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

Abstract

The present invention provides an electronic device, a control method thereof, an accessory, and a control method thereof. An electronic device that can detachably attach an accessory, the electronic device including a receiving unit and a processing unit. In a case where a first accessory is attached to the electronic device via a second accessory, the receiving unit receives first information from the first accessory indicating whether to permit an operation of the first accessory attached to the electronic device via the second accessory, and the processing unit controls the operation of the first accessory differently according to the first information.

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 main accessory is attached to a camera device, the scalability of the camera system can be improved by attaching an intermediate accessory such as an adapter or an off-camera shoe cord (hereinafter referred to as an off shoe cord) between the camera device and the main accessory. Japanese Patent Application Laid-Open ("JP") 2018-205733 discloses a camera system in which an intermediate accessory is attached between a camera device and a main accessory.

[0003] However, in the camera system disclosed in JP 2018-205733, when only the intermediate accessory is attached to the camera device, the camera device does not detect the attachment of the intermediate accessory, and when the main accessory is attached to the intermediate accessory, the camera device detects the attachment of the main accessory. In this case, the functions of the main accessory that become unavailable due to the attachment of the intermediate accessory cannot be detected and appropriately processed. 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 appropriately handle a main accessory when an intermediate (connecting) accessory is attached between the electronic device and the main accessory.

[0005] An electronic device according to an aspect of the present invention is capable of detachably attaching an accessory, and the electronic device includes a receiving unit and a processing unit. In a case where a first accessory is attached to the electronic device via a second accessory, the receiving unit receives first information indicating whether to permit an operation of the first accessory attached to the electronic device via the second accessory from the first accessory, and the processing unit controls the operation of the first accessory differently according to the first information. 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 is capable of detachably attaching to an electronic device, and the accessory includes an accessory processing unit configured to communicate with the electronic device. In a case where the accessory is attached to the electronic device via an intermediate accessory, the accessory processing unit transmits first information indicating whether to permit an operation of the accessory attached to the electronic device via the intermediate accessory to the electronic device. The control method of the above accessory also constitutes another aspect of the present invention.

[0007] A control method for an electronic device, the electronic device being detachably attachable with an accessory, the control method including the following steps: in a case where a first accessory is attached to the electronic device via a second accessory: receiving first information from the first accessory indicating whether to permit an operation of the first accessory attached to the electronic device via the second accessory, and performing different controls on the operation of the first accessory according to the first information.

[0008] A control method for an accessory, the accessory being detachably attachable to an electronic device, the control method including the following step: sending first information indicating whether to permit an operation of the accessory attached to the electronic device via an intermediate accessory to the electronic device.

[0009] More features of the present invention will become apparent from the following description of exemplary embodiments with reference to the accompanying drawings. 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 showing 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 10 Illustrate a flowchart showing the startup process to be performed by the camera (camera control circuit A) in the first embodiment.

[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 structure of the imaging system (camera, lens unit, intermediate accessory, and main accessory) according to the second embodiment is illustrated.

[0023] Figure 14A The flowchart of the process to be performed by the camera in the second embodiment is illustrated.

[0024] Figure 14B The flowchart of the process to be performed by the camera in the second embodiment is illustrated.

[0025] Figure 15A and Figure 15B The flowchart of the process to be performed by the main accessory in the second embodiment is illustrated.

[0026] Figure 16A and Figure 16B An example of the I2C communication waveform is illustrated.

[0027] Figure 17 The process to be performed by the camera when sending N-byte data from the camera to the accessory in the first embodiment is illustrated.

[0028] Figure 18 The process to be performed by the camera when receiving N-byte data from the accessory by the camera in the first embodiment is illustrated.

[0029] Figure 19A and Figure 19B The process to be performed by the accessory when communicating N-byte data between the camera and the accessory in the first embodiment is illustrated. Detailed Description of the Invention

[0030] Embodiments of the present invention will now be described with reference to the accompanying drawings.

[0031] First Embodiment

[0032] Figure 1Illustrate the electrical structure of a camera system, which includes a camera device (hereinafter referred to as a camera) 100 as an electronic device according to the first embodiment of the present invention and an accessory 200 detachably attached to the camera 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 via 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.

[0033] 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 serving as a first processing unit, a control unit, and a receiving unit, and a camera control circuit B 102 serving as 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 perform various controls and processes according to a computer program.

[0034] The camera control circuit A 101 monitors the operation of a switch or the like used for camera operation (not shown) and controls the system power according to the user's operation. The camera control circuit A 101 includes a low-power type processor that can operate even when the camera 100 is in a power-saving state, which is a low power consumption state. On the other hand, the camera control circuit B 102 is responsible for controlling the image sensor 122, the display circuit 127, and the like. The camera control circuit B 102 includes a processor that stops operating in the low power consumption mode but operates in the normal operation state.

[0035] Although the camera control circuit A 101 and the camera control circuit B 102 include separate processors in this embodiment, the two circuits may be provided in a single processor.

[0036] 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, and the like. The 1.8V voltage generated by the system power supply circuit 112 that receives power from the battery 111 is constantly supplied as the camera microcomputer power supply VMCU_C to the camera control circuit A 101. Several types of voltages generated by the system power supply circuit 112 are supplied as the camera microcomputer power supply VMCU2_C to the camera control circuit B 102 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.

[0037] 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, or the like. 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 or the like 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.

[0038] The memory control circuit 124 controls the transmission and reception of the image data and other data generated by the image processing circuit 123 and the like. The volatile memory 125 is a memory such as DDR3 SDRAM that can perform high-speed reading and writing, and is used as a working 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, and the like. The backlight circuit 128 adjusts the brightness of the display circuit 127 by changing the amount of light of the backlight of the display circuit 127.

[0039] In this embodiment, the accessory power supply circuit A (hereinafter referred to as the accessory power supply circuit A; the first power supply unit) 131 and the accessory power supply circuit B (hereinafter referred to as the accessory power supply circuit B; the second power supply unit) 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.

[0040] 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 (or supply power higher 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.

[0041] 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, etc. 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 can be different from 1 A.

[0042] 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.

[0043] 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.

[0044] 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.

[0045] TC04, which serves as the first ground contact, is connected to GND and used as the reference potential contact for both the camera 100 and the accessory 200. TC04 is arranged outside of TC05 described below along the contact arrangement direction.

[0046] The accessory power supply VACC generated by the accessory power circuits A 131 and B 132 is connected to TC05, which serves as the power contact, via the protection circuit 133.

[0047] The accessory attachment detection signal / ACC_DET is connected to TC06, which serves as the 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, etc.). 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 (GND potential), which is the activation potential, it is detected that the accessory 200 is attached.

[0048] 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.

[0049] In response to detecting the attachment of the accessory 200, the camera control circuit 101 supplies power to the accessory 200 via TC05, which serves as the power contact.

[0050] SCLK connected to TC07, which serves as the communication contact, MOSI connected to TC08, MISO connected to TC09, and Chip Select (CS) connected to TC10 are signals used for communication via the Serial Peripheral Interface (SPI) communication method, which is the second communication method. In the second communication method, the camera control circuit B102 becomes the communication master. SCLK is the clock signal, MOSI is the transmission signal, MISO is the reception signal, and CS is the communication selection signal used as a signal for selecting the 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.

[0051] 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 the SCLK, and is referred to as the SPI protocol A in the following description. Figure 2A Illustrates an overview of the communication waveform of the SPI protocol A. In this figure, CS is active low.

[0052] The camera control circuit B 102 changes CS to a low level (active) at timing A1 and requests SPI communication from the accessory control circuit 201.

[0053] At timing A2, which is a predetermined time T_CS after timing A1, the camera control circuit B 102 starts outputting the SCLK and MOSI. When the accessory control circuit 201 detects the trailing edge of the SCLK, the accessory control circuit 201 starts outputting the MISO.

[0054] The camera control circuit B 102 stops outputting the SCLK at timing A3 when it has completed outputting 1 byte of the SCLK.

