用c语言编写一个驱动51单片机设计的简易计算器的

首先，需要连接一个4x4矩阵键盘到51单片机上，然后按照下面的步骤进行编写：

1. 定义键盘端口和显示屏端口。

sbit ROW1 = P2^0;
sbit ROW2 = P2^1;
sbit ROW3 = P2^2;
sbit ROW4 = P2^3;

sbit COL1 = P2^4;
sbit COL2 = P2^5;
sbit COL3 = P2^6;
sbit COL4 = P2^7;

sbit LSA = P0^2;
sbit LSB = P0^3;
sbit LSC = P0^4;

2. 定义函数用于扫描键盘输入。

unsigned char KeyScan()
{
    unsigned char row = 0, col = 0, key = 0xFF;
    ROW1 = 0; ROW2 = 1; ROW3 = 1; ROW4 = 1;
    if (COL1 == 0) { col = 1; }
    if (COL2 == 0) { col = 2; }
    if (COL3 == 0) { col = 3; }
    if (COL4 == 0) { col = 4; }
    ROW1 = 1; ROW2 = 0; ROW3 = 1; ROW4 = 1;
    if (COL1 == 0) { col = 1; }
    if (COL2 == 0) { col = 2; }
    if (COL3 == 0) { col = 3; }
    if (COL4 == 0) { col = 4; }
    ROW1 = 1; ROW2 = 1; ROW3 = 0; ROW4 = 1;
    if (COL1 == 0) { col = 1; }
    if (COL2 == 0) { col = 2; }
    if (COL3 == 0) { col = 3; }
    if (COL4 == 0) { col = 4; }
    ROW1 = 1; ROW2 = 1; ROW3 = 1; ROW4 = 0;
    if (COL1 == 0) { col = 1; }
    if (COL2 == 0) { col = 2; }
    if (COL3 == 0) { col = 3; }
    if (COL4 == 0) { col = 4; }
    if (col != 0)
    {
        switch (row)
        {
            case 0: key = col; break;
            case 1: key = col + 4; break;
            case 2: key = col + 8; break;
            case 3: key = col + 12; break;
        }
    }
    return key;
}

3. 定义函数用于显示结果。

void Display(unsigned char num)
{
    switch (num)
    {
        case 0: LSA = 0; LSB = 0; LSC = 0; break;
        case 1: LSA = 1; LSB = 0; LSC = 0; break;
        case 2: LSA = 0; LSB = 1; LSC = 0; break;
        case 3: LSA = 1; LSB = 1; LSC = 0; break;
        case 4: LSA = 0; LSB = 0; LSC = 1; break;
        case 5: LSA = 1; LSB = 0; LSC = 1; break;
        case 6: LSA = 0; LSB = 1; LSC = 1; break;
        case 7: LSA = 1; LSB = 1; LSC = 1; break;
    }
}

4. 在主函数中，使用一个循环来读取键盘输入并执行相应的操作。

void main()
{
    unsigned char key = 0xFF, num1 = 0, num2 = 0, result = 0;
    while (1)
    {
        key = KeyScan();
        if (key != 0xFF)
        {
            if (key >= 1 && key <= 9)
            {
                if (num1 == 0)
                {
                    num1 = key;
                    Display(num1);
                }
                else if (num2 == 0)
                {
                    num2 = key;
                    Display(num2);
                }
            }
            else if (key == 10)
            {
                result = num1 + num2;
                Display(result);
            }
            else if (key == 11)
            {
                result = num1 - num2;
                Display(result);
            }
            else if (key == 12)
            {
                result = num1 * num2;
                Display(result);
            }
            else if (key == 13)
            {
                result = num1 / num2;
                Display(result);
            }
            else if (key == 14)
            {
                num1 = 0;
                num2 = 0;
                result = 0;
                LSA = 1; LSB = 1; LSC = 1;
            }
        }
    }
}

在这个简易计算器中，1~9为数字键，10为加法键，11为减法键，12为乘法键，13为除法键，14为清零键。当用户按下数字键时，程序会将该数字存储在num1或num2中，并在显示屏上显示出来。当用户按下运算符键时，程序会执行相应的运算并将结果显示在屏幕上。当用户按下清零键时，程序会将所有变量清零并将显示屏清空。