencies of the SCLK contact TC07 and the SCL contact TC13 can be transmitted. However, since the differential signals D1N and D1P are paired signals, the clock noise emission is smaller than the clock noise emission of the SCLK contact TC07 and the SCL contact TC13 that transmit single-ended signals. Therefore, it is more effective to prevent malfunctions caused by clock noise by arranging the attachment detection contact TC06 adjacent to the SCLK contact TC07 rather than adjacent to the first differential signal contact TC19 and the second differential signal contact TC20.

[0191] The contact (first data contact) TC08 arranged on the opposite side of the attachment detection contact TC06 adjacent to the SCLK contact TC07 transmits MOSI (first data signal). Since MOSI is a data signal, MOSI seems to be vulnerable to clock noise. However, MOSI is a data signal of the same SPI communication standard as the clock signal transmitted by the SCLK contact TC07, so the potential fluctuation timing is synchronized with the clock signal and is unlikely to be affected by clock noise. Therefore, the contact TC08 does not have to be fixed to the GND potential and can be used as the MOSI contact.

[0192] The accessory 200 has a battery 205 and receives power supply from the battery 205, and also receives power supply from the camera 100 via the camera connector 141 and the accessory connector 211. The accessory control circuit 201, which is the accessory processing unit in the accessory 200, is a circuit that controls the entire accessory 200 and includes a processor (microcomputer) such as a CPU. The accessory control circuit 201 performs various controls and processes according to a computer program.

[0193] The accessory power supply circuit 202 is a circuit that generates a power supply for supplying power to each circuit in the accessory 200, and includes a DC / DC converter circuit, an LDO, a charge pump circuit, etc. The 1.8V voltage generated by the accessory power supply circuit 202 is constantly supplied to the accessory control circuit 201 as the accessory microcomputer power supply VMCU_A. The voltage generated by the accessory power supply circuit 202 can be different from 1.8V. The control of the accessory power supply circuit 202 can provide on / off control of the power supply to each circuit in the accessory 200.

[0194] The charging circuit 204 is a circuit that charges the battery 205 using the power supplied from the camera 100. When the accessory control circuit 201 can determine that sufficient power has been supplied from the camera 100 for the charging operation, the accessory control circuit 201 controls the charging circuit 204 to charge the battery 205. In this embodiment, the battery 205 is attached to the accessory 200, but the accessory 200 can operate only with the power supply from the camera 100 without the battery 205 attached. In this case, the charging circuit 204 is unnecessary.

[0195] The differential communication circuit 207 is a circuit for differential communication with the camera 100 and can communicate data with the camera 100. The external communication IF circuit 208 is an IF circuit for data communication with an external device (not shown), such as an Ethernet communication IF, a wireless LAN communication IF, and a public network communication IF. The accessory control circuit 201 controls the differential communication circuit 207 and the external communication IF circuit 208 to send the data received from the camera 100 to the external device and send the data received from the external device to the camera 100.

[0196] The functional circuit 206 is a circuit that has different functions according to the type of the accessory 200. When the accessory 200 is a flash device, the functional circuit 206 is, for example, a light-emitting circuit or a charging circuit. When the accessory 200 is a microphone device, the accessory 200 is a voice codec circuit or a microphone circuit.

[0197] The external connection terminal 209 is a connector terminal for connection to an external device and is a USB TYPE-C connector in this embodiment. The connection detection circuit 210 is a circuit for detecting that an external device has been connected to the external connection terminal 209. The accessory control circuit 201 can detect the connection of the external device to the external connection terminal 209 by receiving the output signal of the connection detection circuit 210.

[0198] The power switch 203 is a switch that can be operated by the user to turn on and off the power of the accessory 200 (i.e., the operation). The accessory control circuit 201 can detect the on position and the off position by reading the signal level of the terminal to which the power switch 203 is connected.

[0199] The operation switch 212 is a switch that can be operated by the user to give various instructions to the accessory 200 and perform various settings, and includes a button, a cross key, a slide switch, a dial switch, and a touch sensor. When the operation switch 212 is operated, the accessory control circuit 201 detects the operation and executes a predetermined process according to the operation.

[0200] The accessory connector 211 is a connector that can be electrically connected to the camera 100 via 21 contacts TA01 to TA21 arranged in a row. The contacts TA01 to TA21 are arranged in the order of contacts TA01 to TA21 from one end to the other end in the arrangement direction.

[0201] TA01 is connected to GND and is used not only as a reference potential contact but also as a contact for controlling the wiring impedance of the differential signals D1N and D1P. TA01 corresponds to the third ground contact.

[0202] The differential signal D1N connected to TA02 and the differential signal D1P connected to TA03 are data communication signals for the two to perform data communication in pairs, and are connected to the differential communication circuit 207. TA02, TA03, TA07 to TA10, TA12 to TA17, TA19, and TA20 described below are communication contacts.

[0203] TA04, which is the first ground contact, is connected to GND and serves as the reference potential contact for the camera 100 and the accessory 200. TA04 is arranged outside TA05 described below along the arrangement direction of the contacts.

[0204] The accessory power circuit 202 and the charging circuit 204 are connected to TA05, which is a power contact, and the accessory power VACC supplied from the camera 100 is connected to TA05.

[0205] TA06, which is an attachment detection contact, is directly connected to GND. When the accessory 200 is attached to the camera 100, the accessory control circuit 201 sets the above-mentioned accessory attachment detection signal / ACC_DET to a low level (GND potential) as the activation potential. Thus, the camera 100 can detect the attachment of the accessory 200.

[0206] SCLK connected to TA07, which is a communication contact, MOSI connected to TA08, MISO connected to TA09, and CS connected to TA10 are signals for the accessory control circuit 201 to be used as a communication slave device for SPI communication.

[0207] The communication request signal / WAKE for requesting communication from the accessory control circuit 201 to the camera 100 is connected to TA11, which is a signal contact (communication request contact). When the accessory control circuit 201 determines that communication with the camera 100 is required, the accessory control circuit 201 requests communication with the camera 100 by changing the communication request signal / WAKE from a high level to a low level.

[0208] When power is supplied to the accessory 200 from the camera control circuit 101 via TC5 in response to detecting the attachment of the accessory 200, the accessory control circuit 201 notifies the camera control circuit 101 of receiving the power supply by changing the signal level (by changing the potential of the communication request signal / WAKE) of the communication request signal / WAKE from a high level to a low level.

[0209] Even when there is no request from the camera, the accessory control circuit 201 can notify the presence of a factor that enables the accessory 200 to communicate with the camera 100 by changing the signal level (potential) of the communication request signal / WAKE from high level to low level. With this configuration, the camera control circuit 101 can omit the operation of periodically checking by polling whether the accessory 200 has a factor that requires communication. When a communication required factor occurs, the accessory 200 can communicate with the camera 100 in real time.