[0055] The camera control circuit B 102 stops outputting the SCLK at timing A3 and continues for a predetermined time T_INTERVAL. After T_INTERVAL has elapsed, at timing A4, it restarts outputting the SCLK and performs the next 1-byte communication.

[0056] Figure 3A The flowchart in illustrates the processing to be performed by the camera control circuit B 102 in the SPI protocol A. S represents a step.

[0057] 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, 3 is stored in the case of 3-byte communication.

[0058] In S102, the camera control circuit B 102 changes CS to a low level and requests SPI communication.

[0059] 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 a low level. After the predetermined time T_CS has elapsed, the process proceeds to S104.

[0060] In S104, the camera control circuit B 102 controls the SCLK output, MOSI data output, and MISO data input, and performs 1-byte data communication.

[0061] In S105, the camera control circuit B 102 confirms whether the internal variable N representing the number of communication bytes is 0. When the internal variable N is 0, the process proceeds to S106, and when the internal variable N is not 0, the process proceeds to S107.

[0062] In S107, 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.

[0063] In S108, the camera control circuit B 102 performs a waiting process until a predetermined time T_INTERVAL has elapsed after the 1-byte data communication in S104 is completed. Then, after the predetermined time T_INTERVAL has elapsed, the process returns to the process of S104, and the same process is executed again.

[0064] In S106, the camera control circuit B 102 changes CS to a high level and ends a series of SPI communications.

[0065] Figure 3B The flowchart in [ ] illustrates the processing to be performed by the accessory control circuit 201 in the SPI protocol A.

[0066] In S201, the accessory control circuit 201 confirms whether CS has changed to a low level. When CS has changed to a low level, the process proceeds to S202, and when CS has not changed to a low level, the process returns to S211.

[0067] 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.

[0068] In S203, the accessory control circuit 201 confirms whether CS has changed to a high level. When CS has changed to a high level, it is determined that the SPI communication is completed, and when CS has not changed to a high level, the process returns to S202 to perform the next 1-byte communication.

[0069] 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.

[0070] The camera control circuit B 102 changes CS to 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 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.

[0071] On the other hand, when the accessory control circuit 201 detects the trailing edge of CS at timing B2, the accessory control circuit 201 performs control to change MISO to high level when SPI communication is available, and performs control to change MISO to low level when the communication is unavailable.

[0072] When the camera control circuit B 102 confirms that MISO is at high level at timing B3, the camera control circuit B102 starts outputting SCLK and MOSI. The accessory control circuit 201 starts outputting MISO when it detects the trailing edge of SCLK.

[0073] The camera control circuit B 102 stops outputting SCLK when 1 - byte SCLK output is completed at timing B4.

[0074] After 1 - byte communication, as shown in timings B5 and B6, the accessory control circuit 201 performs control to change MISO to high level when SPI communication is available, and performs control to change MISO to low level when SPI communication is unavailable.

[0075] 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.

[0076] Figure 3C The flowchart in shows the processing to be performed by the camera control circuit B 102 in the SPI protocol B.

[0077] 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.

[0078] In S112, the camera control circuit B 102 changes CS to low level and requests SPI communication.

[0079] In S113, 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 yet at a high level, the process returns to S113.

[0080] In S114, the camera control circuit B 102 controls the SCLK output, MOSI data output, and MISO data input to perform 1-byte data communication.

[0081] In S115, the camera control circuit B 102 confirms whether all data communication has been completed (whether the internal variable N representing the number of communication bytes is 0). When the internal variable N is 0, the process proceeds to S116, and when the internal variable N is not 0, the process proceeds to S117.

[0082] 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.

[0083] In S118, the camera control circuit B 102 confirms whether MISO changes to a high level. When MISO is at a high level, the process proceeds to S114, and when MISO is not at a high level, the process returns to S118.

[0084] In S116, the camera control circuit B 102 changes CS to a high level and ends a series of SPI communications.

[0085] Figure 3D The flowchart in

[0086] In S211, the accessory control circuit 201 confirms whether CS changes to a low level. When CS changes to a low level, the process proceeds to S212, and when CS does not change to a low level, the process returns to S211.

[0087] In S212, the accessory control circuit 201 confirms whether SPI communication is available. When SPI communication is available, the process proceeds to S213, and when SPI communication is not available, the process proceeds to S214.

[0088] In S213, the accessory control circuit 201 performs control to change MISO to a high level, and the process proceeds to S215.

[0089] In S214, the accessory control circuit 201 performs control to change MISO to a low level, and the process returns to S212.

[0090] In S215, the accessory control circuit 201 controls MOSI data input and MISO data output in response to the input of the SCLK signal, and performs 1-byte data communication.

[0091] 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.

[0092] 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.

[0093] The camera control circuit B 102 sends the information CMD indicating 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 indicating 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.

[0094] 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.

[0095] 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.

[0096] 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.

[0097] 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.

[0098] The camera control circuit B 102 transmits 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.

[0099] CheckSum_C = EXOR(AND(SUM(CMD, MOSI_DATA1, …, MOSI_DATA[N-3]), 0xFF), 0xFF)

[0100] The accessory control circuit 201 transmits 0x00 as MISO data.

[0101] Next, the camera control circuit B 102 transmits 0x00 as MOSI data to the accessory control circuit 201 in the Nth byte communication.

[0102] The accessory control circuit 201 transmits the checksum data CheckSum_A as 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.

[0103] CheckSum_A = EXOR(AND(SUM(0xA5, CMD, MIS0_DATA1, …, MOSI_DATA[N-4]), 0xFF), 0xFF)

[0104] 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, the value is calculated by the following expression.

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

[0106] Figure 1TC11, shown as a signal contact (communication request contact), is connected to a 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 a communication request from the accessory 200 by detecting a change (trailing edge) of the communication request signal / WAKE.

[0107] SDA connected to TC12 as a communication contact and 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 a communication master 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.

[0108] 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.

[0109] Figure 16A and Figure 16B An example of an I2C communication waveform is illustrated. Figure 16A An example of a waveform is illustrated in the case where the camera transmits N-byte data (DATA[1] to DATA[N]) to the accessory, and Figure 16B An example of a waveform is illustrated in the case where the camera receives N-byte data (DATA[1] to DATA[N]) from the accessory. In Figure 16A and Figure 16B , the upper waveform illustrates SCL, and the lower waveform illustrates SDA.

[0110] 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 as to whether it is the camera control circuit A 101 or the accessory control circuit 201. The communication data includes data in units of 1 byte 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.

[0111] Since the details of the communication content will be described below with reference to Figures 17 to 19A and Figure 19B the outline will be described with reference to Figure 16A and Figure 16B

[0112] In Figure 16A 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 transmitted. In the third-byte communication to the (N + 2)-byte communication, the camera control circuit A101 transmits N bytes of data (DATA [address] to DATA[address + N]) to the accessory control circuit 201.

[0113] In Figure 16B 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 A101 receives N bytes of data (DATA[address] to DATA[address + N]) from the accessory control circuit 201.

[0114] Figure 17 The flowchart in

[0115] illustrates the processing to be performed by the camera control circuit A101 when the camera control circuit A101 transmits N bytes of data to the accessory control circuit 201.

[0116] In S3001, the camera control circuit A101 stores the value indicating the number of bytes to be transmitted in the internal variable N. For example, in the case of transmitting 3 bytes, 3 is stored. In this embodiment, 3 is stored.

[0117] In S3002, the camera control circuit A101 changes the SDA to low level during the period when the SCL is at high level (start (START) condition). Thereby, it notifies the accessory control circuit 201 of the start of communication. ​

[0118] In S3004, the camera control circuit A101 sets the lowermost bit of the transmission data to information indicating write communication. Setting this bit to 0 means write communication.

[0119] In S3005, the camera control circuit A101 transmits the data set as the transmission data in S3003 and S3004 (10100000 in binary and 0xA0 in hexadecimal) to the accessory control circuit 201.

[0120] In S3006, after transmitting 1-byte data, the camera control circuit A101 outputs SCL and holds 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 normally received the data, and the process proceeds to S3014.

[0121] In S3007, the camera control circuit A101 sets the storage address information (start address information) of the data to be transmitted to 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.

