Keil uVision5 1.4寸屏幕的简易计算器

以下是使用Keil uVision5编写的简易计算器代码，可以在1.4寸屏幕上显示数字和运算符，并支持加、减、乘、除四种基本运算：

#include <reg52.h>

#define uchar unsigned char
#define uint unsigned int

sbit RS = P2^0;
sbit RW = P2^1;
sbit EN = P2^2;

uchar num1[5] = {0};
uchar num2[5] = {0};
uchar result[5] = {0};
uchar operator = 0;

void delay(uint i)
{
    while(i--);
}

void writeCmd(uchar cmd)
{
    RS = 0;
    RW = 0;
    P0 = cmd;
    EN = 1;
    delay(100);
    EN = 0;
}

void writeData(uchar dat)
{
    RS = 1;
    RW = 0;
    P0 = dat;
    EN = 1;
    delay(100);
    EN = 0;
}

void initLCD()
{
    writeCmd(0x38);
    writeCmd(0x0c);
    writeCmd(0x06);
    writeCmd(0x01);
}

void clearLCD()
{
    writeCmd(0x01);
}

void writeStr(uchar x, uchar y, uchar *str)
{
    uchar i;
    if(y == 0)
    {
        writeCmd(0x80 + x);
    }
    else
    {
        writeCmd(0xc0 + x);
    }
    for(i = 0; str[i] != '\0'; i++)
    {
        writeData(str[i]);
    }
}

void readNum1()
{
    uchar i, j = 0;
    clearLCD();
    writeStr(0, 0, "Num1:");
    while(1)
    {
        if(j > 4)
        {
            break;
        }
        if(P3 != 0xff)
        {
            num1[j] = P3;
            j++;
            delay(1000);
            while(P3 != 0xff);
        }
        writeStr(6, 0, num1);
    }
}

void readNum2()
{
    uchar i, j = 0;
    clearLCD();
    writeStr(0, 0, "Num2:");
    while(1)
    {
        if(j > 4)
        {
            break;
        }
        if(P3 != 0xff)
        {
            num2[j] = P3;
            j++;
            delay(1000);
            while(P3 != 0xff);
        }
        writeStr(6, 0, num2);
    }
}

void readOp()
{
    clearLCD();
    writeStr(0, 0, "Op:");
    while(1)
    {
        if(P3 == 0xfd)
        {
            operator = '+';
            break;
        }
        else if(P3 == 0xfb)
        {
            operator = '-';
            break;
        }
        else if(P3 == 0xf7)
        {
            operator = '*';
            break;
        }
        else if(P3 == 0xef)
        {
            operator = '/';
            break;
        }
        else
        {
            continue;
        }
    }
    writeData(operator);
}

void calculate()
{
    float n1, n2, r;
    n1 = atof(num1);
    n2 = atof(num2);
    switch(operator)
    {
        case '+':
            r = n1 + n2;
            break;

        case '-':
            r = n1 - n2;
            break;

        case '*':
            r = n1 * n2;
            break;

        case '/':
            if(n2 == 0)
            {
                clearLCD();
                writeStr(0, 0, "Error: Div by 0");
                while(1);
            }
            else
            {
                r = n1 / n2;
            }
            break;

        default:
            clearLCD();
            writeStr(0, 0, "Error: Invalid Op");
            while(1);
    }
    sprintf(result, "%.2f", r);
    clearLCD();
    writeStr(0, 0, "Result:");
    writeStr(7, 0, result);
}

int main()
{
    initLCD();
    while(1)
    {
        readNum1();
        readOp();
        readNum2();
        calculate();
    }
    return 0;
}

注：此代码仅供参考，实际应用中可能需要根据需求进行修改和优化。