51单片机按键控制lcd1602代码

以下是51单片机按键控制LCD1602显示的代码：

#include <regx52.h>
#define LCD1602_DB P0
sbit LCD1602_RS = P2^6;
sbit LCD1602_RW = P2^5;
sbit LCD1602_E = P2^7;

void DelayMs(unsigned int x)
{
    unsigned char j;
    while (x--)
    {
        for (j = 0; j < 110; j++);
    }
}

void LcdWriteCmd(unsigned char cmd)
{
    LCD1602_RS = 0;
    LCD1602_RW = 0;
    LCD1602_E = 0;
    LCD1602_DB = cmd;
    DelayMs(5);
    LCD1602_E = 1;
    DelayMs(5);
    LCD1602_E = 0;
}

void LcdWriteData(unsigned char dat)
{
    LCD1602_RS = 1;
    LCD1602_RW = 0;
    LCD1602_E = 0;
    LCD1602_DB = dat;
    DelayMs(5);
    LCD1602_E = 1;
    DelayMs(5);
    LCD1602_E = 0;
}

void LcdInit()
{
    LcdWriteCmd(0x38); //初始化16*2显示模式，5*7点阵，8位数据接口
    LcdWriteCmd(0x0c); //开启显示，不显示光标
    LcdWriteCmd(0x06); //写入一个字符后地址自动加1
    LcdWriteCmd(0x01); //清屏
}

void Display(unsigned char *s)
{
    while (*s)
    {
        LcdWriteData(*s++);
    }
}

void main()
{
    unsigned char key, flag = 0;
    LcdInit();
    while (1)
    {
        key = P3 & 0x0f;
        if (key != 0x0f)
        {
            DelayMs(5);
            if (key != 0x0f)
            {
                switch (key)
                {
                    case 0x07: //按下key1
                        flag = 1;
                        break;
                    case 0x0b: //按下key2
                        flag = 2;
                        break;
                    case 0x0d: //按下key3
                        flag = 3;
                        break;
                    case 0x0e: //按下key4
                        flag = 4;
                        break;
                }
            }
        }
        if (flag == 1)
        {
            LcdWriteCmd(0x80); //将光标定位到第一行
            Display("Hello, World!");
            flag = 0;
        }
        else if (flag == 2)
        {
            LcdWriteCmd(0x80); //将光标定位到第一行
            Display("Welcome to LCD!");
            flag = 0;
        }
        else if (flag == 3)
        {
            LcdWriteCmd(0xc0); //将光标定位到第二行
            Display("This is 1602 LCD.");
            flag = 0;
        }
        else if (flag == 4)
        {
            LcdWriteCmd(0xc0); //将光标定位到第二行
            Display("Hello, 51 MCU!");
            flag = 0;
        }
    }
}

注：以上代码是一个简单的例子，只是在LCD上显示了几个固定的字符串。如果需要进一步开发，可以根据具体需求对代码进行修改。