本文介绍了AT89C2051单片机的性能和特点，并在分析了超声波测距原理的基本系统框图。该设计系统经校正后，其测量精度可达0.1米-This paper introduces the AT89C2051 MCU performance and features, and the analysis of the basic principle of ultrasonic distance measurement system block diagram. The design system has been corrected, the measurement accuracy up to 0.1 meters
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