本文介绍了利用AT89C51单片机组成的一个简单测压显示模块电路,并详细介绍了其接口和应用。 关键字:单片机;A/D转换器;串行接口 Abstract: In this paper, we introduce a simple circuit module for voltage measuring and displaying, which main consists of MCU AT89C51, and discuss its interface and application in detail. Keywords: MCU; ADC0809 ; Serial interface