基于51的串口计算器程序

#include #include unsigned char tmp; unsigned char data1 = 0; unsigned int num1 = 0,num2 = 0,num3 = 0,fu = 0; int q[100] = {0}; int printf_flag = 0; int a = 0; int c = 0; void send_char(unsigned char txd); void send(unsigned int u); void main() { // EA = 1; //总开关 // ES = 1; //IE寄存器 通信开关 SCON = 0x50; // 设定串行口工作方式 0101 0000 工作方式1 TMOD = 0x20; // 定时器1工作于8位自动重载模式, 用于产生波特率 TH1 = 0xFD; // 波特率9600 TL1 = 0xFD; PCON = 0x00; // 波特率不倍增 TR1 = 1; // 启动定时器1 while(1) { if(RI == 1) // 是否有数据到来 { RI = 0; data1 = SBUF; //P1 = data1; // 数据传送到P0口 // send_char(data1); // 回传接收到的数据 if(( data1>='0') && (data1<='9')) { num1 = 10*num1+(data1 -'0'); } else if(data1 == '+'||data1 =='-'||data1 == '*'|| data1 == '/') { fu = data1; num2 = num1; num1 = 0; } else if(data1 == '='&&fu; == '+')// { num3 = num1+num2; printf_flag = 1; } else if(data1 == '='&&fu; == '-')// &&fu; == '-' { num3 = num2-num1; printf_flag = 1; } else if(data1 == '='&&fu; == '*')//&&fu; == '*' { num3 = num1*num2; printf_flag = 1; } else if(data1 == '='&&fu; == '/')// '&&fu; == '/' { num3 = num1/num2; printf_flag = 1;