用单片机设计的测速表源程序。测量转速，使用霍尔传感器，被测轴安装有12只磁钢，即转轴每转一周，产生12个脉冲，要求将转速值（转/分）显示在数码管上。-The speed table with a single-chip design source. Measurement speed, the use of Hall sensors, the measured shaft with 12 magnets, one revolution of the shaft each produce 12 pulses, requires speed (r/min) displayed on the digital pipe.