熟悉PIC单片机A/D转换的C语言用法，选择RAO做为模拟输入通道，连续转换4次再求平均值做为转换结果，最后结构只取低8位，结果送数码管的低3位显示-Familiar with the PIC microcontroller A/D conversion of the C language usage, select the RAO as the analog input channel, continuous conversion as 4 times and then averaging conversion results, the final structure obtained only the lower 8 bits, the result sent to the low 3 LED display