介绍了利用微处理机控制单元(MCU microprocessor control unit) 控制的超声测距仪的原理:由MCU 控制时间计数,计算超声波自发射至接收的往返时间,从而得到实测距离。给出了系统构成、电路原理及程序设计。并且在数据处理中采用了温度补偿和修正量的调整。此系统具有易控制、工作可靠、测距准确度高和流程清晰等优点。-Abstract : Principle and structure of ultrasonic distance measurement instrument by master of MCU are intro2 duced. With the control of MCU to operate the time2keeping ,distance from target to original point is gained using product with the time of ultrasonic transmitting both to the target and reflecting back and the speed of ultrasonic which transmits in the air. And system structure ,circuit philosophy and programming are also specified. In the process of data , temperature compensation and adjustment of amendment ammount are used , so the instrument system has features : ease of control , stability of operation , highness of precision and distinctness of programme process ,etc.

Key words : microprocessor control unit (MCU)　 ultrasonic sensor　 distance measurement　 temperature com2 pensation