[0122] In S3008, the camera control circuit A101 transmits the set 1-byte start address information (value 0x00) to the accessory control circuit 201.

[0123] In S3009, after transmitting 1-byte start address information data, the camera control circuit A101 outputs SCL and holds 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 normally received the data, and the process proceeds to S3014.

[0124] In S3010, the camera control circuit A101 stores 1 in the internal variable M. The internal variable M is a variable for counting the number of transmission data.

[0125] In S3011, the camera control circuit A 101 outputs 1 byte of SCL and changes SDA to the desired signal level while SCL is at a low level to output 1 byte of data to the accessory control circuit 201. Here, the start address information is 0x00 and the internal variable M is 1, so 1 byte of data corresponding to the address 0x00 is sent.

[0126] In S3012, after the camera control circuit A 101 sends 1 byte of data, it outputs SCL for one clock and confirms the signal level of SDA. When the signal level of SDA is low, it is judged 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 judged that the accessory control circuit 201 has not received the data normally, and the process proceeds to S3014.

[0127] In S3013, the camera control circuit A 101 confirms whether the internal variable M has the same value as the internal variable N. When the internal variable M has the same value as the internal variable N, it is judged that the transmission of all data is completed, and the process proceeds to S3014. When the internal variable M does not have the same value as the value of the internal variable N, it is judged that there is still data to be sent, and the process proceeds to S3015.

[0128] In S3015, the camera control circuit A 101 adds 1 to the internal variable M, and the process returns to S3011.

[0129] Therefore, after the process returns to S3011, the camera control circuit A 101 sequentially increments the address of the data to be sent and sends 1 byte of data corresponding to each address. In this way, the camera control circuit A 101 sends N bytes of data to the accessory control circuit 201 by repeating the transmission of 1 byte of 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 bytes of data can be sent.

[0130] In S3014, the camera control circuit A 101 changes SDA to a high level (stop (STOP) condition) while SCL is at a high level. Thereby, the communication end is notified to the accessory control circuit 201.

[0131] Figure 18 The flowchart in shows the processing that the camera control circuit A 101 has to perform when the camera control circuit A 101 receives N bytes of data from the accessory control circuit 201.

[0132] In S3101, the camera control circuit A 101 stores the numerical value indicating the number of bytes to be received in the internal variable N. For example, when receiving 3-byte data, 3 is stored. In this embodiment, 3 is stored.

[0133] 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.

[0134] 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.

[0135] In S3108, the camera control circuit A 101 transmits the set 1-byte start address information (value 0x00) to the accessory control circuit 201.

[0136] In S3109, after transmitting the 1-byte start address information data, the camera control circuit A 101 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.

[0137] In S3110, similar to S3102, the camera control circuit A 101 changes SDA to low level while SCL is at high level, and notifies the accessory control circuit 201 of the start condition.

[0138] In S3111, the camera control circuit A 101 sets the slave device address information indicating the slave device address of the accessory control circuit 201 to the high 7 bits of the transmission data. In this embodiment, it is assumed that the slave device address of the accessory control circuit 201 is 1010000 in binary.

[0139] In S3112, the camera control circuit A 101 sets the information indicating the read communication to the low 1 bit of the transmission data. Setting this bit to 1 means read communication.

[0140] In S3113, the camera control circuit A 101 transmits the data set as the transmission data in S3003 and S3004 to the accessory control circuit 201 (10100001 in binary and 0xA1 in hexadecimal).

[0141] 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 a 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.

[0142] 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.

[0143] In S3116, the camera control circuit A 101 outputs 1-byte SCL and reads the signal level of SDA at the timing when SCL changes from low level to high level. This configuration enables receiving 1-byte data from the accessory control circuit 201. The received 1-byte data can be stored in the volatile memory 125 as the data corresponding to the address 0x00 or used for a predetermined process.

[0144] In S3117, the camera control circuit A 101 determines whether 1-byte data has been received normally. When received normally, the process proceeds to S3118. When not received normally, the process proceeds to S3119.

[0145] 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.

[0146] 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 SCL and by performing control to change SDA to low level.

[0147] In S3121, the camera control circuit A 101 adds 1 to the internal variable M, and the process returns to S3116.

[0148] 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 data corresponding to each address. In this way, the camera control circuit A 101 receives N-byte data from the accessory control circuit 201 by repeatedly receiving 1-byte data until the internal variable M and the internal variable N have the same value in the process of S3118. When the internal variable N is set to 3 as in this embodiment, 3-byte data can be received.

[0149] In S3119, the camera control circuit A 101 outputs 1-byte SCL, and performs control to change SDA to high level to notify the accessory control circuit 201 of the completion of data communication (NACK).

[0150] In S3122, the camera control circuit A 101 changes SDA to high level (stop condition) while SCL is at high level. Thereby, the end of communication is notified to the accessory control circuit 201.

[0151] Figure 19A and Figure 19B The flowchart in 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.

[0152] 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.

[0153] In S3202, the accessory control circuit 201 stores 0 in the internal variable M. The internal variable M is a variable for counting the number of transmitted data and the number of received data.

[0154] In S3203, the accessory control circuit 201 receives 1-byte data sent from the camera control circuit A 101.

[0155] 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). When the address is the same as the slave address of the accessory control circuit 201, the process proceeds to S3205. When the address is not the same as the slave address of the accessory control circuit 201, the process proceeds to S3221.

[0156] In S3205, the accessory control circuit 201 provides a data reception notification (ACK) to the camera control circuit A 101 by controlling the SDA to be changed to a low level for the next SCL clock output after receiving 1-byte data.

[0157] In S3206, the accessory control circuit 201 determines the type of data for the next 1-byte communication based on the lower 1-bit data of the 1-byte data received in S3203. When the lower 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. When the lower 1-bit data is 1, it is determined that the data for the next 1-byte communication is the data to be sent from the accessory control circuit 201 to the camera control circuit A 101, and the process proceeds to S3209.

[0158] 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 sent and received in the subsequent communication. In this embodiment, as referred to in Figure 17 and Figure 18 it is assumed that the start address information is 0x00.

[0159] 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.

[0160] In S3208, when the accessory control circuit 201 determines that 1-byte data can be normally received, the process proceeds to S3210. When it is determined that 1-byte data cannot be normally received, the process proceeds to S3221.

[0161] In S3210, the accessory control circuit 201 provides a data reception notification (ACK) to the camera control circuit A101 by controlling the SDA to be changed to a low level for the next SCL clock output after receiving 1-byte data.

[0162] In S3211, the accessory control circuit 201 confirms whether SDA changes to low level (start condition) during the period when SCL is at high level. When the accessory control circuit 201 detects the start condition, the accessory control circuit 201 determines that the 1-byte data to be communicated next is the 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 1-byte data to be communicated next is the data information received by the accessory control circuit 201 from the camera control circuit A 101. Then, the process proceeds to S3216.

[0163] In S3212, the accessory control circuit 201 receives 1-byte data sent from the camera control circuit A 101.

[0164] 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 this 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.

[0165] In S3214, the accessory control circuit 201 determines the data type for the next 1-byte communication based on the low 1-bit data of the 1-byte data received in S3203. When the low 1-bit data is 0, the process proceeds to S3221. When 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 A101, and the process proceeds to S3215.

[0166] In S3215, 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 1-byte data.

[0167] In S3222, the accessory control circuit 201 sends 1-byte data corresponding to the start address information received from the camera control circuit A 101 in S3207 or the start address information determined in S3209 to the camera control circuit A 101.

[0168] In S3223, the accessory control circuit 201 adds 1 to the internal variable M, and the process proceeds to S3224.

[0169] In S3224, after transmitting 1 byte of data, the accessory control circuit 201 confirms the signal level of SDA. When the signal level of SDA is high, the camera control circuit A 101 determines that this is a notification (NACK) of receiving all data, and the process proceeds to S3225. On the other hand, when the signal level of SDA is low, it is determined that the camera control circuit A 101 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 transmitted and transmits 1 byte of data corresponding to each address. Thus, by repeatedly transmitting 1 byte of data from the camera control circuit A 101 until NACK is notified in the process of S3224, the accessory control circuit 201 transmits N bytes of data to the camera control circuit A 101.

