Realization of video Character Display by Using CPLD

The principle of displaying a video character is that a character dot matrix signal is superimposed upon an original video signal. The key data and working state can be strikingly displayed on the monitor by superimposing some characters upon a video picture. Therefore, the technology of video character display is widely used. In this paper, a method of video character display , which uses CPLD along with a single chip microcomputer to realize the function of video character display and to show the realtime characters required to be viewed on the monitor,is presented. The experiments indicates that the circuit designed with this method is characterized by the stable performance and easy maintenance.