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代码说明：

说明：  本系统以单片机AT89C51为主体,由芯片插座、独立按键、74HC573驱动8位数码管显示、5V直流电源控制模块等组成。根据数字集成芯片的引脚特性以及集成芯片的真值表编写检测程序。该系统能完成14脚以内常用TTL74系列数字集成芯片的功能测试。(This system is the main body of the single-chip microcomputer AT89C51, the chip socket, independent buttons, 74HC573 Driver 8 digital control, 5V DC power control module and so on. According to the characteristics of the digital chip and the chip s true value, the program is written in the chip.. The system can complete the functional test of the TTL74 series digital IC chip in 14 feet.)