Accessory apparatus and imaging apparatus

An imaging apparatus to which an accessory apparatus is connectable along with an interchangeable lens apparatus, the accessory apparatus including an operation member allowing an operation by a user, the imaging apparatus comprising:

• a first communication line configured to communicate with the accessory apparatus and a second communication line, which is different from the first communication line, configured to communicate with the accessory apparatus;
• at least one processor;
• and
• at least one memory coupled to the at least one processor storing instructions that, when executed by the at least one processor, cause the at least one processor to function as a communication control unit configured,
• in response to transmission of first data that is transmitted via the first communication line in response to a change in a signal level of the second communication line from a first signal level to a second signal level different from the first signal level, to transmit, after reception of second data corresponding to a start of the operation on the operation member, third data that corresponds to a transmission request for fourth data corresponding to an operation amount of the operation member, and
• in response to the change in the signal level of the second communication line from the first signal level to the second signal level, to transmit the third data, and
• wherein the communication control unit is configured to receive the fourth data after receiving the second data, and transmit the third data after transmitting the first data.

A control method of an accessory apparatus connectable to an imaging apparatus, the accessory apparatus including an operation member allowing an operation by a user, a first communication line configured to communicate with the imaging apparatus, and a second communication line, which is different from the first communication line, configured to communicate with the imaging apparatus, the control method comprising:

• controlling, in response to detecting the operation on the operation member, change of a signal level of the second communication line from a first signal level to a second signal level different from the first signal level,
• wherein in the controlling,
• in response to reception of first data that is transmitted via the first communication line in response to the change in the signal level of the second communication line to the second signal level, second data corresponding to a start of the operation on the operation member is transmitted via the first communication line, and
• in response to reception, via the first communication line, third data that corresponds to a transmission request for fourth data corresponding to an operation amount of the operation member, the fourth data is transmitted, and
• wherein in the controlling, the fourth data is transmitted after the second data is transmitted, and the third data is received after the first data is received.

A control method of an imaging apparatus to which an accessory apparatus is connectable along with an interchangeable lens apparatus, the accessory apparatus including an operation member allowing an operation by a user, the imaging apparatus including a first communication line configured to communicate with the accessory apparatus and a second communication line, which is different from the first communication line, configured to communicate with the accessory apparatus, the control method comprising:

• providing control such that:
• in response to transmission of first data that is transmitted via the first communication line in response to a change in a signal level of the second communication line from a first signal level to a second signal level different from the first signal level, after reception of second data corresponding to a start of the operation on the operation member, third data that corresponds to a transmission request for fourth data corresponding to an operation amount of the operation member is transmitted;
• and
• in response to the change in the signal level of the second communication line from the first signal level to the second signal level, the third data is transmitted,
• wherein in the control, the fourth data is received after the second data is received, and the third data is transmitted after the first data is transmitted.