SH79F083 芯片的原厂例程. 内含有定时器,中断,IO操作. SOP20.-The SH79F083 chip of the original factory routine. Contains a timer, interrupt, IO operation. SOP20.

三个按键输入，一个三位数码输出，三个LED输出(Three key presses, a digital output, three three LED output)