[0170] In S3225, the accessory control circuit 201 waits for a stop condition where SDA changes to high while SCL is at a high level. When the accessory control circuit 201 detects the stop condition, the communication is terminated.

[0171] On the other hand, in S3216, the accessory control circuit 201 receives 1 byte of data and stores the 1 byte of 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 of data for a predetermined process.

[0172] In S3217, the accessory control circuit 201 adds 1 to the internal variable M, and the process proceeds to S3218.

[0173] In S3218, if the accessory control circuit 201 determines that 1 byte of data can be normally received, the process proceeds to S3219. If it is determined that 1 byte of data cannot be normally received, the process proceeds to S3221.

[0174] 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 low for the next SCL clock output after receiving 1 byte of data.

[0175] In S3230, the accessory control circuit 201 confirms whether it has detected a stop condition, under which SDA changes to high level while SCL is at 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 sent from the camera control circuit A 101 to the accessory control circuit 201. Then, the process returns to S3216.

[0176] 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 A 101.

[0177] Therefore, the camera connector 141 includes contacts TC12 for data signals by the I2C communication method, and contacts TC13 for clock signals by 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 by the SPI communication method, contacts TC09 for reception by the SPI communication method, contacts TC08 for transmission by the SPI communication, contacts TC07 for a clock signal by 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).

[0178] 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) of the accessory 200. Figure 5 An example of the accessory information is illustrated. 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.

[0179] Connected to Figure 1The FNC1 signal of TC14 serving as a communication contact, the FNC2 signal connected to TC15, the FNC3 signal connected to TC16, and the FNC4 signal connected to TC17 are functional signal whose functions vary 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.

[0180] Signals with different functions can be communicated via the same contact 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 functional signal contacts. The communication using at least one of the functional signal contacts will also be referred to as functional signal communication. The functional signal communication can be executed at a timing independent of the I2C communication and the SPI communication in parallel with the I2C communication and the SPI communication.

[0181] As used herein, the accessory type means the above-mentioned microphone device, lighting device, 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 a microphone device and a lighting device) are different types of accessories. The functional signal communication is executed based on the information obtained through the I2C communication or the SPI communication. TC18 serving as a second ground contact is also connected to GND, and similar to TC04, is a contact serving as the reference potential of 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 that 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.

[0182] 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.

[0183] 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.

[0184] In the present embodiment, the attachment detection contact TC06 to which the accessory attachment detection signal / ACC_DET is connected is arranged adjacent to the contact (first clock contact) TC07 that transmits the transmission clock signal SCLK (first clock signal). Generally, noise (clock noise) associated with potential fluctuations in the clock signal is transmitted to contacts adjacent to the contact of the clock signal, which may cause malfunctions. In particular, as in the present embodiment, this effect is significant in a configuration having many contacts with a short distance between the contacts. Therefore, by arranging the attachment detection contact TC06 adjacent to the SCLK contact TC07, the influence of the clock noise can be suppressed.

[0185] 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.

[0186] When the SCLK contact TC07 transmits the clock signal, the attachment detection contact TC06 is at the GND potential. Therefore, even if the attachment detection contact TC06 receives clock noise, it is unlikely that the potential of the control circuits of the camera 100 and the accessory 200 will fluctuate, thereby preventing malfunctions. In addition, the clock noise can be suppressed from being transmitted to a position farther than the accessory detection contact TC06. As a result, there is no need to provide a GND terminal, and thus the influence of the clock noise can be suppressed without increasing the number of contacts.

[0187] SCL (second clock signal) as the clock signal is also transmitted to the 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.

[0188] Except for the difference in frequency, the SCL sent by the SCL contact TC13 is the 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 sent by the SCLK contact TC07 is the 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 less likely to generate clock noise. Therefore, arranging the attachment detection contact TC06 next to the SCLK contact TC07 rather than next to the SCL contact TC13 is more effective in preventing failures caused by clock noise.

[0189] The differential signals D1N and D1P can be sent in pairs to the first differential signal contact TC19 and the second differential signal contact TC20 to send a clock signal. In this case, a clock signal (third clock signal) with a frequency higher than that of the SCLK contact TC07 and the SCL contact TC13 can be sent. However, since the differential signals D1N and D1P are paired signals, the clock noise emission is smaller than that of the SCLK contact TC07 and the SCL contact TC13 that send single-ended signals. Therefore, it is more effective to prevent failures caused by clock noise by arranging the attachment detection contact TC06 next to the SCLK contact TC07 rather than next to the first differential signal contact TC19 and the second differential signal contact TC20.

[0190] The contact (first data contact) TC08 arranged on the opposite side of the attachment detection contact TC06 next to the SCLK contact TC07 sends MOSI (first data signal). Since MOSI is a data signal, MOSI seems vulnerable to clock noise. However, MOSI is the data signal of the same SPI communication standard as the clock signal sent by the SCLK contact TC07, so the potential fluctuation timing is synchronized with the clock signal and less likely 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.

[0191] 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.

[0192] 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 microcomputer power supply VMCU_A to the accessory control circuit 201. 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 and off control of the power supply to each circuit in the accessory 200.

[0193] The charging circuit (power receiving unit) 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 to perform the charging operation, the accessory control circuit 201 controls the charging circuit 204 to charge the battery 205. In the present embodiment, the battery 205 is attached to the accessory 200, but the accessory 200 can operate only by supplying power from the camera 100 to the accessory power supply circuit (power receiving unit) 202 without the battery 205 attached. In this case, the charging circuit 204 is unnecessary.

[0194] The differential communication circuit 207 is a circuit for performing 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 performing 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, etc. 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.

[0195] The function 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 function circuit 206 is, for example, a light emitting circuit or a charging circuit, etc. When the accessory 200 is a microphone device, the accessory 200 is a voice codec circuit or a microphone circuit, etc.

[0196] The external connection terminal 209 is a connector terminal for connecting to an external device, and is a USB TYPE-C connector in the present 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.

[0197] The power switch 203 is a switch that can be operated by the user to turn on and off the power supply (i.e., operation) of the accessory 200. 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.

[0198] 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, a touch sensor, etc. When the operation switch 212 is operated, the accessory control circuit 201 detects the operation and executes a predetermined process according to the operation.

[0199] 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.

[0200] 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.

[0201] The differential signal D1N connected to TA02 and the differential signal D1P connected to TA03 are data communication signals that 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.

[0202] TA04, which is the first ground contact, is connected to GND and is used as a reference potential contact for the camera 100 and the accessory 200. TA04 is arranged outside TA05 described below in the arrangement direction of the contacts.

[0203] The accessory power supply circuit 202 and the charging circuit 204 are connected to TA05, which is a power supply contact, and the accessory power supply VACC supplied from the camera 100 is connected to TA05.

[0204] 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 an active potential. Thereby, the camera 100 can detect the attachment of the accessory 200.

[0205] The SCLK connected to TA07 which serves as a communication contact, the MOSI connected to TA08, the MISO connected to TA09, and the CS connected to TA10 are signals for the accessory control circuit 201 to act as a communication slave for SPI communication.

[0206] The communication request signal / WAKE for requesting communication from the accessory control circuit 201 to the camera 100 is connected to TA11 which serves as 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.

[0207] 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.

[0208] Even if there is no request from the camera, the accessory control circuit 201 can notify the existence 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 a high level to a low level. With this configuration, the camera control circuit 101 can omit the operation of periodically checking whether the accessory 200 has a factor that requires communication by polling. When a communication required factor occurs, the accessory 200 can communicate with the camera 100 in real time.

[0209] The SDA connected to TA12 which serves as a communication contact and the SCL connected to TA13 are signals for the accessory control circuit 201 to act as a communication slave for I2C communication.