[0210] SDA connected to TA12 as a communication contact and SCL connected to TA13 are signals for the accessory control circuit 201 to be used as a communication slave device for I2C communication.

[0211] Therefore, the accessory connector 211 includes a contact TA12 for data signals by the I2C communication method, and a contact TA13 for clock signals by the I2C communication method arranged on one side of the contact TA12 for data signals (adjacent to the contact TA12 for data signals on one side). The accessory connector 211 also includes a contact TA11 for a second input signal, a contact TA10 for an input selection signal by the SPI communication method, a contact TA09 for transmission by the SPI communication method, a contact TA08 for reception by the SPI communication method, a contact TA07 for a clock signal by the SPI communication method, a contact TA06 for a first input signal, and a contact TA06 for an output signal in sequence from a position adjacent to the contact TA12 for data signals on the other side (on the other side).

[0212] The FNC1 signal connected to TA14 as a communication contact (function signal contact), the FNC2 signal connected to TA15, the FNC3 signal connected to TA16, and the FNC4 signal connected to TA17 are function signals whose functions are variable according to the type of the accessory 200. For example, when the accessory 200 is a microphone device, these signals can be signals related to voice data, and when the accessory 200 is a flash device, these signals can be signals for notifying the light emission timing.

[0213] TA18 as a second ground contact is also connected to GND, and similar to TA04, is a reference potential contact for the camera 100 and the accessory 200. The differential signal D2N connected to TA19 and the differential signal D2P connected to TA20 are data communication signals for the two to perform data communication in pairs, and are connected to the external connection terminal 209.

[0214] TA21 is connected to GND and can be used not only as a reference potential contact but also as a terminal for controlling the wiring impedance of differential signals D2N and D2P. TA21 corresponds to the fourth ground contact.

[0215] Contacts TA01, TA04, TA06, TA18, and TA21 are connected to the GND portion of, for example, an FPC substrate, and the GND portion of the FPC substrate is fixed to a metal member serving as the GND level of the accessory 200 using screws (not shown). The metal member serving as the GND level includes, for example, socket attachment legs that can be engaged with the accessory socket portion of the camera 100, and a bottom plate (not shown) inside the accessory 200.

[0216] Figure 6 An example of the processing sequence to be performed when the accessory 200 is attached to the camera 100 is illustrated. Now, the general outlines of the processing of the camera 100 (camera control circuits A 101 and B 102) and the accessory 200 (accessory control circuit 201) will be described, and the details will be described below.

[0217] When the accessory 200 is attached to the camera 100, the accessory attachment detection signal / ACC_DET becomes low. Thereby, the camera control circuit A 101 determines that the accessory 200 is attached to the camera 100. The camera control circuit A 101 that determines that the accessory 200 has been attached sets the power control signal CNT_VACC1 to high level to turn on the output of the accessory power circuit A 131. When the power control signal CNT_VACC1 becomes high, the accessory power circuit A 131 outputs the accessory power VACC.

[0218] The accessory power circuit 202 that has received VACC generates the power VMCU_A used by the accessory control circuit 201. Thereby, the accessory control circuit 201 starts. The started accessory control circuit 201 initializes each block in the accessory 200. After that, when the accessory control circuit 201 is ready to communicate with the camera 100, the accessory control circuit 201 sets the communication request signal / WAKE to low level.

[0219] When the communication request signal / WAKE becomes low, the camera control circuit A 101 detects that the accessory 200 is in a communicable state. The camera control circuit A 101 requests the accessory 200 to communicate accessory information through I2C communication. The accessory control circuit 201 that has received the accessory information request sends the accessory information to the camera control circuit A 101. The accessory control circuit 201 that has sent the accessory information sets the communication request signal / WAKE to high level.

[0220] The camera control circuit A 101 determines whether the attached accessory is controllable based on the received accessory information. The camera control circuit A 101 turns on the accessory power supply circuit B 132. Then, the camera control circuit A 101 performs various settings of the camera 100, and when these settings are completed, the camera control circuit A 101 notifies the camera control circuit B 102 of the accessory information.

[0221] Based on the notified accessory information, the camera control circuit B 102 notifies a control command (accessory control communication) to the accessory 200 through SPI communication or performs control corresponding to a function signal (function signal control). That is, the camera control circuit B 102 controls the accessory 200 through SPI communication.

[0222] The accessory control circuit 201 responds to the control command from the camera 100 through SPI communication and operates according to the function signal.

[0223] Now, the Figure 5 shown accessory information will be described. The D7 - D0 data at address 0x00 is information indicating the type of the accessory (hereinafter referred to as accessory type information). Figure 7 Examples of the accessory type information are illustrated. For example, 0x81 represents a flash device, 0x82 represents an interface conversion adapter device, 0x83 represents a microphone device, and 0x84 represents a multi - accessory connection adapter device for attaching multiple accessory devices to the camera 100.

[0224] The adapter device is an intermediate accessory attached between the camera 100 and accessories such as a flash device and a microphone device. The interface conversion adapter device is an adapter device that converts the interface to provide compatibility between the camera 100 and the accessory when the interfaces of the camera 100 and the accessory are different. The multi - accessory connection adapter device is an adapter device to which multiple accessories can be attached.

[0225] Figure 5 The D7 - D0 data at address 0x01 in [[ ]] is information indicating the model (type) of the accessory 200. The type and model of the accessory can be identified by the above - mentioned accessory type information and this information.

[0226] The D7 - D0 data at address 0x02 is information indicating the firmware version of the accessory 200.

[0227] The D7-D6 data at address 0x03 is specification information indicating whether to request the supply of the accessory power VACC to the accessory 200 when the power switch (not shown) of the camera 100 is turned off. When this information is 0, power supply is not requested. When this information is 1, the accessory power supply circuit A 131 requests power supply. When this information is 2, the accessory power supply circuit B 132 requests power supply.

[0228] The D5-D4 data at address 0x03 is specification information (hereinafter referred to as auto power-off power supply required / not required information) indicating whether to request the supply of the accessory power VACC to the accessory 200 when the camera 100 is in the power saving state (hereinafter referred to as the auto power-off state) through the auto power-off function. The camera 100 has an auto power-off function to save power, and this auto power-off function automatically cuts off the power when the non-operation state without operation continues for a predetermined time. When this information is 0, it means that power supply is not required. When this information is 1, it means that there is a power supply request from the accessory power supply circuit A131. When this information is 2, it means that there is a power supply request from the accessory power supply circuit B 132.

[0229] The D3-D2 data at address 0x03 is specification information indicating whether the accessory 200 has the battery 205. When this information is 0, it means that the accessory 200 does not have a battery, and when this information is 1, it means that the accessory 200 has a battery.

[0230] The D1-D0 data at address 0x03 is specification information indicating whether the accessory 200 has a charging function for the battery 205. When this information is 0, it means that the accessory 200 does not have a charging function, and when this information is 1, it means that the accessory 200 has a charging function.

