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LCD 1602A

PIN	Symbol	Description
1	VSS	电源地
2	VDD	电源正极
3	VL	液晶显示偏压信号
4	RS	数据/命令选择端(H/L)
5	R/W	读/写选择端(H/L)
6	E	使能信号
7	D0	Data I/O
8	D1	Data I/O
9	D2	Data I/O
10	D3	Data I/O
11	D4	Data I/O
12	D5	Data I/O
13	D6	Data I/O
14	D7	Data I/O
15	BLA	背光源正极
16	BLK	背光源负极

/************************
AT89C51
LCD 1602A
*************************/

#include <reg52.h>
#include <intrins.h>

sbit RS = P1 ^ 0;
sbit RW = P1 ^ 1;
sbit EN = P2 ^ 5;

#define RS_CLR RS = 0
#define RS_SET RS = 1

#define RW_CLR RW = 0
#define RW_SET RW = 1

#define EN_CLR EN = 0
#define EN_SET EN = 1

#define DataPort P0

/***************************
 * OSC 12 MHz
 * T = tx2 + 5us
 ****************************/
void DelayUs2x(unsigned char t)
{
    while (--t)
        ;
}

void DelayMs(unsigned char t)
{
    while (--t)
    {
        // delay about 1ms
        DelayUs2x(245);
        DelayUs2x(245);
    }
}

bit LCD_Check_Busy(void)
{
    RS_CLR;
    RW_SET;
    EN_CLR;
    _nop_();
    EN_SET;
    return (bit)(DataPort & 0x80); // 0x80; 0x00;
}

void LCD_Write_Com(unsigned char com)
{
    while (LCD_Check_Busy())
        ;
    RS_CLR;
    RW_CLR;
    EN_SET;
    DataPort = com;
    _nop_();
    EN_CLR;
}

void LCD_Write_Data(unsigned char Data)
{
    while (LCD_Check_Busy())
        ;
    RS_SET;
    RW_CLR;
    EN_SET;
    DataPort = Data;
    _nop_();
    EN_CLR;
}

void LCD_Clear(void)
{
    LCD_Write_Com(0x01);
    DelayMs(5);
}

void LCD_Write_String(unsigned char x, unsigned char y, unsigned char *s)
{
    if (y == 0)
    {
        LCD_Write_Com(0x80 + x); // Line 1
    }
    else
    {
        LCD_Write_Com(0xC0 + x); // Line 2
    }
    while (*s)
    {
        LCD_Write_Data(*s);
        s++;
    }
}

void LCD_Write_Char(unsigned char x, unsigned char y, unsigned char Data)
{
    if (y == 0)
    {
        LCD_Write_Com(0x80 + x);
    }
    else
    {
        LCD_Write_Com(0xC0 + x);
    }
    LCD_Write_Data(Data);
}

void LCD_Init(void)
{
    LCD_Write_Com(0x38); // display mode settings
    DelayMs(5);
    LCD_Write_Com(0x38);
    DelayMs(5);
    LCD_Write_Com(0x38);
    DelayMs(5);
    LCD_Write_Com(0x38);
    LCD_Write_Com(0x08); // display off
    LCD_Write_Com(0x01); // clear screen
    LCD_Write_Com(0x06); // cursor display settings
    DelayMs(5);
    LCD_Write_Com(0x0C); // open display & cursor set
}

void main(void)
{
    LCD_Init();
    LCD_Clear();
    while (1)
    {
        LCD_Write_Char(7, 0, '0');
        LCD_Write_Char(8, 0, 'k');
        LCD_Write_String(1, 1, "hello world");
        while (1)
            ;
    }
}

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LCD 1602A

PIN