[0210] Therefore, the accessory connector 211 includes the contact TA12 for data signals by the I2C communication method, and the 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 further includes, on the other side of the contact TA12 for data signals (sequentially starting from the position adjacent to the contact TA12 for data signals on the other side), the contact TA11 for the second input signal, the contact TA10 for the input selection signal by the SPI communication method, the contact TA09 for transmission by the SPI communication method, the contact TA08 for reception by the SPI communication method, the contact TA07 for the clock signal by the SPI communication method, the contact TA06 for the first input signal, and the contact TA06 for the output signal.

[0211] The FNC1 signal connected to TA14 (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 may be signals related to voice data, and when the accessory 200 is a flash device, these signals may be signals for notifying the light emission timing.

[0212] TA18, as the second ground contact, is also connected to GND and, similar to TA04, is the reference potential contact for both 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 data communication in pairs and are connected to the external connection terminal 209.

[0213] 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 the differential signals D2N and D2P. TA21 corresponds to the fourth ground contact.

[0214] The 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 a screw (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.

[0215] Figure 6Illustrate the processing sequence to be performed when the accessory 200 is attached to the camera 100. Now, the processing outlines 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.

[0216] 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 supply circuit A 131. When the power control signal CNT_VACC1 becomes high, the accessory power supply circuit A 131 outputs the accessory power VACC.

[0217] The accessory power supply circuit 202 that receives VACC generates the power VMCU_A for the accessory control circuit 201. Thereby, the accessory control circuit 201 starts up. 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.

[0218] 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 the 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.

[0219] 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.

[0220] Based on the notified accessory information, the camera control circuit B 102 notifies the control command (accessory control communication) to the accessory 200 through SPI communication or performs control corresponding to the function signal (function signal control). That is, the camera control circuit B 102 controls the accessory 200 through SPI communication.

[0221] The accessory control circuit 201 responds to control commands from the camera 100 via SPI communication and operates according to the function signal.

[0222] Now, the Figure 5 accessory information shown 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 accessory type information are illustrated. For example, 0x81 indicates a flash device, 0x82 indicates an interface conversion adapter device, 0x83 indicates a microphone device, and 0x84 indicates a multi - accessory connection adapter device for attaching multiple accessory devices to the camera 100.

[0223] 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.

[0224] Figure 5 The D7 - D0 data at address 0x01 in [] is information indicating the model (type) of the accessory 200 (hereinafter referred to as accessory type information). The type and model of the accessory can be identified by the above - mentioned accessory type information and this information.

[0225] The D7 - D0 data at address 0x02 is information indicating the firmware version of the accessory 200.

[0226] 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 in the power - off state where 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 circuit A 131 requests power supply. When this information is 2, the accessory power circuit B 132 requests power supply.

[0227] 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 accessory power VACC from 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 lasts 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 requested by the accessory power supply circuit A131. When this information is 2, it means that there is a power supply requested by the accessory power supply circuit B 132.

[0228] The D3-D2 data at address 0x03 is specification information indicating whether the accessory 200 has a 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.

[0229] 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.

[0230] 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. In order 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.

[0231] 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.

[0232] The D6 data at address 0x05 is specification information indicating whether the accessory 200 has a firmware update function. When this information is 0, it means that the accessory 200 does not have a firmware update function. When this information is 1, it means that the accessory 200 has a firmware update function.

[0233] The D5-D4 data at address 0x05 is specification information indicating whether the operation of the accessory 200 attached to the intermediate (connecting) 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.

[0234] The D3-D2 data at address 0x05 is specification information indicating whether the accessory 200 needs the camera 100 to confirm the attachment 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.

[0235] 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.

[0236] The D5-D4 data at address 0x06 is specification information indicating a communication request factor acquisition method (the communication method used: hereinafter referred to as the factor acquisition method) for 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 camera 100 of the communication request signal / WAKE. 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 factor acquisition methods.

[0237] 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 this value is 0, it means that the accessory 200 does not have this function. When this value is 1, the accessory 200 has this function.

[0238] The D7 data at address 0x0A is specification information indicating whether accessory 200 requests camera 100 to start when accessory 200 notifies communication request signal / WAKE to camera 100. When this information is 0, it means a start request, and when this information is 1, it means no start request.

[0239] The D6 - D0 data at address 0x0A is information indicating the generation factor of the communication request signal / WAKE that accessory 200 notifies camera 100.

[0240] 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 accessory 200 is a microphone device is illustrated. For example, factor number 0x00 is the number indicating that the menu call switch in operation switch 212 has been operated (pressed). Factor number 0x01 is the number indicating that accessory 200 has completed the output control of the audio signal. Factor number 0x02 is the number indicating that accessory 200 has completed the mute (unmute) process of the audio signal. As described above, in this embodiment, 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 accessory 200 to camera 100 as accessory information.

[0241] In Figure 5 the D1 data at address 0x0C is specification information indicating the SPI communication protocol supported by accessory 200. When this information is 0, it means accessory 200 supports SPI protocol A, and when this information is 1, it means accessory 200 supports SPI protocol B.

[0242] The D0 data at address 0x0C is specification information indicating the CS control logic of the SPI communication supported by 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.

[0243] The D7 - D0 data at address 0x0D is specification information indicating the time required as the communication byte interval when accessory 200 communicates according to SPI protocol A and the D7 data at address 0x05 is 0, or when accessory 200 is not in the firmware update mode.

[0244] The D7 - D0 data at address 0x0E is specification information indicating the time required as the communication byte interval when accessory 200 communicates according to SPI protocol A and the D7 data at address 0x05 is 1, or when accessory 200 is in the firmware update mode.

[0245] Figure 9A and Figure 9B Illustrate the communication byte interval time (communication 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.

[0246] In Figure 5 the data at address 0x0F is the checksum value data representing the sum of the values at addresses 0x00 to 0x0E.

[0247] 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 function of the accessory 200 is enabled.

[0248] In S401, the camera control circuit A 101 monitors the signal level of the accessory attachment detection signal / ACC_DET and determines (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 determines that the accessory 200 is not attached, and the process returns to S401. Therefore, the camera control circuit A101 determines again whether the accessory 200 is attached. If the signal level is low, the camera control circuit A 101 determines that the accessory 200 is attached, and the process proceeds to S402.

[0249] 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 VACC.

[0250] 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, and if the signal level is high, the camera control circuit A101 determines that an overcurrent is flowing, and the process proceeds to S405 for error handling.

[0251] In S404, the camera control circuit A 101 monitors the signal level of the communication request signal / WAKE, which is a notification signal from the accessory 200, and determines whether the initialization of the accessory 200 is completed. If the signal level of the communication request signal / WAKE is low (active), the camera control circuit A 101 determines that the initialization is completed, and the process proceeds to S406. If the signal level is high, the camera control circuit A 101 determines that the initialization has not been completed, and the process returns to S404, so that the camera control circuit A 101 determines again whether the initialization is completed.

[0252] In S406, the camera control circuit A 101 performs I2C communication with the accessory 200 as the initial communication and reads 15 bytes of accessory information. Then, the process proceeds to S407.

[0253] 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. When the camera control circuit A 101 determines that the attached accessory 200 is a compatible accessory, the process proceeds to S408, and when the camera control circuit A 101 determines that the attached accessory 200 is not a compatible accessory, the process proceeds to S409 for error handling.

[0254] 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 circuit B 132. Then, the process proceeds to S410. When the power control signal CNT_VACC2 is at a high level, the accessory power 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 circuit B 132 is supplied to the accessory power VACC.

[0255] 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.

[0256] Figure 11 The flowchart in shows the enabling process to be executed by the camera control circuit B 102 until the accessory 200 is attached to the camera 100 and the functions of the accessory 200 are enabled.

[0257] 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.

[0258] 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.

[0259] 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.

[0260] 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.

[0261] 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.

[0262] 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 the function signals. If the event requires control using the function signals, the process proceeds to S508; otherwise, the process proceeds to S509.

[0263] 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 of an instruction to turn on the microphone operation, communication of an instruction to turn off the microphone operation, communication of an instruction to switch the sound collection directivity of the microphone, and communication of an instruction to switch the equalizer function of the microphone, etc. 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, etc. 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.

