CONTROL SYSTEM FOR COMMUNICATION DATA TRANSFER

摘要

PURPOSE:To attain the control of data transfer without providing a special control mechanism and logic by adding a dummy byte in a transmission packet fed to a data terminal by a central processing unit at the data transfer from the central processing unit to a communication device. CONSTITUTION:The central processing unit CC having a main storage device MM is connected to a data terminal device DTE via a channel device MXCH and a communication device FCTE. The central controller CC sets a flag E1 representing that the final byte of the header is a dummy and a flag E2 representing the final byte of the data section is a dummy as well as a transmission packet length Ls to the interface section reserved in a transmission header area SHA. A transmission buffer area SBF controls the transmission of data terminal depending on the elimination/non-elimination of the dummy byte in response to the flag included in a command from the CC. Then, the control of data transfer is attained easily.