CONTROL METHOD FOR TRANSMISSION DATA QUANTITY IN LAN

PURPOSE:To circulate a token within a specified time without providing a timer by adopting the constitution such that an item of a transmission permissible data length is provided in a token frame and the circulation of the token is devised based on the data length. CONSTITUTION:When the processing is started and a token holding station is an initial set station 1, the initial value of the newest transmission permission length data is set in the frame of the station 1. When the transmission data exists in the next station, the data length sent this time is subtracted from the transmission permission data length in the token frame and when the result is '0' or over, the subtracted transmission data length is set in the token frame and sent. When the transmission is finished normally, the token takes over the next station. The token is circulated sequentially in the logic ring and when the token is circulated and returned to the No.1 station, the initial value of the new transmission permission data is set in the token frame and the above operation is repeated.