《自动切换量程的电压表》 这是一个基于51单片机量程可以自动切换的数字电压表。内附完整的C语言编程和电路仿真图。-" Automatic switching voltage range table" This is a single chip based on 51 on 0-200mv, 200mv-2v, 2v-20v of the three ranges can automatically switch the digital voltmeter. Containi