Patent ID: 8102430

Claim:
An interchangeable lens which can communicate with an associated camera body when said interchangeable lens is detachably attached to the camera body to exchange data of said interchangeable lens, said interchangeable lens comprising: an interface logic IC via which said interchangeable lens communicates with the camera body, said interface logic IC comprises a plurality of terminals that serve as at least one group of fixed data set pins and another plurality of terminals through which said interchangeable lens communicates with the camera body, the another plurality of terminals being distinct from said plurality of terminals; and a memory which is independent of said interface logic IC, is connected to said interface logic IC, and stores said data of said interchangeable lens, wherein fixed data of said interchangeable lens is allocated to a predetermined number of bytes of data which is sent from said interchangeable lens to the camera body by said at least one group of fixed data set-pins to which levels corresponding to said fixed data are set, and wherein, in communication with the camera body for a predetermined number of bytes thereof in an initial stage of a communication, said interface logic IC reads said fixed data which is set by said group of fixed data set pins, sends said read fixed data to the camera body, and outputs data to said memory, said output data used for reading out data of said interchangeable lens from said memory and sends, subsequent to said predetermined number of bytes, said data of said interchangeable lens which is read from said memory to said camera body.