Camera accessory, camera body and camera system

A camera accessory to be detachably mounted at a camera body that includes a first body contact point and a second body contact point and detects disengagement of the camera accessory when the second body contact point sustains a signal level corresponding to a first truth value continuously over a length of time equal to or greater than a predetermined time length, the camera accessory comprising:

• a mounting device to be detachably mounted at the camera body;
• a first accessory contact point that is connected with the first body contact point while the camera accessory is engaged with the camera body by the mounting device and to which an information communication operation with the camera body is executed;
• a second accessory contact point that is connected with the second body contact point while the camera accessory is engaged with the camera body by the mounting device so as to allow a signal that has a level corresponding to the first truth value to be output to the camera body during a time period in which the information communication operation via the first accessory contact point is disallowed;
• and
• an accessory-side communication control device that executes the information communication operation with the camera body via the first accessory contact point, wherein:
• the accessory-side communication control device executes control so as to ensure that a time length during which the signal that has a level corresponding to the first truth value continues to be output at the second accessory contact point is less than the predetermined time length while the mounting device is mounted at the camera body.

A camera accessory to be detachably mounted at a camera body that includes a first body contact point and a second body contact point and detects disengagement of the camera accessory when the second body contact point sustains a signal level corresponding to a first truth value continuously over a length of time equal to or greater than a predetermined time length, the camera accessory comprising:

• a mounting device to be detachably mounted at the camera body;
• an accessory-side communication control device that executes an information communication operation with the camera body while the camera accessory is engaged with the camera body by the mounting device;
• a first accessory contact point that is connected with the first body contact point while the camera accessory is engaged with the camera body by the mounting device so as to receive an operating voltage supplied from the camera body;
• a second accessory contact point that is connected with the second body contact point while the camera accessory is engaged with the camera body by the mounting device so as to allow a signal that has a level corresponding to the first truth value to be output to the camera body during a time period in which the information communication operation is disallowed, wherein:
• the accessory-side communication control device executes control so as to ensure that a time length during which the signal that has a level corresponding to the first truth value continues to be output at the second accessory contact point is less than the predetermined time length while the operating voltage is supplied from the camera body via the first accessory contact point.