摘要:
彩色电视测试卡是一种以直观方式评价彩色电视接收机质量的测试信号.我们以Z80微处理机为核心,组成了彩色电视同步信号和彩色测试卡发生装置。将微机技术、数字技术和模拟技术结合在一起,并发挥微机软件的作用,使原先需要使用大量组合和时序逻辑电路才能产生的各种信号(如复合同步、复合消隐等同步信号和圆、彩条、灰条、时钟等测试卡信号)尽可能地用软件直接产生或用软件简化控制电路,通过以软代硬来实现整个系统的小型化、高可靠、低成本。所有软件均固化于EPROM中,通过改变软件即可方便地改变测试卡图形的排列和图案的内容而不必大量地改变硬件结构。同样,只需修改软件中同步信号形成程序,便可按需要产生各种非广播电视标准的同步信号和测试卡。
Abstract:
Test-card for colour TV is a signal widely used to evaluate visually the quality of a TV set. Based on the microprocessor Z-80 a test-card generator for colour TV with synchronizing is realized. By taking advantage of microprocessor programming, the techniques of computer, digital and IC are combined to simplify greatly the system circuits which originally need a large quantity of logical gates. Now, the functions of control and the generation of signal, such as compound synchronous signal, compoud blanking signal, etc, are realized with the help of CPU programming to get the advantages of low cost, high reliability and small size. All system programs are stored in EPROMs and thus any wanted changes in the pattern of test card can be conveniently realized by changing programs, and it is not necessary to change the whole configuration of the hardware circuits. The system can also be transferred into different types of non-standard TV synchronizers and test-card generators by only changing the programs.