[0231] The D7-D0 data at address 0x04 is specification information indicating the required power of the accessory power VACC supplied from the camera 100 to the accessory 200. For example, the value obtained by multiplying this information by 10 represents the current value. When this information is 10, it means 100 mA, and when this information is 100, it means 1 A. To reduce the amount of information of this information, this information can be simply associated with the current value. For example, when this information is 0, it can mean 100 mA, when this information is 1, it can mean 300 mA, when this information is 3, it can mean 450 mA, and when this information is 4, it can mean 600 mA.

[0232] The D7 data at address 0x05 is specification information indicating whether the accessory 200 is in the firmware update mode. When this information is 0, it means that the accessory 200 is not in the firmware update mode, and when this information is 1, it means that the accessory 200 is in the firmware update mode.

[0233] The D6 data at address 0x05 is specification information indicating whether the accessory 200 has the firmware update function. When this information is 0, it means that the accessory 200 does not have the firmware update function. When this information is 1, it means that the accessory 200 has the firmware update function.

[0234] The D5 - D4 data at address 0x05 is specification information indicating whether the operation of the accessory 200 attached to the intermediate (connection) accessory is permitted. When this information is 0, it means that the operation is not permitted, and when this information is 1, it means that the operation is permitted.

[0235] The D3 - D2 data at address 0x05 is specification information indicating whether the accessory 200 needs the camera 100 to confirm the connection of the intermediate accessory when the camera 100 is started. When this information is 0, it means that the confirmation is unnecessary, and when this information is 1, it means that the confirmation is necessary.

[0236] The D1 - D0 data at address 0x05 is specification information indicating whether the accessory 200 supports command notification via I2C communication. When this information is 0, it means that command notification is not supported, and when this information is 1, it means that command notification is supported.

[0237] The D5 - D4 data at address 0x06 is specification information indicating the communication request factor acquisition method (the communication method used: hereinafter referred to as the factor acquisition method) of the following communication method, which can be used to notify the camera 100 of the generation factor of the communication request after the accessory 200 notifies the communication request signal / WAKE to the camera 100. When this information is 0, it means that the I2C communication method is the factor acquisition method. When this information is 1, it means that the SPI communication method is the factor acquisition method. When this information is 2, it means that both the I2C communication method and the SPI communication method are the factor acquisition methods.

[0238] The D3-D0 data at address 0x06 is specification information indicating whether the accessory 200 has functions corresponding to the FNC1 signal (function signal 1), FNC2 signal (function signal 2), FNC3 signal (function signal 3), and FNC4 signal (function signal 4). The D0 data corresponds to the FNC1 signal, the D1 data corresponds to the FNC2 signal, the D2 data corresponds to the FNC3 signal, and the D3 data corresponds to the FNC4 signal. When the value is 0, it means the accessory 200 does not have this function. When the value is 1, the accessory 200 has this function.

[0239] The D7 data at address 0x0A is specification information indicating whether the accessory 200 requests the camera 100 to start when the accessory 200 notifies the camera 100 of a communication request signal / WAKE. When this information is 0, it means a start request, and when this information is 1, it means no start request.

[0240] The D6-D0 data at address 0x0A is information indicating the generation factor of the communication request signal / WAKE notified by the accessory 200 to the camera 100.

[0241] Figure 8 Examples of factors (hereinafter also referred to as communication request factors) for generating the communication request signal / WAKE are illustrated. Here, an example in the case where the accessory 200 is a microphone device is shown. For example, the factor number 0x00 is the number indicating that the menu call switch in the operation switch 212 has been operated (pressed). The factor number 0x01 is the number indicating that the accessory 200 has completed the output control of the audio signal. The factor number 0x02 is the number indicating that the accessory 200 has completed the mute processing (unmute) of the audio signal. As described above, in the present embodiment, the information related to the communication request factor (number) used as information related to the generation factor of the communication request signal / WAKE can be notified (sent) from the accessory 200 to the camera 100 as accessory information.

[0242] In Figure 5 the D1 data at address 0x0C is specification information indicating the SPI communication protocol supported by the accessory 200. When this information is 0, it means the accessory 200 supports SPI protocol A, and when this information is 1, it means the accessory 200 supports SPI protocol B.

[0243] The D0 data at address 0x0C is specification information indicating the CS control logic of the SPI communication supported by the accessory 200. When this information is 0, it means CS is low-active logic, and when this information is 1, it means CS is high-active logic.

[0244] The data of D7 - D0 at address 0x0D is specification information representing the time required as a communication byte interval in the case where the accessory 200 communicates according to SPI protocol A and the D7 data at address 0x05 is 0, or the accessory 200 is not in the firmware update mode.

[0245] The data of D7 - D0 at address 0x0E is specification information representing the time required as a communication byte interval in the case where the accessory 200 communicates according to SPI protocol A and the D7 data at address 0x05 is 1, or the accessory 200 is in the firmware update mode.

[0246] Figure 9A and Figure 9B Illustrate the time (communication interval) of the communication byte interval corresponding to the data (0 to 7) at addresses 0x0D and 0x0E. Figure 9A Illustrate the communication interval for the data at address 0x0D, and Figure 9B Illustrate the communication interval for the data at address 0x0E.

[0247] In Figure 5 the data at address 0x0F is data of a checksum value representing the sum of the values at addresses 0x00 to 0x0E.

[0248] Figure 10 Illustrate the startup process that the camera control circuit A 101 has to execute until the accessory 200 is attached to the camera 100 and the functions of the accessory 200 are enabled.

[0249] In S401, the camera control circuit A 101 monitors the signal level of the accessory attachment detection signal (first input signal) / ACC_DET, and judges (detects) whether the accessory 200 is attached. If the signal level of the accessory attachment detection signal / ACC_DET is high, the camera control circuit A 101 judges that the accessory 200 is not attached, and the process returns to S401. Therefore, the camera control circuit A 101 judges again whether the accessory 200 is attached. If the signal level is low, the camera control circuit A 101 judges that the accessory 200 is attached, and the process proceeds to S402.

[0250] In S402, the camera control circuit A 101 performs control to change the power control signal CNT_VACC1 to a high level to turn on the output of the accessory power supply circuit A 131. Then, the process proceeds to S403. When the power control signal CNT_VACC1 is at a high level, the accessory power supply circuit A 131 outputs the accessory power supply (output signal) VACC.

[0251] In S403, the camera control circuit A 101 monitors the signal level of the overcurrent detection signal DET_OVC and determines whether an overcurrent is flowing. If the signal level of DET_OVC is low, the camera control circuit A 101 determines that no overcurrent is flowing, and the process proceeds to S404. If the signal level is high, the camera control circuit A 101 determines that an overcurrent is flowing, and the process proceeds to S405 for error processing.

