本程序在单片机C8051F020上将直流电动机当前的转速值在七段数码管上显示出来，在电机的可控范围内控制电机转速等于预设值。运行速度设置为2000转/分，电机启动经过若干秒后，将以设定的速度运行。为了达到调速的效果，本程序使用阵列键盘更改运行速度。-This procedure will be in the single-chip C8051F020 DC motor speed value of the current Seven-Segment LED display out of control in the framework of motor control motor speed equal to the default. Speed set to 2000 r/min, electric start, after a number of seconds later, the speed will be set up to run. In order to achieve the effect of speed, the program uses arrays to change the running speed of the keyboard.