采用4×4键盘，16个键依次对应0～9、“+”、“-”、“×”、“÷”、“ ”和清除键。可以进行小于255的数的加减乘除运算，并可连续运算。当键入值大于255时，将自动清零，可以重新输入。反转法扫描键盘，串行口数据输出，74ls164驱动数码管显示 P1口为扫按键特征码输入端 P3.0,P3.1为串行口数据输出端连接串行静态显示模块的DIN、CLK端。-Using 4 4 keyboard, 16 key corresponding to 0 ~ 9+ in turn-　 and clear key Can be less than 255 the number of operations of addition, subtraction, multiplication, and division, and continuous operation When typing values greater than 255, will be automatically reset, you can re-enter the inversion method of scanning the keyboard, serial data output, 74 ls164 drive digital tube display P1 mouth to sweep the key signature input P3.0, P3.1 for serial data output connection serial static display module DIN CLK