[0252] In S404, the camera control circuit A 101 monitors the signal level of the communication request signal (second input signal) / WAKE, which is a notification signal from the accessory 200, and determines whether the initialization of the accessory 200 is complete. If the signal level of the communication request signal / WAKE is low (active), the camera control circuit A 101 determines that the initialization is complete, and the process proceeds to S406. If the signal level is high, the camera control circuit A 101 determines that the initialization is not yet complete, and the process returns to S404 so that the camera control circuit A 101 determines again whether the initialization is complete.

[0253] In S406, the camera control circuit A 101 performs I2C communication with the accessory 200 as initial communication and reads 15 bytes of accessory information. Then, the process proceeds to S407.

[0254] In S407, the camera control circuit A 101 determines whether the attached accessory 200 is a compatible device (compatible accessory) with the camera 100 based on the accessory information read in S406. If the camera control circuit A 101 determines that the attached accessory 200 is a compatible accessory, the process proceeds to S408. If the camera control circuit A 101 determines that the attached accessory 200 is not a compatible accessory, the process proceeds to S409 for error processing.

[0255] In S408, the camera control circuit A 101 performs control to change the power control signal CNT_VACC2 to a high level to turn on the output of the accessory power supply circuit B 132. Then, the process proceeds to S410. When the power control signal CNT_VACC2 is at a high level, the accessory power supply circuit B 132 outputs the accessory power VACC. In this embodiment, when both the power control signals CNT_VACC1 and CNT_VACC2 are at a high level, the output from the accessory power supply circuit B 132 is supplied to the accessory power VACC.

[0256] In S410, the camera control circuit A 101 notifies the camera control circuit B 102 of the accessory information read in S406. Thus, the startup process of the camera 100 in response to the attachment of the accessory 200 is completed.

[0257] Figure 11 The flowchart in shows the enabling process that the camera control circuit B 102 has to execute until the accessory 200 is attached to the camera 100 and the functions of the accessory 200 are enabled.

[0258] In S501, the camera control circuit B 102 determines whether accessory information has been notified from the camera control circuit A 101. If the accessory information has not been notified, the process returns to S501, and the camera control circuit B 102 determines again whether the accessory information has been notified. If the accessory information has been notified, the process proceeds to S502.

[0259] In S502, the camera control circuit B 102 sets the function signals FNC1 to FNC4 based on the accessory information notified from the camera control circuit A 101. For example, when it is notified that the accessory 200 is a microphone device, FNC1 is set to be used as the voice data clock signal BCLK, FNC2 is set to be used as the voice data channel signal LRCLK, and FNC3 is set to be used as the voice data signal SDAT. As another example, when it is notified that the accessory 200 is a flash device, FNC4 is set to be used as the flash emission synchronization signal XOUT. For the function signals that do not require control of the accessory 200, a predetermined setting is made so as not to interfere with the operations of the camera 100 and the accessory 200.

[0260] In S503, the camera control circuit B 102 sets the CS control logic in the SPI communication based on the accessory information notified from the camera control circuit A 101.

[0261] In S504, the camera control circuit B 102 determines whether a predetermined event for the accessory 200 has occurred. If the event has not occurred, the process returns to S504, and the camera control circuit B 102 determines again whether the event has occurred. If the event has occurred, the process proceeds to S505.

[0262] In S505, the camera control circuit B 102 determines whether the event determined in S504 is an event that requires SPI communication with the accessory 200. If the event requires SPI communication, the process proceeds to S506, otherwise the process proceeds to S507.

[0263] In S507, the camera control circuit B 102 determines whether the event determined in S504 is an event that requires control of the accessory 200 using a function signal. If the event requires control using a function signal, the process proceeds to S508; otherwise, the process proceeds to S509.

[0264] In S506, the camera control circuit B 102 performs SPI communication with the accessory 200. When the accessory 200 is a microphone device, the SPI communication performed here includes, for example, communication for an instruction to turn on the microphone operation, communication for an instruction to turn off the microphone operation, communication for an instruction to switch the sound collection directionality of the microphone, and communication for an instruction to switch the equalizer function of the microphone. When the accessory 200 is a flash device, the SPI communication includes communication for reading out setting information related to the flash device and communication for notifying the flash device of the setting information. When the SPI communication in S506 is completed, the process returns to S504, and the camera control circuit B 102 determines again whether an event has occurred.

[0265] In S508, the camera control circuit B 102 controls the accessory 200 using a function signal. For example, when the accessory 200 is a microphone device, the camera control circuit B 102 outputs the audio data clock signal BCLK of FNC1 and the audio data channel signal LRCLK of FNC2, and receives the audio data signal SDAT of FNC3. Thus, the camera 100 can acquire voice data from the microphone device. When the accessory 200 is a flash device, the camera control circuit B 102 outputs the flash emission synchronization signal XOUT of FNC4 at a predetermined timing. Thus, the camera 100 can instruct the flash device to emit light. When the control using the function signal is completed in this way, the process returns to S504, and the camera control circuit B 102 determines again whether an event has occurred.

[0266] In S509, the camera control circuit B 102 performs predetermined in-camera control according to the event determined in S504. When the accessory 200 is a microphone device, the in-camera control includes, for example, control for starting or ending the recording of voice data in the recording memory 126 and control for performing equalizer processing on the voice data. When the accessory 200 is a flash device, the in-camera control includes photometric control for using the image sensor 122 to accumulate and acquire the light emitted by the flash device and control for calculating an indication value of the light emission amount of the flash device. When the in-camera control is completed in this way, the process returns to S504, and the camera control circuit B 102 determines again whether an event has occurred.

[0267] By the above-described start-up process using the camera control circuit A 101 and the enabling process using the camera control circuit B 102, the accessory 200 attached to the camera 100 can be controlled.

[0268] Figure 12 The flowchart in [FIGURE] illustrates the processes to be executed by the accessory control circuit 201 from when the accessory 200 is attached to the camera 100 until when various functional operations of the accessory 200 are enabled.

[0269] In S601, the accessory control circuit 201 waits for the accessory power supply VACC from the camera 100 to be turned on. In the case where the accessory 200 does not have the battery 205, when power is supplied to the accessory control circuit 201 and the operation of the accessory control circuit 201 itself starts, the turning on of the accessory power supply VACC can be detected. In the case where the accessory 200 has the battery 205, the accessory control circuit 201 can monitor the voltage value of the accessory power supply VACC to detect the turning on of the accessory power supply VACC.

[0270] In S602, the accessory control circuit 201 performs predetermined initial settings. For example, the accessory control circuit 201 sets the operation frequency of the microcomputer, the input / output control ports of the microcomputer, the initialization of the timer function of the microcomputer, and the initialization of the interrupt function of the microcomputer.

[0271] When the initial settings in S602 are completed, in S603, the accessory control circuit 201 performs control for changing the communication request signal / WAKE to a low level. Thereby, the camera 100 is notified that the initial settings are completed.

[0272] In S604, the accessory control circuit 201 responds to the I2C communication from the camera 100 and transmits 15-byte accessory information to the camera 100 as initial communication. The accessory information includes Figure 5 the various information shown.

