51单片机lcd1602利用e1的4*4矩阵键盘显示数字

首先，你需要连接51单片机和LCD1602显示屏。然后，连接4*4矩阵键盘到51单片机的E1引脚。

接下来，你需要编写51单片机的程序，使其能够读取4*4矩阵键盘的输入，并将数字显示在LCD1602屏幕上。以下是一个简单的示例程序：

#include <reg51.h>

#define LCD_DB P0
sbit LCD_RS = P2^6;
sbit LCD_EN = P2^7;

unsigned char KeyTable[4][4] = {
    {'1', '2', '3', 'A'},
    {'4', '5', '6', 'B'},
    {'7', '8', '9', 'C'},
    {'*', '0', '#', 'D'}
};

void Delay10ms() {
    unsigned char i, j;

    i = 25;
    j = 214;
    do {
        while (--j);
    } while (--i);
}

void LCD_WriteCmd(unsigned char cmd) {
    LCD_RS = 0;
    LCD_DB = cmd;
    LCD_EN = 1;
    Delay10ms();
    LCD_EN = 0;
}

void LCD_WriteData(unsigned char dat) {
    LCD_RS = 1;
    LCD_DB = dat;
    LCD_EN = 1;
    Delay10ms();
    LCD_EN = 0;
}

void LCD_Init() {
    LCD_WriteCmd(0x38);
    LCD_WriteCmd(0x0c);
    LCD_WriteCmd(0x06);
    LCD_WriteCmd(0x01);
}

unsigned char KeyScan() {
    unsigned char i, j, key;

    P1 = 0xf0;
    if (P1 != 0xf0) {
        Delay10ms();
        if (P1 != 0xf0) {
            key = P1;
            P1 = 0x0f;
            switch (key) {
                case 0x70: i = 0; break;
                case 0xb0: i = 1; break;
                case 0xd0: i = 2; break;
                case 0xe0: i = 3; break;
            }
            switch (P1) {
                case 0x07: j = 0; break;
                case 0x0b: j = 1; break;
                case 0x0d: j = 2; break;
                case 0x0e: j = 3; break;
            }
            return KeyTable[i][j];
        }
    }
    return 0xff;
}

void main() {
    unsigned char key;

    LCD_Init();

    while (1) {
        key = KeyScan();
        if (key != 0xff) {
            LCD_WriteCmd(0x01);
            LCD_WriteData(key);
        }
    }
}

这个程序会将4*4矩阵键盘的输入映射到KeyTable数组中，然后将相应的数字显示在LCD1602屏幕上。你可以根据自己的需要修改程序来实现更复杂的功能。