PURPOSE: To reduce the overhead of a central processing unit by informing the end of a test to a communication control equipment in a prescribed after a start-stop type communication control unit receives a control code automatically so as to reduce the number of times of interruption to the central processing unit.

CONSTITUTION: The central processing unit 1 designates a control code from a start-stop terminal equipment 30 to a control code storage circuit 23 and designates a time of data transmission from a start-stop terminal equipment 30 to a timer circuit 26. Thus, the start-stop communication control unit 20 detects the end of text automatically and informs it to the communication control equipment 10, then the communication control unit 10 recognizes the end of text. Thus, the interruption to the central processing unit is reduced the overhead of the central processing unit is decreased.