[0273] When the initial communication in S604 is completed, in S605, the accessory control circuit 201 controls the communication request signal / WAKE to a high level.

[0274] In S606, the accessory control circuit 201 determines whether a predetermined event has occurred. If no event has occurred, the process returns to S606, and the accessory control circuit 201 determines again whether an event has occurred, and if an event has occurred, the process proceeds to S607.

[0275] In S607, the accessory control circuit 201 determines whether the event determined in S606 is an event that requires SPI communication with the camera 100. If the event requires SPI communication, the process proceeds to S608; otherwise, the process proceeds to S609.

[0276] In S609, the accessory control circuit 201 determines whether the event determined in S606 is an event that requires I2C communication with the camera 100. If the event requires I2C communication, the process proceeds to S610; otherwise, the process proceeds to S611.

[0277] In S611, the accessory control circuit 201 determines whether the event determined in S606 is an event that requires control using a function signal. If the event requires control using a function signal, the process proceeds to S612; otherwise, the process proceeds to S613.

[0278] In S613, the accessory control circuit 201 determines whether the event determined in S606 is an event that requires notification to the camera 100 via a communication request signal / WAKE. If the event requires notification to the camera 100 via a communication request signal / WAKE, the process proceeds to S614; otherwise, the process proceeds to S615.

[0279] In S608, the accessory control circuit 201 performs SPI communication with the camera 100. When the communication request signal / WAKE is at a low level during the execution of SPI communication by the accessory control circuit 201, the accessory control circuit 201 performs control to change the communication request signal / WAKE to a high level after the SPI communication. When the accessory 200 is a microphone device, the SPI communication performed here includes, for example, communication for an instruction to turn on the microphone operation from the camera 100, communication for an instruction to turn off the microphone operation, and communication for an instruction to switch the sound collection directionality of the microphone. The SPI communication also includes communication for an instruction to switch the equalizer function of the microphone. When the accessory 200 is a flash device, the SPI communication includes communication for reading setting information related to the flash device and communication for notifying the flash device of the setting information. When the predetermined SPI communication in S608 is completed, the process returns to S606, and the accessory control circuit 201 determines again whether an event has occurred.

[0280] In S610, the accessory control circuit 201 performs I2C communication with the camera 100. When the communication request signal / WAKE is at a low level during the execution of I2C communication, control is performed to change the communication request signal / WAKE to a high level after the I2C communication. The I2C communication performed here includes, for example, communication for reading out the communication request factor of the communication request signal / WAKE that the accessory control circuit 201 has notified the camera 100. When the I2C communication in S610 is completed, the process returns to S606, and the accessory control circuit 201 determines again whether an event has occurred.

[0281] In S612, the accessory control circuit 201 controls the camera 100 using function signals. When the accessory 200 is a microphone device, the control performed here includes, for example, reception control of the audio data clock signal BCLK of FNC1 and the audio data channel signal LRCLK of FNC2 output from the camera 100. This control also includes output control of the voice data signal SDAT of FNC3 synchronized with these signals. When the accessory 200 is a flash device, this control includes reception control of the flash emission synchronization signal XOUT of FNC4 and corresponding flash emission control. When the control using function signals in S612 is completed, the process returns to S606, and the accessory control circuit 201 determines again whether an event has occurred.

[0282] In S614, the accessory control circuit 201 stores the communication request factor number to the camera 100 in response to the event determined in S606 in a volatile memory (not shown) of the accessory 200, and performs control to change the communication request signal / WAKE to a low level. As Figure 8 shown, the communication request factor number is a unique number assigned to each factor content. When the low-level control of the communication request signal / WAKE in S614 is completed, the process returns to S606, and the accessory control circuit 201 determines again whether an event has occurred.

[0283] In S615, the accessory control circuit 201 performs in-accessory control according to the event determined in S606. When the accessory 200 includes a battery 205, the in-accessory control performed here includes control for detecting the remaining battery level, and control for detecting the operation of the operation switch 212, etc. When the in-accessory control in S615 is completed, the process returns to S606, and the accessory control circuit 201 determines again whether an event has occurred.

[0284] Through the above processing using the accessory control circuit 201, after the accessory 200 is attached to the camera 100, the accessory 200 can perform various functional operations.

[0285] Figure 13 Example Figure 6 Figure 6 The processing to be performed by the camera control circuits A 101 and B 102 when the accessory 200 is attached to the camera 100 before the camera 100 is powered on in the processing sequence shown. The description of the processing identical to that of Figure 6 will be omitted.

[0286] The camera control circuit A 101 supplies the camera microcomputer power supply VMCU2_C to the camera control circuit B in parallel with the accessory detection process using the accessory detection signal / ACC_DET, and powers on the camera control circuit B 102. The camera control circuit B 102 performs its own initialization process through power-on, and notifies the camera control circuit A 101 of the completion of preparation when the initialization process is completed.

[0287] The camera control circuit 101A that has received the preparation completion notification notifies the camera control circuit B 102 of the accessory information obtained from the accessory 200.

[0288] Through the above processing, the camera control circuit A 101 can perform the detection process of the attachment of the accessory 200 to the camera 100 and the startup process of the camera control circuit B 102 in parallel. Therefore, the startup time of the accessory 200 (i.e., the imaging system) can be shortened. That is to say, the responsiveness at startup can be improved.

[0289] Second Embodiment

[0290] The second embodiment according to the present invention will be described. Figure 14A and Figure 14B Example Figure 6 Figure 6 The processing to be performed by the camera control circuits A 101 and B 102 when the accessory 200 is attached to the camera 100 in a state where the camera 100 is in the low power consumption mode (sleep mode) in the processing sequence shown. The description of the processing identical to that of Figure 6 will be omitted.

[0291] In Figure 14A Figure 14A , when it is detected that the accessory 200 is attached in the low power consumption mode, the camera control circuit A 101 does not supply power to the Figure 13 camera control circuit B 102 shown, but outputs the power supply for the accessory and obtains the accessory information.

[0292] In Figure 14B Figure 14B , when the low power consumption mode is switched to the normal operation mode in response to the input detection, the camera control circuit A 101 supplies power to the camera control circuit B 102. When the initialization process is completed, the camera control circuit B 102 notifies the camera control circuit A 101 of the completion of preparation.

[0293] The camera control circuit A 101 that has received the preparation completion notification notifies the camera control circuit B 102 of the accessory information obtained in Figure 14A .

[0294] The camera control circuit B 102 that has received the accessory information performs control switching of the accessory based on the accessory information, and performs accessory control communication and function signal control on the accessory 200.

[0295] Through the above processing, when the camera 100 starts from the low power consumption mode, the camera 100 can omit the accessory detection process, and can shorten the start-up time of the accessory 200 (i.e., the imaging system). That is to say, the responsiveness at start-up can be improved.

