说明：  TLC549串行模数转换，将转换后的数据通过I2C 7290驱动数码管输出。 采用keil 开发，用汇编语言写的程序；
(TLC549 serial analog-to-digital conversion, data will be converted through a digital I2C 7290-driven output tube. Using keil development, written in assembly language with procedures )