| 摘要 |
PROBLEM TO BE SOLVED: To provide an image forming apparatus capable of reducing operation delays due to communication abnormality without increasing the amount of communication data.SOLUTION: Upon notification of communication abnormality from a compound machine body 101, a data creation unit 301 of an accessory device 180 creates predetermined length of serial data including information indicating a detection state of a sensor corresponding to the subsequent communication timing and counter values held in a counter value holding unit 305. A timing start point specifying unit 314, when the serial data received from the accessory device 180 includes counter values, specifies a timing start point corresponding to a change in state of the paper feeding sensor 183 on the basis of the information indicating the detection state of the paper feeding sensor 183 and the counter values included in the serial data, and a correspondence relationship between a first free-run counter 304 and a second free-run counter 317. An operation control unit 315, when a predetermined time elapses from the specified timing start point, drives a conveyance roller 164. |