[0296] Third Embodiment

[0297] Now, the third embodiment according to the present invention will be described. The camera 100 includes a shutter button (not shown), a first shutter switch (hereinafter referred to as SW1) and a second shutter switch (hereinafter referred to as SW2) that are turned on by the operation of the shutter button. SW1 is turned on by a half-press operation of the shutter button, and indicates the start of imaging preparation operations such as automatic exposure control and focus control. SW2 is turned on by a full-press operation of the shutter button, and indicates still image shooting.

[0298] Normally, after SW1 is turned on and then the imaging preparation operation is completed, SW2 is turned on. However, the shutter button can be fully pressed at once so that SW2 is immediately turned on when SW1 is turned on. In this embodiment, the state where the shutter button is fully pressed at once and SW1 and SW2 are turned on almost simultaneously will be referred to as the simultaneous turn-on of SW1 and SW2.

[0299] Figure 19 The flowchart in

[0300] illustrates the processing to be performed by the camera control circuit B 102 in the case of the simultaneous turn-on of SW1 and SW2. Figure 13 or Figure 14A and Figure 14B shown receives the accessory information from the camera control circuit A 101 through the communication exchange shown.

[0301] Next, in S702, the camera control circuit B 102 determines whether SW2 is turned on (i.e., the simultaneous turn-on of SW1 and SW2), and if SW2 is turned on, the process proceeds to step S703.

[0302] In S703, the camera control circuit B 102 refers to the accessory information obtained in S701 and determines whether the accessory 200 is a flash device. If the accessory 200 is a flash device, the process proceeds to S704, and if the accessory 200 is not a flash device, the process proceeds to S707.

[0303] In S704, the camera control circuit B 102 performs SPI communication required for flash photography with the accessory 200. Using this SPI communication, it is also possible to obtain charge completion information indicating whether the charging of the accessory 200 is completed.

[0304] Next, in S705, the camera control circuit B 102 refers to the charge completion information obtained in S704 and determines whether the charging of the accessory 200 is completed. If the charging is completed, the process proceeds to S706, and if the charging is not yet completed, the process proceeds to S707.

[0305] In S706, the camera control circuit B 102 permits flash photography, and the process proceeds to the next S708. If the automatic exposure control and focus control are not yet completed at this time, the camera control circuit B 102 does not permit flash photography and waits for the completion of these two controls.

[0306] In S708, the camera control circuit B 102 performs light amount control on the accessory 200 and determines the flash light emission amount during photography.

[0307] After that, the process proceeds to S709, and the camera control circuit B 102 causes the flash to emit light with the flash light emission amount determined in S708 and performs main photography. Then, this process ends.

[0308] On the other hand, in S707, the camera control circuit B 102 permits non-flash (non-light-emitting) photography, and the process proceeds to S710. If the automatic exposure control or focus control is not yet completed at this time, the camera control circuit B 102 waits for the completion of these two controls without permitting non-flash photography.

[0309] After that, the process proceeds to S710, and the camera control circuit B 102 performs main photography without causing the accessory 200 to emit flash light. Then, this process ends.

[0310] Figure 20 The flowchart in shows the processing according to a comparative example that is different from the processing to be executed by the camera control circuit B 102 when SW1 and SW2 are turned on simultaneously. Figure 19 as shown.

[0311] In S801, the camera control circuit B 102 does not perform the operation related toFigure 19 When the accessory information corresponding to S701 in is received, it is determined whether SW2 is turned on (simultaneous turn-on of SW1 and SW2). If SW2 is turned on, the process proceeds to step S802, and the camera control circuit B 102 communicates with the accessory 200 via SPI in the same manner as in Figure 19 S704 in.

[0312] Next, in S803, the camera control circuit B 102 determines whether the accessory 200 is a fully charged flash device based on the information obtained through the SPI communication in S802. If the accessory 200 is a fully charged flash device, the process proceeds to S804; otherwise, the process proceeds to S805. S804 to S808 are the same as Figure 19 S706 to S710 in respectively.

[0313] In Figure 20 During the process of, the camera control circuit B 102 does not obtain the accessory information from the accessory 200 in advance. Therefore, when SW2 is turned on (S801), the SPI communication with the accessory 200 is always performed (S802).

[0314] However, when the accessory 200 is not a flash device, SPI communication is not required for shooting control. Unnecessary SPI communication will increase the time lag until shooting is permitted. On the other hand, as Figure 19 shown, obtaining the accessory information in advance in S701 enables shooting to be permitted without SPI communication (S704) when an accessory other than the flash device is attached, thereby reducing the time lag.

[0315] Fourth Embodiment

[0316] Now, the fourth embodiment according to the present invention will be described. The camera 100 uses the display circuit 127 for live view display. Generally, the brightness of the live view image is adjusted to be the same as the brightness of the captured image. However, when a flash device is attached as the accessory 200, the brightness of the captured image obtained by flash shooting is unknown before shooting, so the brightness of the live view image is adjusted as follows.

[0317] For example, assume that the user manually sets F4, a shutter speed of 1 / 60 s, and ISO 100 in the camera 100 for a subject to be photographed with appropriate exposure using F4, a shutter speed of 1 / 60 s, and ISO 400. In this case, since the exposure of the photographed image is two stops underexposed, the brightness of the live view image can be set to two stops underexposed. However, when the attached accessory 200 is a fully charged flash unit, the setting of the brightness of the live view image is changed. This is because underexposure may result in appropriate exposure due to the flash light.

[0318] Figure 21 The flowchart in FIG. illustrates the live view display process to be executed by the camera control circuit B 102 when the camera 100 is activated.

[0319] First, in S901, the camera control circuit B 102 receives accessory information from the camera control circuit A 101 through the communication switches shown in FIG. or FIG. Figure 13 or Figure 14A and Figure 14B shown.

[0320] Next, in S902, the camera control circuit B 102 determines whether there is an instruction to display live view (LV). If there is such an instruction, the process proceeds to S903, and if there is no instruction, the camera control circuit B 102 repeats the determination in this step.

[0321] In S903, the camera control circuit B 102 refers to the accessory information obtained in S901 and determines whether the accessory 200 is a flash unit. If the accessory 200 is a flash unit, the process proceeds to S904, and if the accessory 200 is not a flash unit, the process proceeds to S907.

[0322] In S904, the camera control circuit B 102 performs SPI communication with the accessory 200 to obtain charge completion information.

[0323] Next, in S905, the camera control circuit B 102 refers to the charge completion information obtained in S904 and determines whether the charging of the accessory 200 is completed. If the charging is completed, the process proceeds to S906, and if the charging is not completed, the process proceeds to S907.

[0324] In S906, the camera control circuit B 102 sets the brightness of the live view image to the brightness corresponding to appropriate exposure (such as F4, 1 / 60 S, and ISO 400, etc.), and causes the display circuit 127 to display the live view image. Then, the process proceeds to S908.

