| 摘要 |
PURPOSE:To prevent the double transmission of the same data and the omission of a data block in a retrial mode by giving data blocks to the data blocks which are transferred to a main memory respectively and controlling these data blocks according to the data numbers. CONSTITUTION:A data processing system consists of a central processor 1, a main memory 2, a channel 3, a communication controller 4 and a MODEM 5. The data numbers are given to the data blocks included in an input buffer 21 of the controller 4. Then the data number of a message transferred normally is stored in a microprocessor 13 as the latest data number, and the retrial start data number serving as the number to be transferred again in a retrial mode is given to the controller 4. Thus a microprocessor 23 of the controller 4 performs the control based on the received retrial start data number so that the messages having the corresponding data numbers in the buffer 21 are transferred successively again. |
