CATHODE RAY TUBE DISPLAY SYSTEM

摘要

A cathode ray tube display system includes a refresh memory (14) storing data to be displayed and normally accessed by CRT controller (12), but in response to a request signal, accessible by a microprocessor (10). In response to such a request signal, a control unit (32) switches a multiplexer (16) to pass address signals from the microprocessor (10) to the refresh memory (14) and further provides an inhibit signal to a parallel-to-serial convertor (26) in the CRT video drive to prevent any data read out from the memory (14) from being displayed. The CRT has a long persistance time such that flashing or flickering of the display is avoided.