[0325] On the other hand, in S907, the camera control circuit B 102 sets the brightness of the live view image to the brightness corresponding to the shooting exposure (such as F4, 1 / 60s, and ISO100, etc.), and causes the display circuit 127 to display the live view image. Then, the process proceeds to S908.

[0326] In S908, the camera control circuit B 102 determines whether the photometry timer is counting. If the photometry timer is counting, the process proceeds to S909, and if the photometry timer is not counting, the camera control circuit B 102 repeats the determination in this step. The photometry timer starts counting at the timing when SW1 is turned on and counts for a specified time.

[0327] The processing related to the live view display when the photometry timer is counting (S909 to S913) is the same as the processing related to the live view display before the photometry timer starts counting (S903 to S907). Therefore, unless there is a change in the state of the accessory 200 (such as the charging state, etc.), the brightness of the live view image becomes the same before and after the photometry timer starts counting.

[0328] Figure 22 The flowchart in shows the live view display processing as a comparative example that the camera control circuit B 102 needs to execute when the camera 100 is started, which is different from the processing shown in Figure 21 Shown processing.

[0329] In S1001, the camera control circuit B 102 determines whether there is an instruction for live view (LV) display without performing the receiving process of the accessory information corresponding to S901 in Figure 21 . If there is such an instruction, the process proceeds to S1002, and if there is no instruction, the camera control circuit B 102 repeats the determination in this step.

[0330] In S1002, the camera control circuit B 102 sets the brightness of the live view image to the brightness corresponding to the shooting exposure, and causes the display circuit 127 to display the live view image.

[0331] Next, in S1003, the camera control circuit B 102 determines whether the photometry timer is counting. If the photometry timer is counting, the process proceeds to S1004, and if the photometry timer is not counting, the camera control circuit B 102 repeats the determination in this step.

[0332] In S1004, the camera control circuit B 102 performs SPI communication to obtain information related to the accessory 200 as a flash device. Only when the photometry timer is counting, can the power consumption be reduced through SPI communication.

[0333] Next, in S1005, the camera control circuit B 102 determines whether the accessory 200 is a fully charged flash device based on the information obtained through the SPI communication in S1004. If the accessory 200 is a fully charged flash device, the process proceeds to S1006; otherwise, the process proceeds to S1007.

[0334] In S1006, the camera control circuit B 102 sets the brightness of the live view image to the brightness corresponding to proper exposure and causes the display circuit 127 to display the live view image. Then, this process is terminated.

[0335] On the other hand, in S1007, the camera control circuit B 102 sets the brightness of the live view image to the brightness corresponding to shooting exposure and causes the display circuit 127 to display the live view image. Then, this process is terminated.

[0336] In Figure 22 In the process shown, the camera control circuit B 102 cannot obtain the accessory information in advance. Therefore, the camera control circuit B 102 once displays the live view image at the brightness corresponding to shooting exposure in S1002, and then if the flash device is fully charged, the camera control circuit B 102 switches the brightness of the live view display to the brightness corresponding to proper exposure (S1006). Therefore, the brightness of the live view display changes.

[0337] On the other hand, in Figure 21 In the process shown, the camera control circuit B 102 can obtain the accessory information in advance in S901, and thus can perform control to adjust the brightness of the live view display to the brightness corresponding to the accessory 200 from the start of the live view display (S906, S907). Therefore, the brightness of the live view display does not change.

[0338] In each of the above embodiments, the first communication method is the I2C communication method and the second communication method is the SPI communication method, but the first communication method and the second communication method can be communication methods other than the I2C communication method and the SPI communication method.

[0339] In each of the above embodiments, the electronic device is a photographing device, but the electronic device according to the present invention can include various electronic devices other than the photographing device.

[0340] In each of the above-described embodiments, the accessory 200 is directly attached to the camera 100, but another attachment form may also be used. For example, the camera 100 and the main accessory corresponding to the accessory 200 may communicate with each other via the main accessory and an intermediate accessory (such as an adapter device to which the camera 100 is attached). In this case, the intermediate accessory may perform communication control similar to at least a part of the communication control performed by the accessory 200 and the communication control performed by the camera 100 in the above-described embodiments. The intermediate accessory may serve as an information transmission path such that the accessory outputs information corresponding to the information input from the camera 100 to the main accessory, and the main accessory outputs information corresponding to the input information to the camera 100. Therefore, the accessories according to the embodiments of the present invention include various accessories such as a microphone device, a lighting device, and an adapter device. In addition, the adapter device may also be included in an electronic device.

[0341] Each of the above-described embodiments may provide an electronic device, a control method of the electronic device, an accessory, and a control method of the accessory, each of which may enhance the responsiveness at startup in a system in which the accessory is attached to the electronic device.

[0342] Other embodiments

[0343] Embodiments of the present invention may also be implemented by a method in which software (program) that executes the functions of the above-described embodiments is supplied to a system or device via a network or various storage media, and a computer or a central processing unit (CPU) or a microprocessing unit (MPU) of the system or device reads and executes the program.

[0344] Although the present invention has been described with reference to exemplary embodiments, it should be understood that the present invention is not limited to the disclosed exemplary embodiments. The scope of the appended claims is to be accorded the broadest interpretation so as to encompass all such modifications, equivalent structures, and functions.

Claims

1. An electronic device capable of detachably attaching an accessory, the electronic device comprising: An accessory socket portion to which the accessory can be attached; A first processing unit capable of communicating with the accessory by a first communication method; And A second processing unit capable of communicating with the accessory by a second communication method different from the first communication method, Characterized in that the first processing unit receives accessory information for identifying the accessory from the accessory by the first communication method, Wherein the second processing unit communicates with the accessory for controlling the accessory by the second communication method based on the accessory information, Wherein the electronic device has a first power state and a second power state, the power of the second power state being lower than the power of the first power state, and each of the first power state and the second power state is a state capable of communicating with the accessory, wherein the first processing unit communicates with the accessory by the first communication method in the first power state and the second power state, Wherein the second processing unit communicates with the accessory by the second communication method in the first power state and does not send information to or receive information from the accessory by the second communication method in the second power state, and Wherein the contacts for receiving the accessory information by the first communication method are different from the contacts for communicating for controlling the accessory by the second communication method.

2. The electronic device according to claim 1, wherein The first processing unit includes a processor that operates using less power than the processor that constitutes the second processing unit.

3. The electronic device according to claim 1, wherein The first processing unit and the second processing unit are provided in a single processor.

4. The electronic device according to claim 2, wherein The communication speed of the first communication method is lower than the communication speed of the second communication method.

5. The electronic device according to claim 1, wherein The first processing unit operates in the first power state and the second power state, Wherein the second processing unit does not operate in the second power state and operates in the first power state.

6. The electronic device according to claim 1, wherein Before the second processing unit is ready to communicate with the accessory by the second communication method, the first processing unit, in response to detecting that the accessory is attached to the electronic device, receives accessory information for identifying the accessory from the accessory by the first communication method.

