LCD1602 driver based on MEGA16 (four-bit data line)

//Compiler: ICC-AVR v6.31A 
//Target chip: M16 
//Clock: 8.0000MHz 
/*-------------------------------------------------------------

LCD Pin Definition 
1---GND  
2---VCC 
3---VO 
4---RS 
5---RW 
6---EN 
7 to 14--D0-D7 
15--Backlight+ 
16--Backlight- 
---------------------------------------------------------------------------------*/ 
#include  
#include  

/*--------------------------------------------------------------- 
Below is the connection information between AVR and LCD 
PA2 ->RS 
PA3 ->EN 
Ground ->RW 
PA4 ->D4 
PA5 ->D5 
PA6 ->D6 
PA7 ->D7 
To use this driver, just change the following configuration information 
-----------------------------------------------------------------*/ 
#define LCD_EN_PORT PORTA //The following 2 should be set to the same port 
#define LCD_EN_DDR DDRA 
#define LCD_RS_PORT PORTA //The following 2 should be set to the same port 
#define LCD_RS_DDR DDRA 
#define LCD_DATA_PORT PORTA //The following 3 should be set to the same port 
#define LCD_DATA_DDR DDRA //Must use the high 4 bits 
#define LCD_DATA_ PIN    PINA 
#define LCD_RS (1<Function description 
-----------------------------------------------------------------------------*/ 
void LCD_init(void); 
void LCD_en_write( void); 
void LCD_write_command(unsigned char command 
); void LCD_write_data(unsigned char data);  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 delay_nus(unsigned int n); 
void delay_nms(unsigned int n); 
============================================================================= 

#include "LCD.h" 

void LCD_init(void) //LCD initialization 
{ 
  LCD_DATA_DDR|=LCD_DATA; //Data port direction is output 
  LCD_EN_DDR|=LCD_EN; //Set EN direction to output 
  LCD_RS_DDR|=LCD_RS; //Set RS direction to output 
  LCD_write_command(0x28);  
  LCD_en_write(); 
  delay_nus(40); 
  LCD_write_command(0x28); //4-bit display 
  LCD_write_command(0x0c); //Display on 
  LCD_write_command(0x01); //Clear screen 
  delay_nms(2); 
} 

void LCD_en_write(void) //LCD enable 
{ 
  LCD_EN_PORT|=LCD_EN; 
  delay_nus(1); 
  LCD_EN_PORT&=~LCD_EN; 
} 

void LCD_write_command(unsigned char command) //Write command 
{ 
  delay_nus(16); 
  LCD_RS_PORT&=~LCD_RS; //RS=0 
  LCD_DATA_PORT&=0X0f; //Clear four bits 
  LCD_DATA_PORT|=command&0xf0; //Write high four bits 
  LCD_en_write(); 
  command=command<<4; //Move low four bits to high four bits 
  LCD_DATA_PORT&=0x0f; //Clear high four bits 
  LCD_DATA_PORT|=command&0xf0; //Write low four bits 
  LCD_en_write(); 
   
} 

void LCD_write_data(unsigned char data) //Write data 
{ 
  delay_nus(16); 
  LCD_RS_PORT|=LCD_RS; //RS=1 
  LCD_DATA_PORT&=0X0f; //Clear high four bits 
  LCD_DATA_PORT|=data&0xf0; //Write high four bits 
  LCD_en_write(); 
  data=data<<4; //Move low four bits to high four bits 
  LCD_DATA_PORT&=0X0f; //Clear high four bits 
  LCD_DATA_PORT|=data&0xf0; //Write low four bits 
  LCD_en_write(); 
} 


void LCD_set_xy( unsigned char x, unsigned char y ) //Write address function 
{ 
    unsigned char address; 
    if (y == 0) address = 0x80 + x; 
    else address = 0xc0 + x; 
    LCD_write_command( address); 
} 
   
void LCD_write_string(unsigned char Y )      ; //Write address      while (*s) //Write     display      characters 
{        LCD_write_data( *s );        s ++;      }  }  void LCD_write_char(unsigned char X, unsigned char Y, unsigned char data   )  //Column x=0~15, row y=0,1  {    LCD_set_xy  (  =======================================================================  void delay_1us(void) //1us delay function    {     asm("nop");    }  void delay_nus(unsigned int n) //N us delay function    {     unsigned int i=0;     for (i=0;i





       






   













   





   



























   LCD_write_char(6,0,'8');    
   } 
  
}

0 0| 0 1 0 0 // 0x04 | 0 0 0| 0 0 
1  0  0       //       0x04       |  0       0  0       |  0       1  1  1  0 //       0x00  unsigned 
char  data[8]={0x04,0x0e,0x15,0x04,0x04,0x04,0x04,0x00};//↑  unsigned char data1[8]={0x04,0x04,0x04,0x04,0x15,0x0e,0x04,0x00};//↓  void my_signs(unsigned char ascii,unsigned char *z)//0x00  {    unsigned char address=0,i,temp=0; //ascii is the ascii code value corresponding to the pattern to be defined (0x00 to    temp=(ascii&0x07)<<3; //any value between 0x007)     for(i=0;i<8;i++)     {          address = 0x40 +temp+ i;        LCD_write_command( address );        delay_nus(1);        LCD_write_data ( *(z++));        delay_nus(1);     }  }  //Create pattern  void LCD_init(void) //LCD initialization  {   LCD_DATA_DDR|=LCD_DATA; //Data is output   LCD_EN_DDR|=LCD_EN; //Set RS.EN direction   LCD_RS_DDR|=LCD_RS;   LCD_write_command(0x28); //4-bit display    LCD_en_write();    delay_nms(15);   LCD_write_command(0x28); //4-bit display   LCD_write_command(0x0c); //Display on    my_signs(0x00,data);//↑ //Create pattern   my_signs(0x01,data1);//↓   LCD_write_command(0x01); //Clear screen  }  Display custom pattern  LCD_write_char(9,0,0x00);//↑  LCD_write_char(9,0,0x01);//↓

Special Tip: If the compilation fails, please delete the header file