说明：   MCS-51单片机ASM语言的U盘文件读写示例程序,支持89C2051,89C51,89C52等单片机，本程序演示字节读写,用于将ADC模数采集的数据添加到U盘或者SD卡文件MY_ADC.TXT中。
(MCS-51 microcontroller ASM language U disk file reading and writing examples procedures, support 89C2051,89C51,89C52 chip, this procedure demonstration byte read and write for the ADC module, data is added to the U disk or SD card file MY_ADC.TXT.)