LCD display module 1602 driver source code

LCD display module 1602 driver source code

//lcd1602 drive program for 51 mcu
//designed by Wangchao
//2006-6-14

＃i nclude "reg52.h"
/********************************************************************/
//lcd part
#define  LINE1     0
#define  LINE2     1
#define  LINE1_HEAD    0x80
#define  LINE2_HEAD    0xC0
#define  LCD_DELAY_TIME   40
#define  DATA_MODE    0x38
#define  OPEN_SCREEN    0x0C
#define  DISPLAY_ADDRESS   0x80
#define  CLEARSCREEN    LCD_en_command(0x01)
//common part
#define  HIGH   1
#define  LOW    0
#define  TRUE    1
#define  ZERO    0

/*******************************************************************/
//change this part at different board
#define  LCDIO     P2
sbit LCD1602_RS=P0^7;   //data command select  1 data  0 command  pin 4
sbit LCD1602_RW=P0^6;   //read write select   1 read   0 write     pin 5
sbit LCD1602_EN=P0^5;   //LCD enable signal             pin 6

/********************************************************************/
void LCD_delay(void);//lcd delay
void LCD_en_command(unsigned char command);//write command
void LCD_en_dat(unsigned char temp);//write data
void LCD_set_xy( unsigned char x, unsigned char y );//set display address
void LCD_write_char( unsigned x,unsigned char y,unsigned char dat);//write lcd a character
void LCD_write_string(unsigned char X,unsigned char Y,unsigned char *s);//write lcd string
void LCD_init(void);//lcd initize

/********************************************************************/
void delay_nms(unsigned int n);//delay

/********************************************************************/
void main(void)
{
LCD_init();
while(TRUE )
{
CLEARSCREEN;

delay_nms(2);
LCD_write_string(0,LINE1,"Wellcome to DLUT");
LCD_write_string(0,LINE2,"www.dlut.edu.cn!");

delay_nms(500);

CLEARSCREEN;

delay_nms(2);
LCD_write_string(0,LINE1,"   lcd test     ");
LCD_write_string(0,LINE2,"   successful!  ");

delay_nms(500);

CLEARSCREEN;

delay_nms(2);
LCD_write_string(0,LINE1," I'm WangChao.  ");
LCD_write_string(0,LINE2,"   Thank You!  ");

delay_nms(500);
}
}
/********************************************************************/
/******************** LCD PART *************************************/
void LCD_delay(void)
{
unsigned char i;
for(i=LCD_DELAY_TIME;i>ZERO;i--)  //be sure lcd reset
;
}
/********************************************************************/
void LCD_en_command(unsigned char command)
{
LCDIO=command;
LCD1602_RS=LOW;
LCD1602_RW=LOW;
LCD1602_EN=LOW;
LCD_delay();
LCD1602_EN=HIGH;
}
/********************************************************************/
void LCD_en_dat(unsigned char dat)
{
LCDIO=dat;
LCD1602_RS=HIGH;
LCD1602_RW=LOW;
LCD1602_EN=LOW;
LCD_delay();
LCD1602_EN=HIGH;
}
/********************************************************************/
void LCD_set_xy( unsigned char x, unsigned char y )
{
unsigned char address;
if (y == LINE1)
address = LINE1_HEAD + x;
else
address = LINE2_HEAD + x;
LCD_en_command(address);
}
/********************************************************************/
void LCD_write_char( unsigned x,unsigned char y,unsigned char dat)
{
LCD_set_xy( x, y );
LCD_en_dat(dat);
}
/********************************************************************/
void LCD_write_string(unsigned char X,unsigned char Y,unsigned char *s)
{
LCD_set_xy( X, Y ); //set address
while (*s)  // write character
{
LCDIO=*s;
LCD_en_dat(*s);
s ++;
}
}
/********************************************************************/
void LCD_init(void)
{
CLEARSCREEN;//clear screen
LCD_en_command(DATA_MODE);//set 8 bit data transmission mode
LCD_en_command(OPEN_SCREEN);//open display (enable lcd display)
LCD_en_command(DISPLAY_ADDRESS);//set lcd first display address
CLEARSCREEN;//clear screen
}
/********************************************************************/
/*********************** OTHER PART *********************************/
void delay_nms(unsigned int n)
{
unsigned int i=0,j=0;
for (i=n;i>0;i--)
for (j=0;j<1140;j++);
}
/********************************************************************/