[0264] In S508, the camera control circuit B 102 controls the accessory 200 using function signals. 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. Thereby, 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. Thereby, 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.

[0265] 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, etc. 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, etc. 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.

[0266] Through the above-mentioned startup 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.

[0267] Figure 12The flowchart in illustrates the processing to be performed by the accessory control circuit 201 from when the accessory 200 is attached to the camera 100 until various functional operations of the accessory 200 are enabled.

[0268] 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.

[0269] 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.

[0270] When the initial settings in S602 are completed, in S603, the accessory control circuit 201 performs control to change the communication request signal / WAKE to a low level. Thereby, the camera 100 is notified that the initial settings are completed.

[0271] In S604, the accessory control circuit 201 responds to the I2C communication from the camera 100 and sends 15-byte accessory information to the camera 100 as the initial communication. The accessory information includes Figure 5 the various information shown.

[0272] 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.

[0273] 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.

[0274] 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.

[0275] 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.

[0276] 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.

[0277] 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 the communication request signal / WAKE. If the event requires notification to the camera 100 via the communication request signal / WAKE, the process proceeds to S614; otherwise, the process proceeds to S615.

[0278] 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 start the microphone operation from the camera 100, communication for an instruction to stop 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 the 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.

[0279] 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 the communication request factor (number) 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.

[0280] 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.

[0281] In S614, the accessory control circuit 201 stores the communication request factor number for 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.

[0282] 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, control for detecting the operation of the operation switch 212, and the like. 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.

[0283] 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.

[0284] Second Embodiment

[0285] Figure 13Illustrate the electrical structure of the imaging system according to the second embodiment of the present invention. In this imaging system, between the camera 100 and the accessory (the first accessory: hereinafter referred to as the main accessory) 200 of the first embodiment, an off-shoe cable 300 as an intermediate accessory (the second accessory) is attached. The off-shoe cable 300 is usually referred to as an off-camera shoe cable and includes off-shoe cable connectors 311 and 341 that can be connected to the camera 100 and the main accessory 200, and a cable (wire harness) portion that bundles a plurality of signal lines connecting these connectors. The camera 100 and the main accessory 200 are the same as the camera 100 and the main accessory 200 of the first embodiment. Instead of the off-shoe cable 300, another intermediate accessory can be used.

[0286] When a plurality of contacts TC01 to TC21 of the camera connector 141 provided in the camera 100 are connected one-to-one with a plurality of contacts TA01 to TA21 of the off-shoe cable connector 311 provided in the off-shoe cable 300, the camera 100 and the off-shoe cable 300 are electrically connected. When a plurality of contacts TC01 to TC21 of the off-shoe cable connector 341 provided in the off-shoe cable 300 are connected one-to-one with a plurality of contacts TA01 to TA21 of the accessory connector 211 provided in the accessory 200, the off-shoe cable 300 and the main accessory 200 are electrically connected.

[0287] In the case where only the off-shoe cable 300 is connected to the camera 100, TA06 in the off-shoe cable connector 311 is connected to TC06 to which the accessory attachment detection signal / ACC_DET in the camera connector 141 is connected. However, since the signal level of the accessory attachment detection signal / ACC_DET does not change, the camera control circuit A 101 cannot detect (judge) whether the off-shoe cable 300 is attached. When the main accessory 200 is connected to the off-shoe cable 300, the signal level of the accessory attachment detection signal / ACC_DET becomes low, and the camera control circuit A 101 detects the attachment of the main accessory 200.

[0288] The off-shoe cable power supply circuit 301 is a circuit that generates power to be supplied to the off-shoe cable non-volatile memory 302 and includes an LDO or the like. When the accessory power supply VACC is supplied from the camera 100, power can be supplied from the off-shoe cable power supply circuit 301 to the off-shoe cable non-volatile memory 302.

[0289] Similar to Figure 5 the 15-byte accessory information stored in the main accessory 200 shown, the off-shoe cable non-volatile memory 302 stores various information.

[0290] The off-shoe connecting cable connector 311 is a connector 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. The off-shoe connecting cable connector 341 is a connector electrically connected 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.

[0291] TA05 and TC05 are connected as a power path, and when power VACC for the accessory is supplied from the camera 100, power can be generated by the off-shoe connecting cable power circuit 301. The contacts TA06 to TA17 in the off-shoe connecting cable connector 311 are connected to the contacts TC06 to TC17 in the off-shoe connecting cable connector 341.

[0292] In Figure 13 the contacts TA01 to TA03 and TA19 to TA21 in the off-shoe connecting cable connector 311 are not connected to the contacts TC01 to TC03 and TC19 to TC21 in the off-shoe connecting cable connector 341, but can be connected. At least a part of the contacts TA01 to TA03 and TA19 to TA21 in the off-shoe connecting cable connector 311 and at least a part of the contacts TC01 to TC03 and TC19 to TC21 in the off-shoe connecting cable connector 341 can be omitted. Since the diameter of the connecting portion of the off-shoe connecting cable 300 increases as the number of signal lines connecting the respective connectors increases, the increase in the size of the off-shoe connecting cable 300 can be suppressed by eliminating signal lines that are not common to various devices assumed as the main accessory.

[0293] The contacts TA12 and TA13 in the off-shoe connecting cable connector 311 are connected to the contacts TC12 and TC13 in the off-shoe connecting cable connector 341, and are further connected to the off-shoe connecting cable non-volatile memory 302 as communication lines for I2C communication from the camera 100.

[0294] Figure 14A The flowchart of

[0295] In S801, the camera control circuit A 101 monitors the signal level of the accessory attachment detection signal / ACC_DET and determines (detects) whether the main accessory 200 is attached. If the signal level of / ACC_DET is high (H), the camera control circuit A 101 determines that the accessory 200 is not attached, and the process returns to S801 so that the camera control circuit A 101 determines again whether the accessory 200 is attached. If the signal level is low (L), it is determined that the main accessory 200 is attached, and the process proceeds to S802.

[0296] In S802, the camera control circuit A 101 performs control to change the power control signal CNT_VACC1 to a high level (H) to turn on the output of the accessory power supply circuit A131. Then, the process proceeds to S803. When the power control signal CNT_VACC1 is at a high level, the accessory power supply circuit A 131 outputs the accessory power VACC.

[0297] In S803, 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 (L), the camera control circuit A 101 determines that an overcurrent is not flowing and the process proceeds to S804, and if the signal level is high, the camera control circuit A101 determines that an overcurrent is flowing and the process proceeds to S805 to perform error processing.

[0298] In S804, the camera control circuit A 101 monitors the signal level of the communication request signal / WAKE, which is a notification signal from the main accessory 200, and determines whether the initialization of the main accessory 200 is completed. If the signal level of / WAKE is low (active; L), the camera control circuit A 101 determines that the initialization is completed, and the process proceeds to S806. If the signal level is high, the camera control circuit A 101 determines that the initialization has not been completed, and the process returns to S804 to determine the completion of the initialization again.

[0299] In S806, the camera control circuit A 101 performs I2C communication with the main accessory 200 as initial communication and reads 15 bytes of accessory information. Then, the process proceeds to S807.

[0300] In S807, the camera control circuit A 101 performs a detachable cable connection determination process based on the accessory information read in S806. The detachable cable connection determination process will be described below.

[0301] Next, in S808, the camera control circuit A 101 determines whether the determination result in the off-shoe connection determination process performed in S807 is "operation not permitted when the off-shoe connection is attached", and if the determination result is "operation not permitted when the off-shoe connection is attached", the process proceeds to S809; otherwise, the process proceeds to S810.

[0302] In S809, the camera control circuit A 101 disconnects the accessory power supply VACC for error handling so that the main accessory 200 cannot operate. That is, the camera control circuit A 101 (and the camera control circuit B 102) restricts the operation of the main accessory 200. The camera control circuit A 101 notifies the user through the display circuit 127 that the use of the main accessory 200 is restricted. At this time, a message such as "no available accessory" can be displayed on the display circuit 127.

