DATA TRANSMISSION METHOD, DATA TRANSMISSION SYSTEM AND MEDIUM RECORDING PROGRAM TO EXECUTE THIS METHOD

摘要

PROBLEM TO BE SOLVED: To provide a data transmission method by which an asynchronous.half-duplex communication system quickly restores to a usual frame exchange time in the case that a communication error is normally recovered after the occurrence of the communication error in a communication line. SOLUTION: A primary station stores a data transmission request (RdataReq 104) that is first generated during a communication error (a state that data 103 are stored in a re-transmission buffer) into a transmission storage buffer. Then the primary station aborts both K data transmission request (RdataReq 105) secondarily generated and a data transmission request (RdataReq 106) generated in the third during the communication error. Then the primary station can transmit data in a timing of a data transmission request (RdataReq 107) when receiving data 206 sent from a secondary station next. Thus, the primary station can send data while keeping a normal frame exchange time T after the data transmission request (RdataReq 107).