A MICROPROCESSOR-BASED GENERATOR OF SYNCHRONIZING SIGNAL AND TEST-CARD FOR COLOUR TV

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.