视频字符的显示原理是将字符点阵信号与原始视频信号叠加.在视频图像上实时叠加字符,可以及时将关键的数据和工作状态显示出来,既醒目又直观,因此视频字符显示技术得到了广泛的应用.文中介绍一种视频字符显示方法,该方法利用CPLD(Complex Programmable Logic Device,复杂可编程逻辑器件)与单片机实现视频字符的显示功能,即通过监视器实时显示所需观测的字符信息.实验证明用这种方法设计的电路性能稳定且易于维护.

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.