Camera accessory with data producer

A camera accessory capable of transmitting data to a camera comprising:

• means for generating a digital code in response to a manual operation to select among various values for information to be set for photography;
• a read only memory for storing various data at a plurality of address, respectively, the data including data corresponding to said values for the information, respectively;
• means for receiving a digital signal from said camera;
• means responsive to said digital code and said digital signal for controlling a data transmission from said camera accessory to said camera, said controlling means including means for designating an address, at which a data corresponding to a specific value selected by the manual operation is stored, to transmit said data stored in the designated address to said camera;
• and
• a digital display for indicating, at said camera accessory, the specific value for the information corresponding to said data to be transmitted to the camera.

An interchangeable lens barrel capable of transmitting data to a camera comprising:

• means for generating a digital code in response to a manual operation to select among various values for information to be set for photography, said digital code being indicative of a specific value for the information selected by the manual operation;
• a digital display responsive to data corresponding to said digital code for indicating, at said interchangeable lens barrel, the specific value for the information selected by the manual operation;
• and
• means for transmitting to said camera data corresponding to said digital code representative of the specific value for the information.

A camera accessory that effects the operation of a camera body during photography by inputting certain informational data about the accessory to the camera body for corresponding adjustment of the camera body operation, comprising:

• an accessory housing member;
• a read only memory having a plurality of distinct groups of data at a plurality of addresses, each group of data relating to an accessory compatible with the camera body including distinct groups of data that are not relevant to the specific accessory housing member supporting the read only memory;
• means for identifying the camera accessory to the camera body, and
• means for controlling a transmission of data from the camera accessory to the camera body in response to the means for identification so that only that distinct group of data relevant to the specific accessory is operatively transmitted to the camera body, whereby the read only memory can serve as a common element to not only the specific accessory but to other compatible accessories.