[0303] The restriction on the operation of the main accessory 200 when the main accessory 200 is inoperable can be a restriction other than disconnecting the accessory power supply VACC as described above. For example, the user can permit the operation of the main accessory 200 through the menu screen (setting unit) of the camera 100, and control the operation of the main accessory 200 under the condition that the user sets the operation permission. Another restriction can be to disable the operations associated with the camera 100 in the operation of the main accessory 200 and enable another operation not associated with the camera 100.

[0304] In S810, the camera control circuit A 101 performs control to change the power control signal CNT_VACC2 to a high level (H) to turn on the output of the accessory power supply circuit B 132. Then, the process proceeds to S811. When the power control signal CNT_VACC2 is at a high level, the accessory power supply circuit B 132 outputs the accessory power supply VACC. In this embodiment, when both the power control signals CNT_VACC1 and CNT_VACC2 become high, the output from the accessory power supply circuit B 132 is supplied to the accessory power supply VACC.

[0305] In S811, the camera control circuit A 101 notifies the camera control circuit B 102 of the accessory information read in S806.

[0306] Next, in S812, the camera control circuit A 101 determines whether the determination result in the off-shoe connection determination process performed in S807 is "operation permitted when the off-shoe connection is attached" or "normal operation". If the determination result is "operation permitted when the off-shoe connection is attached", the process proceeds to S813, and if the determination result is "normal operation", S813 is skipped to complete the startup process of the camera 100.

[0307] In S813, the camera control circuit A 101 permits a change in control in a state where the off-shoe cable 300 is attached.

[0308] That is, the camera 100 provides different controls between a case where the main accessory 200 operates in a state where the off-shoe cable 300 is attached and a case where the main accessory 200 operates in a state where the off-shoe cable 300 is not attached. For example, this change is used in a case where the main accessory 200 is a camera unit, an image obtained by imaging through the camera unit is acquired by the camera unit 100, and an image obtained by imaging through the camera 100 is synthesized with the image obtained by imaging through the camera unit.

[0309] Since the optical axis offset amount between the camera unit and the camera 100 can be obtained in advance in a state where the off-shoe cable 300 is not attached, the image synthesis process is performed based on the preliminarily obtained optical axis offset amount. On the other hand, in a state where the off-shoe cable 300 is attached, the optical axis offset amount between the camera unit and the camera 100 cannot be obtained in advance. Therefore, the display circuit 127 displays the fact that the optical axis offset amount is unknown and a screen that enables the user to input the optical axis offset amount. In addition, in a case where the main accessory 200 is used to obtain an evaluation value of a subject of the camera 100 and a change in the distance between the camera 100 and the main camera 200 affects the evaluation value, S812 and S813 can be executed. Then, the startup process of the camera 100 is completed.

[0310] Figure 14B The flowchart example shows the off-shoe cable determination process to be performed by the camera control circuit A 101 in S807.

[0311] In S901, the camera control circuit A 101 confirms whether it is necessary to confirm the attachment of the off-shoe cable 300 based on the startup intermediate accessory confirmation information (second information) which is the D3 - D2 data at address 0x05 in the accessory information read in S806. As described above, the startup intermediate accessory confirmation information is information indicating whether the main accessory 200 requires the camera 100 to confirm the attachment of the intermediate accessory when the camera 100 starts up. If it is necessary to confirm the attachment of the off-shoe cable 300, the process proceeds to S902, and if it is not necessary to confirm the attachment of the off-shoe cable 300, the process proceeds to S907.

[0312] In S902, the camera control circuit A 101 reads out the accessory information stored in the off-shoe connection non-volatile memory 302 in the off-shoe connection 300 through I2C communication. At this time, the camera control circuit A 101 reads out the accessory information stored in the off-shoe connection non-volatile memory 302 via the same serial communication line (contacts TA12, TA13, TC12, and TC13) as the serial communication line used to read the accessory information stored in the main accessory 200. In this embodiment, the I2C slave device address (memory address) is different between the case of reading the accessory information stored in the off-shoe connection non-volatile memory 302 and the case of reading the accessory information stored in the main accessory 200, and thus it is possible to identify the source of the read accessory information. The camera control circuit A 101 can identify the type and model of the off-shoe connection 300 based on the accessory information from the off-shoe connection 300.

[0313] When the off-shoe connection 300 is attached, there is a response in the I2C communication and the accessory information can be obtained, and when the off-shoe connection 300 is not attached, it is possible to determine whether the off-shoe connection 300 is attached based on the absence of a response in the I2C communication.

[0314] In S903, when it is determined in S902 that the off-shoe connection 300 is attached, the process proceeds to S904, and when it is determined that the off-shoe connection 300 is not attached, the process proceeds to S907.

[0315] In S904, the camera control circuit A 101 determines whether to permit the operation of the main accessory 200 based on the intermediate accessory operation permission information (first information) which is the D5-D4 data at address 0x05 in the accessory information read in S806. As described above, the intermediate accessory operation permission information is information indicating whether the operation of the main accessory 200 will be permitted in the state where the main accessory 200 is attached to the intermediate accessory. When the operation of the main accessory 200 in the state where the off-shoe connection 300 is attached is permitted, the process proceeds to S905. On the other hand, when the operation of the main accessory 200 in the state where the off-shoe connection 300 is attached is not permitted, the process proceeds to S906.

[0316] In S905, the camera control circuit A 101 ends the process by setting "operation permitted when the off-shoe connection is attached" to the judgment result in this process, and the process proceeds to Figure 14A S808.

[0317] In S906, the camera control circuit A 101 ends the process by setting "operation not permitted when the off-shoe connection is attached" to the judgment result in this process, and the process proceeds to Figure 14A S808.

[0318] When the camera control circuit A 101 determines in S903 that the off-shoe cable 300 is not attached and the process proceeds to S907, the camera control circuit A 101 enables the "normal operation" of the main accessory 200. That is, when the off-shoe cable 300 is not attached, the camera control circuit A 101 provides control different from that in the case where the off-shoe cable 300 is attached. Then, the camera control circuit A 101 ends the process, and the process proceeds to Figure 14A S808.

[0319] Figure 15A and Figure 15B The flowchart of shows the processing to be performed by the accessory control circuit 201 from when the main accessory 200 is attached to the off-shoe cable 300 already attached to the camera 100 until various function operations of the main accessory 200 become available.

[0320] In S1001, 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 main accessory 200 does not include the battery 205, it can be detected that the accessory power supply VACC is turned on as a result of the accessory control circuit 201 being powered and starting to operate. In the case where the main accessory 200 includes the battery 205, the accessory control circuit 201 can monitor the voltage value of the accessory power supply VACC and detect that the accessory power supply VACC is turned on.

[0321] In S1002, the accessory control circuit 201 performs predetermined initial settings, such as setting the operating frequency of the microcomputer, setting the input / output control ports of the microcomputer, initializing the timer function of the microcomputer, and initializing the interrupt function of the microcomputer, etc.

[0322] In S1003, the accessory control circuit 201 determines whether the main accessory 200 is available (operable) in the case where an intermediate accessory is attached, and if the main accessory 200 is available, the process proceeds to S1004, otherwise the process proceeds to S1005. More specifically, in the case where the quality of the signal sent to the camera 100 through the signal line cannot be guaranteed (communication cannot be guaranteed) due to the attachment of the off-shoe cable 300, the accessory control circuit 201 determines that the main accessory 200 is not available. In addition, in the case where the main accessory 200 configured to detect the state of the camera 100 (such as posture detection and motion detection, etc.) cannot accurately detect the state of the camera 100 due to the attachment of the off-shoe cable 300, the accessory control circuit 201 determines that the main accessory 200 is not available. Furthermore, in the case where a specific operation mode is set in which a function cannot be executed due to the attachment of the off-shoe cable 300, the main accessory 200 can be determined to be not available.

[0323] In S1004, the accessory control circuit 201 enables the middle accessory operation permission bit (1 = permitted operation) in the accessory information sent to the camera 100 during the initial communication. Figure 5 shown in the accessory information.

[0324] In S1005, the accessory control circuit 201 disables the middle accessory operation permission bit (0 = not permitted operation) in the accessory information sent to the camera 100 during the initial communication.

