Imaging apparatus, accessory device, storage medium, and imaging system

An imaging apparatus, to which an accessory device is detachably mounted and which performs image capturing in synchronization with a vertical synchronization signal, the imaging apparatus comprising:

• a control unit configured to perform communication with the accessory device in synchronization with the vertical synchronization signal,
• wherein the control unit transmits, to the accessory device, a request command for requesting transmission of data from the accessory device to the imaging apparatus to cause the accessory device to transmit data corresponding to the request command and is capable of transmitting, to toe accessory device, a plurality of request commands each corresponding to the request command within one period of the vertical synchronization signal, and
• wherein the control unit adds, to a request command which is transmitted at predetermined timing within one period of the vertical synchronization signal, information indicating the request command which is transmitted at the predetermined timing and transmits the request command with the information added thereto to the accessory device.

An accessory device, which is detachably mounted to an imaging apparatus configured to perform image capturing in synchronization with a vertical synchronization signal, the accessory device comprising:

• a control unit configured to perform communication with the imaging apparatus in synchronization with the vertical synchronization signal,
• wherein, in response to receiving a request command for requesting transmission of data from the accessory device to the imaging apparatus, which is transmitted from the imaging apparatus, the control unit transmits data to the imaging apparatus, and is capable of receiving a plurality of request commands each corresponding to the request command from the imaging apparatus within one period of the vertical synchronization signal, and
• wherein the request command includes a plurality of types of commands and the control unit first receives a previously-determined specific request command of the plurality of types of commands within one period of the vertical synchronization signal.

An accessory device, which is detachably mounted to an imaging apparatus configured to perform image capturing in synchronization with a vertical synchronization signal, the accessory device comprising:

• a control unit configured to perform communication with the imaging apparatus in synchronization with the vertical synchronization signal,
• wherein, in response to receiving a request command for requesting transmission of data from the accessory device to the imaging apparatus, which is transmitted from the imaging apparatus, the control unit transmits data to the imaging apparatus, and is capable of receiving a plurality of request commands each corresponding to the request command from the imaging apparatus within one period of the vertical synchronization signal, and
• wherein the control unit first receives a request command to which information indicating a request command which is transmitted at predetermined timing within one period of the vertical synchronization signal is added, within one period of the vertical synchronization signal.

A computer-readable storage medium storing computer-executable instructions which, when executed by a computer of an imaging apparatus, to which an accessory device is detachably mounted, which performs image capturing synchronization with a vertical synchronization signal, and which is capable of transmitting, to the accessory device, a plurality of types of request commands each for requesting transmission of data from the accessory device to the imaging apparatus within one period of the vertical synchronization signal in synchronization with the vertical synchronization signal, cause the computer to perform a method comprising:

• transmitting a request command selected from among the plurality of types of request commands to the accessory device to cause the accessory device to transmit data corresponding to the request command;
• and
• transmitting a previously-determined specific request command of the plurality of types of request commands at predetermined timing within one period of the vertical synchronization signal.

A computer-readable storage medium storing computer-executable instructions which, when executed by a computer of an imaging apparatus, to which an accessory device is detachably mounted, which performs image capturing in synchronization with a vertical synchronization signal, and which is capable of transmitting, to the accessory device, a plurality of types of request commands each for requesting transmission of data from the accessory device to the imaging apparatus within one period of the vertical synchronization signal in synchronization with the vertical synchronization signal, cause the computer to perform a method comprising:

• first transmitting a request command to which information indicating a request command which is transmitted at predetermined timing within one period of the vertical synchronization signal is added, within one period of the vertical synchronization signal.

A computer-readable storage medium storing computer-executable instructions which, when executed by a computer of an accessory device, which is detachably mounted to an imaging apparatus configured to perform image capturing in synchronization with a vertical synchronization signal and which is capable of receiving, from the imaging apparatus, a plurality of types of request commands each for requesting transmission of data from the accessory device to the imaging apparatus within one period of the vertical synchronization signal in synchronization with the vertical synchronization signal, cause the computer to perform a method comprising:

• first receiving a request command to which information indicating a request command which is first transmitted within one period of the vertical synchronization signal is added, within one period of the vertical synchronization signal.