Accessory apparatus and imaging apparatus

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

• a first communication line configured to communicate with the accessary apparatus and a second communication line, which is different from the first communication line, configured to communicate with the accessary apparatus;
• and
• a communication control unit configured,
• 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 second data via the first communication line,
• in response to the transmission of the second data via the first communication line, to receive first data via the first communication line, and
• to receive third data in response to transmission of fourth data via the first communication line,
• wherein the communication control unit receives the third data after receiving the first data, and transmits the fourth data after transmitting the second data,
• wherein the third data changes according to an operation amount of the operation member, while the first data does not change regardless of the operation amount, and
• wherein at least one processor or circuit is configured to perform a function of at least one of the units.

A control method of an accessory apparatus mountable on an imaging apparatus, the accessory apparatus including an operation member allowing an operation by a user, a first communication line for performing communication with the imaging apparatus, and a second communication line, different from the first communication line, configured to perform communication with the imaging apparatus, the control method comprising:

• changing, in response to detecting the operation on the operation member, a signal level of the second communication line from a first signal level to a second signal level different from the first signal level,
• performing control to transmit first data in response to reception of second data via the first communication line that is transmitted via the first communication line in response to the change of the signal level of the second communication line to the second signal level, and
• transmitting third data in response to receiving fourth data via the first communication line,
• wherein the third data is transmitted after transmitting the first data, and the fourth data is received after receiving the second data, and
• wherein the third data changes according to an operation amount of the operation member, while the first data does not change regardless of the operation amount.

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

• transmitting, 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, second data via the first communication line,
• receiving, in response to the transmission of the second data via the first communication line, first data via the first communication line, and
• receiving third data in response to transmission of fourth data via the first communication line,
• wherein the communication control unit receives the third data after receiving the first data, and transmits the fourth data after transmitting the second data, and
• wherein the third data changes according to an operation amount of the operation member, while the first data does not change regardless of the operation amount.