| 摘要 |
PURPOSE:To unnecessitate an external device for supplying compulsory clock by providing a communication termination setting circuit where the interruption request corresponding to a communication termination is compulsorily generated when the count value of a counter is below a set value and a reading bus. CONSTITUTION:This transmitting device is provided with a clock selector 1, a clock control circuit 2, a shift register 3, a counter 4, an interruption signal generation circuit 5 and a bus 8 in the same way as a conventional device. The transmitting device is further provided with a communication termination setting circuit 6 where the count value of the counter 4 is below (n) to be the set value corresponding to the bit length of the communication data D that the count value of the counter 4 preliminarily sets and a matching signal Q for compulsorily generating the interruption request RI corresponding to the communication termination by continuously supplying an external clock CKE for more than fixed time is supplied and an OR circuit 7 0Ring an overflow signal F and a matching signal Q and a bus for reading the count value of the counter 4 to confirm an effective data length. Therefore, also at the time of receiving data of the length of an unknown bit, a communication termination interruption can be surely generated. |