7. The electronic device according to claim 1, wherein When the electronic device is started, the first processing unit starts before the second processing unit, so that the detection of the attachment of the accessory and the start of the second processing unit are performed in parallel, and the accessory information is notified to the started second processing unit.

8. The electronic device according to claim 1, wherein The accessory information includes information related to the type of the accessory and information related to the communication and operation specifications of the accessory.

9. The electronic device according to claim 1, characterized in that, The first processing unit outputs an output signal to the accessory by detecting a first input signal activated by the accessory in response to the accessory being attached to the electronic device, and communicates with the accessory via the first communication method in response to detecting a second input signal activated by the accessory that has received the output signal.

10. The electronic device according to claim 1, characterized in that, The first communication method is an I2C communication method, and the second communication method is an SPI communication method.

11. The electronic device according to claim 10, wherein The first processing unit outputs an output signal to the accessory by detecting a first input signal activated by the accessory in response to the accessory being attached to the electronic device, and communicates with the accessory via the first communication method in response to detecting a second input signal activated by the accessory that has received the output signal. wherein the electronic device includes a plurality of contacts arranged in a row, the plurality of contacts being capable of being electrically connected to a plurality of contacts arranged in a row in the accessory, and wherein the plurality of contacts of the electronic device include: contacts for data signals via the I2C communication method, and contacts for clock signals via the I2C communication method arranged on one side of the contacts for data signals; and contacts arranged on the other side of the contacts for data signals as follows: contacts for the second input signal, contacts for an input selection signal via the SPI communication method, contacts for reception via the SPI communication method, contacts for transmission via the SPI communication method, contacts for a clock signal via the SPI communication method, contacts for the first input signal, and contacts for the output signal.

12. The electronic device according to claim 1, wherein The second processing unit determines whether to communicate with the accessory via the second communication method in the case of performing a predetermined operation on the electronic device based on the accessory information.

13. The electronic device according to claim 1, wherein The second processing unit determines whether to communicate with the accessory via the second communication method after performing the predetermined operation based on the accessory information obtained before performing the predetermined operation on the electronic device.

14. The electronic device according to any one of claims 1 to 13, characterized in that, The electronic device is a camera device, and the accessory is a lighting device or a microphone device.

15. An accessory that can be detachably attached to an accessory socket portion of an electronic device, the accessory including an accessory processing unit that can communicate with the electronic device via a first communication method and a second communication method different from the first communication method, It is characterized in that The accessory processing unit sends accessory information for identifying the accessory to the electronic device via the first communication method, and after the accessory processing unit sends the accessory information, communicates with the electronic device via the second communication method for controlling the accessory. Wherein, when the electronic device is in the first power state and the second power state, the accessory processing unit communicates with the electronic device by the first communication method, wherein the power of the second power state is lower than the power of the first power state, and the first power state and the second power state are each a state capable of communicating with the accessory, and Wherein, the accessory processing unit communicates with the electronic device by the second communication method when the electronic device is in the first power state, and does not send information to or receive information from the electronic device by the second communication method when the electronic device is in the second power state, and Wherein, the contacts for sending the accessory information by the first communication method are different from the contacts for controlling the communication of the accessory by the second communication method.

16. The fitting according to claim 15, characterized in that, The communication speed of the first communication method is lower than the communication speed of the second communication method.

17. The fitting according to claim 15, characterized in that, The accessory information includes information related to the type of the accessory and information related to the specifications of the communication and operation of the accessory.

18. The fitting according to claim 15, characterized in that, The accessory processing unit sends the accessory information to the electronic device by the first communication method before the communication by the second communication method is ready.

19. The fitting according to claim 15, characterized in that, The accessory processing unit activates a first input signal input to the electronic device in response to the accessory being attached to the electronic device, activates a second input signal input to the electronic device in response to receiving an output signal output from the electronic device that has detected the first input signal, and communicates with the electronic device that has detected the second input signal by the first communication method.

20. The fitting according to claim 15, characterized in that, The first communication method is an I2C communication method, and the second communication method is an SPI communication method.

21. The fitting according to claim 20, characterized in that, The accessory processing unit activates a first input signal input to the electronic device in response to the accessory being attached to the electronic device, activates a second input signal input to the electronic device in response to receiving an output signal output from the electronic device that has detected the first input signal, and communicates with the electronic device that has detected the second input signal by the first communication method, Wherein, the accessory includes a plurality of contacts arranged in a row, and the plurality of contacts can be electrically connected to a plurality of contacts arranged in a row in the electronic device, and Wherein, the plurality of contacts of the accessory include: Contacts for data signals by the I2C communication method and contacts for clock signals by the I2C communication method arranged on one side of the contacts for data signals; and The following contacts arranged on the other side of the contacts for the data signal: the contacts for the second input signal, the contacts for the input selection signal by the SPI communication method, the contacts for transmission by the SPI communication method, the contacts for reception by the SPI communication method, the contacts for the clock signal by the SPI communication method, the contacts for the first input signal, and the contacts for the output signal.

22. The fitting according to any one of claims 15 to 21, characterized in that, The accessory is a lighting device or a microphone device, and the electronic device is a camera device.

23. A control method for an electronic device, the electronic device being detachably attachable with an accessory, the electronic device including an accessory socket portion to which the accessory can be attached, a first processing unit, and a second processing unit, the control method including the following steps: Causing the first processing unit to receive accessory information for identifying the accessory from the accessory by a first communication method; Causing the second processing unit to communicate with the accessory for controlling the accessory by a second communication method based on the accessory information, wherein the electronic device has a first power state and a second power state, the power of the second power state being lower than the power of the first power state, and each of the first power state and the second power state being a state capable of communicating with the accessory; Causing the first processing unit to communicate with the accessory by the first communication method in the first power state and the second power state; and Causing the second processing unit to communicate with the accessory by the second communication method in the first power state, and prohibiting the second processing unit from sending information to or receiving information from the accessory by the second communication method in the second power state, wherein the contacts for receiving the accessory information by the first communication method are different from the contacts for the communication for controlling the accessory by the second communication method.

24. A control method for an accessory, the accessory being detachably attachable to an accessory socket portion of an electronic device, the control method including the following steps: Causing the accessory to send accessory information for identifying the accessory to the electronic device by a first communication method; After the accessory sends the accessory information, causing the accessory to communicate with the electronic device for controlling the accessory by a second communication method; Causing the accessory to communicate with the electronic device by the first communication method when the electronic device is in a first power state and a second power state, wherein the power of the second power state is lower than the power of the first power state, and each of the first power state and the second power state is a state capable of communicating with the accessory; And When the electronic device is in the first power state, enable the accessory to communicate with the electronic device through the second communication method, and when the electronic device is in the second power state, prohibit the accessory from sending information to or receiving information from the electronic device through the second communication method. Among them, the contacts for sending the accessory information through the first communication method are different from the contacts used for controlling the communication of the accessory through the second communication method.

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