本报告介绍了基于AT89S52单片机为核心的、以AD0809数模转换芯片采样、以1602液晶屏显示的具有电压测量功能的具有一定精度的数字电压表。在实现基础功能要求之上扩展了串口通讯、时钟功能、高压报警、短路测试、电阻测量、交流电压峰峰值和周期测试等功能，使系统达到了良好的设计效果和要求。-

This report describes on AT89S52 microcontroller as the core, to AD0809 DAC chip sampling, digital voltmeter with a certain precision voltage measurement function has LCD display with 1602. On the basis of the functional requirements to achieve extended serial communication, clock function, high pressure alarm, short circuit testing, resistance measurement, AC voltage peak value and cycle testing and other functions, allowing the system to achieve a good performance and design requirements.