Data exchange system for computer and adapted terminal - has buffer memory from which data are separated for fast and slow processing in computer via control circuit and microcomputer respectively

摘要

An interface, having a direct access memory control circuit (3), RAMs (4,5,11) and two microcomputers (6,8) is connected between the screen output (2) and the computer terminals. The interface also has adaptors (10) corresponding to each terminal to which it is connected. Each interface is tested by the memory control circuit (3) and the data obtained are recorded in a buffer memory (4) to separate the rapid processing data from the slower processing type. The rapid access data are transmitted between the RAM (4) and the computer (1) via the central circuit (3). The slower processing data are assigned to one of the microcomputers (6) for processing and a screen is simulated to ensure data exchange between the computer and the terminals in accordance with different transmission and control procedures. When the computer (1) transmits a message, it is transferred to one of the RAM's (4,5,11). When they are filled, the data in the microcomputer (6) are decoded to recognise which terminal is addressed. The appropriate commands are introduced in the other microcomputer (8).