基于51的LCD1602四数据线驱动

/这个程序已经调试过了 
//下面调用实例 
//////////////////////////////////
//LCD1602读写头文件
//四线驱动方式
//////////////////////////////////
#include  
#include "LCD1602.h" 
/*----------- 
管脚定义在液晶头文件中 
-----------*/ 
void main(void){ 
LCD_init(); 
p=LCD_PutStr("Hello Lcd1602!\n",-1); //显示一段文字 
p=LCD_PutNum(1234,2,p); //显示12.34这个数 
while(1); 
}
/*---------------------------------------------------------
液晶LCD1602C 使用4条数据线(D4~D7)
-----------------------------------------------------------*/
/*-------------------------------------------------------------
LCD引脚定义
1---GND 
2---VCC
3---VO
4---RS
5---RW
6---EN
7到14--D0-D7
15--背景灯+
16--背景灯-
-----------------------------------------------------------------*/
#include
#include

#define LCD_DATA P2
sbit LCD1602_RS=P2^2;
sbit LCD1602_EN=P2^3;

int p=0;

/*--------------------------------------------------------------------------------------------------
函数说明
--------------------------------------------------------------------------------------------------*/
void LCD_init(void);
void LCD_en_write(void);
void LCD_write_command(unsigned char command) ;
void LCD_write_data(unsigned char Recdata);
void LCD_set_xy (unsigned char x, unsigned char y);
void LCD_write_string(unsigned char X,unsigned char Y,unsigned char *s);
void LCD_write_char(unsigned char X,unsigned char Y,unsigned char Recdata);
void delay_nus(unsigned int n);
void delay_nms(unsigned int n);

void delay_1us(void)                 //1us延时函数
{
   _nop_();
}

void delay_nus(unsigned int n)       //N us延时函数
{
   unsigned int i=0;
   for (i=0;i   delay_1us();
}

void delay_1ms(void)                 //1ms延时函数
{
   unsigned int i;
   for (i=0;i<1140;i++);
}

void delay_nms(unsigned int n)       //N ms延时函数
{
   unsigned int i=0;
   for (i=0;i   delay_1ms();
}

void LCD_init(void)         //液晶初始化
{

LCD_write_command(0x28);
delay_nus(40); 
LCD_write_command(0x28);
delay_nus(40); 
LCD_write_command(0x28);
delay_nus(40); 

LCD_en_write();
delay_nus(40);
LCD_write_command(0x28); //4位显示
LCD_write_command(0x0c); //显示开
LCD_write_command(0x01); //清屏
delay_nms(2);
}

void LCD_en_write(void) //液晶使能
{
LCD1602_EN=1;
delay_nus(1);
LCD1602_EN=0;
}

void LCD_write_command(unsigned char command) //写指令
{
delay_nus(16);
LCD1602_RS=0;        //RS=0
LCD_DATA&=0X0f;         //清高四位
LCD_DATA|=command&0xf0; //写高四位
LCD_en_write();
command=command<<4;          //低四位移到高四位
LCD_DATA&=0x0f;         //清高四位
LCD_DATA|=command&0xf0; //写低四位
LCD_en_write();

}

void LCD_write_data(unsigned char Recdata) //写数据
{
delay_nus(16);
LCD1602_RS=1;       //RS=1
LCD_DATA&=0X0f;       //清高四位
LCD_DATA|=Recdata&0xf0; //写高四位
LCD_en_write();
Recdata=Recdata<<4;               //低四位移到高四位
LCD_DATA&=0X0f;        //清高四位
LCD_DATA|=Recdata&0xf0;   //写低四位
LCD_en_write();
}

void LCD_set_xy( unsigned char x, unsigned char y ) //写地址函数
{
    unsigned char address;
    if (y == 0) address = 0x80 + x;
    else address = 0xc0 + x;
    LCD_write_command(address);
}

void LCD_write_char(unsigned char X,unsigned char Y,unsigned char Recdata) //列x=0~15,行y=0,1
{
LCD_set_xy(X, Y); //写地址
LCD_write_data(Recdata);
}

int LCD_PutStr(unsigned char *DData,int pos){ 
unsigned char i; 
if(pos==-1){  
   LCD_write_command(0x01); //清屏
   delay_nms(2);
   pos=0; 
   } 
while((*DData)!='\0'){  
switch(*DData){   
     case '\n': //如果是\n，则换行   
     {    
     if(pos<17){     
       for(i=pos;i<16;i++)
         LCD_write_char(i%16, i/16, ' ');
         pos=16;
         }
         else{     
         for(i=pos;i<32;i++) LCD_write_char(i%16, i/16, ' ');
         pos=32;
         }    
     break;   
     }
   
     case '\b': //如果是\b，则退格   
     {
     if(pos>0) pos--;   
     LCD_write_char(pos%16, pos/16, ' ');    
     break;   
     }
   
     default:   
     {    
    
     if((*DData)<0x20){
     *DData=' ';
     }
    
     LCD_write_char(pos%16, pos/16,*DData);
     pos++;    
     break;   
     }  
      }  
      DData++; 
       } 
       return(pos);
       }

//----------------------------以下函数用于输出数字---------------------
int LCD_PutNum(unsigned long num,int XS,int pos){    //从右边数，保留几位小数
unsigned long tmp=0; 
unsigned char numbits=0; 
if(pos==-1){  
LCD_write_command(0x01);
delay_nms(2);  
pos=0; 
} 
if(num==0){  
   LCD_write_char(pos%16, pos/16, '0');
   pos++;
   }
   else{  
   if(num<0){   
   LCD_write_char(pos%16, pos/16, '-');   
   num*=(-1);   
   pos++;  
   }  
   while(num){   
   tmp=tmp*10+(num%10);   
   num=num/10;   
   numbits++;
   }  
   while(tmp){   
   LCD_write_char(pos%16, pos/16, (tmp%10)+48);
   tmp=tmp/10;
   pos++;
   numbits--;
   if(numbits==XS) pos=LCD_PutStr(".",pos); //显示小数点
   }
   while(numbits--){
   LCD_write_char(pos%16, pos/16, '0');
   pos++;
   }
   }
   return(pos);
}