1602b_lcd.c

AVR典型实例.rar

//编译器：ICC-AVR v6.31A 日期: 2005-11-24 20:29:57 
//目标芯片 : M16 
//时钟: 8.0000Mhz 
/*------------------------------------------------------------- 
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 <avr\io.h> 

#include "1602LCD.h" 

void LCD_init(void)         //液晶初始化 
{ 
  LCD_DATA_DDR|=LCD_DATA;   //数据口方向为输出 
  LCD_EN_DDR|=LCD_EN;       //设置EN方向为输出 
  LCD_RS_DDR|=LCD_RS;       //设置RS方向为输出 
  LCD_write_command(0x28);  
  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 
{ 
  LCD_EN_PORT|=LCD_EN; 
  delay_nus(1); 
  LCD_EN_PORT&=~LCD_EN; 
} 

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

void LCD_write_data(unsigned char data) //写数据 
{ 
  delay_nus(16); 
  LCD_RS_PORT|=LCD_RS;       //RS=1 
  LCD_DATA_PORT&=0X0f;       //清高四位 
  LCD_DATA_PORT|=data&0xf0;  //写高四位 
  LCD_en_write(); 
  data=data<<4;               //低四位移到高四位 
  LCD_DATA_PORT&=0X0f;        //清高四位 
  LCD_DATA_PORT|=data&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_string(unsigned char X,unsigned char Y,unsigned char *s) //列x=0~15,行y=0,1 
{ 
    LCD_set_xy( X, Y ); //写地址     
    while (*s)  // 写显示字符 
    { 
      LCD_write_data( *s ); 
      s ++; 
    } 
       
} 

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

void delay_1us(void)                 //1us延时函数 
  { 
   asm("nop"); 
  } 

void delay_nus(unsigned int n)       //N us延时函数 
  { 
   unsigned int i=0; 
   for (i=0;i<n;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<n;i++) 
   delay_1ms(); 
  }