| 摘要 |
PURPOSE:To transmit and receive a lot of data to and from a central computer by using a transmitting and receiving buffer request flag and a busy flag which are turned on and off by a program of a terminal control device. CONSTITUTION:In a terminal control device 1, in case when a data of a file 2 is transmitted to a central computer 3 by a data processing program 8, a transmitting buffer request flag is turned on and the data is transferred to a transmission and reception combined buffer 9. Subsequently, the data is sent out to the computer 3 after waiting for a polling signal from the computer 3 through an MODEM4 and a communication line 5. Thereafter, a selection signal of a transmission requet is received from the computer 3. When a buffer busy flag is off, the terminal control device 1 turns on a receiving buffer request flag and receives the data. Also, when the busy flag is on, the bush flag is turned off by turning on a transmitting buffer release request flag, and the transmission and reception combined buffer 9 is set to an unused state. |