[0325] In S1007, the accessory control circuit 201 performs control to change the communication request signal / WAKE to a low level (Lo). Thereby, the accessory control circuit 201 notifies the camera 100 that the initial setup is completed.

[0326] In S1008, in response to the I2C communication from the camera 100, the accessory control circuit 201 sends the 15 - byte accessory information shown in the initial communication to the camera 100. Figure 5 shown in the initial communication to the camera 100.

[0327] When the initial communication in S1008 is completed, in S1009, the accessory control circuit 201 performs control to change the communication request signal / WAKE to a high level (Hi).

[0328] Next, in S1010, the accessory control circuit 201 determines whether a predetermined event has occurred. If no event has occurred, the process returns to S1010 and the accessory control circuit 201 determines again whether an event has occurred. If an event has occurred, the process proceeds to S1011.

[0329] In S1011, the accessory control circuit 201 determines whether the event generated in S1010 is an event that requires SPI communication with the camera 100. If the event requires SPI communication, the process proceeds to S1012; otherwise, the process proceeds to S1013.

[0330] In S1013, the accessory control circuit 201 determines whether the event generated in S1010 is an event that requires I2C communication with the camera 100. If the event requires I2C communication, the process proceeds to S1014; otherwise, the process proceeds to S1015.

[0331] In S1015, the accessory control circuit 201 determines whether the event generated in S1010 is an event that requires control using a function signal. If the event requires control using a function signal, the process proceeds to S1016; otherwise, the process proceeds to S1017.

[0332] In S1017, the accessory control circuit 201 determines whether the event generated in S1010 is an event notified to the camera 100 using the communication request signal / WAKE. If the event is notified to the camera 100 using the communication request signal / WAKE, the flow proceeds to S1018, otherwise the flow proceeds to S1019.

[0333] In S1017, the accessory control circuit 201 stores the communication request factor number to the camera 100 in response to the event generated in S1010 in a volatile memory not shown provided in the main accessory 200, and performs control for changing the communication request signal / WAKE to a low level. Figure 8 The accessory control circuit 201 notifies the camera 100 of intermediate accessory operation permission information, intermediate accessory operation prohibition information, and startup-time intermediate accessory confirmation information as communication request factors according to the operation status of the main accessory 200.

[0334] In S1018, the accessory control circuit 201 performs SPI communication with the camera 100. In the case where the communication request signal / WAKE is at a low level (Lo) when the SPI communication is performed, the communication request signal / WAKE is controlled to change to a high level after the SPI communication. In the case where the main accessory 200 is a microphone device, the SPI communication performed here includes, for example, communication of an instruction to turn on the microphone operation from the camera 100, communication of an instruction to turn off the microphone operation, communication of an instruction to switch the sound directivity of the microphone, communication of an instruction to switch the equalizer function of the microphone, and the like. In the case where the main accessory 200 is a flash device, the SPI communication includes communication for reading setting information of the flash device, communication for notifying the flash device of the setting information, and the like. When the predetermined SPI communication in S1012 is completed, the flow returns to S1010, and the accessory control circuit 201 determines the occurrence of an event again.

[0335] In S1012, S1014, S1016 and S1019, the accessory control circuit 201 performs Figure 12 The same processing is performed at S608, S610, S612 and S615, and then the process returns to S1010.

[0336] Due to the above-described processing using the accessory control circuit 201 , after the main accessory 200 is attached to the camera 100 via the shoe-off cable 300 , the main accessory 200 can perform various functional operations.

[0337] In the above-mentioned embodiments, the electronic device is an imaging device, but the electronic device mentioned in the present invention also includes various electronic devices other than imaging devices.

[0338] Each of the above embodiments can provide an electronic device, a control method of the electronic device, an accessory, and a control method of the accessory, each of which can appropriately handle the main accessory when an intermediate accessory (second accessory) is attached between the electronic device and the main accessory (first accessory).

[0339] Other embodiments

[0340] Embodiments of the present invention can also be implemented by the following method, that is, software (program) that executes the functions of the above embodiments is supplied to a system or device through a network or various storage media, and a method in which a computer or a central processing unit (CPU) or a microprocessing unit (MPU) of the system or device reads and executes the program.

[0341] 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 that can detachably attach accessories, the electronic device including a receiving unit, a processing unit, and an accessory socket portion, to which a first accessory or a second accessory can be attached. Characterized in that when the first accessory is attached to the electronic device via the second accessory attached to the accessory socket portion, the receiving unit receives first information from the first accessory indicating whether to permit an operation of the first accessory attached to the electronic device via the second accessory, and the processing unit controls the operation of the first accessory differently according to the first information.

2. The electronic device according to claim 1, Characterized in that the processing unit restricts the operation of the first accessory when the first information indicates non - permission of the operation.

3. The electronic device according to claim 2, Characterized in that compared with the case where the first accessory is attached to the electronic device without the intervention of the second accessory, when the first information indicates non - permission of the operation, the processing unit restricts the operation of the first accessory more.

4. The electronic device according to claim 2, Characterized in that the electronic device is configured to supply power to the first accessory, wherein, when the first information indicates non - permission of the operation, the processing unit disconnects the power supply to the first accessory.

5. The electronic device according to claim 2, Characterized in that when the first information indicates non - permission of the operation, the processing unit notifies the user that the operation of the first accessory is restricted.

6. The electronic device according to claim 1, Characterized in that when the first accessory is attached to the electronic device via the second accessory, the receiving unit receives second information from the first accessory indicating whether it is necessary to confirm the presence or absence of the second accessory, and when the second information indicates the need for confirmation and the attachment of the second accessory is confirmed, the first information is received from the first accessory.

7. The electronic device according to claim 1, Characterized in that the receiving unit receives accessory information for identifying each accessory stored in the respective memories of the first accessory and the second accessory via the same serial communication line, as information related to different memory addresses.

8. The electronic device according to claim 1, Characterized in that the processing unit controls the first accessory differently between the case where the first accessory is attached to the electronic device via the second accessory and the case where the first accessory is attached to the electronic device without the intervention of the second accessory.

9. The electronic device according to claim 1, further including a setting unit configured to enable the user to permit the use of the first accessory, wherein when the first information indicates non - permission of the operation, when the user permits the use of the first accessory through the setting unit, the processing unit controls the operation of the first accessory.

10. An accessory that is detachably attachable to an electronic device or an intermediate accessory, the accessory including an accessory processing unit configured to communicate with the electronic device. Characterized in that the accessory is attached to an accessory socket portion of the electronic device, and when the accessory is attached to the electronic device via the intermediate accessory, the accessory processing unit sends first information indicating whether to permit an operation of the accessory attached to the electronic device via the intermediate accessory to the electronic device.

11. The accessory according to claim 10, Characterized in that when communication with the electronic device cannot be ensured, the function of the accessory cannot be executed, or an operation mode for disabling a function in the accessory is set due to the accessory being attached to the electronic device via the intermediate accessory, the accessory processing unit sends the first information indicating non - permission of the operation.

12. The accessory according to claim 10, Characterized in that when the accessory is attached to the electronic device via the intermediate accessory, the accessory processing unit sends second information indicating whether it is necessary to confirm the presence or absence of the intermediate accessory to the electronic device, wherein, based on the second information indicating the need for confirmation, the accessory processing unit sends the first information to the electronic device that has confirmed the attachment of the intermediate accessory.

13. A control method for an electronic device that is detachably attachable with an accessory, the control method comprising the following steps: when a first accessory is attached to the electronic device via a second accessory attached to an accessory socket portion of the electronic device: receiving first information indicating whether to permit an operation of the first accessory attached to the electronic device via the second accessory from the first accessory, and performing different controls on the operation of the first accessory according to the first information, wherein either the first accessory or the second accessory is attachable to the accessory socket portion.

14. A control method for an accessory that is detachably attachable to an accessory socket portion of an electronic device or an intermediate accessory, the control method comprising the following steps: sending first information indicating whether to permit an operation of the accessory attached to the electronic device via the intermediate accessory to the electronic device.

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