7920.c

7920两行中文液晶显示屏的源程序及电路图 (ICC)

//本程序是7920的LM3037的液晶驱动程序
//汉字2x9
//ATMEGA16, 内部晶振8M  
//使用串行传输 
//本程序测试通过

//绿叶子整理 -- 2005.08.30

#include <iom16v.h>
#include <macros.h>

#define LCD_DATA_PORT  PORTA
#define LCD_DATA_DDR   DDRA
#define LCD_DATA_PIN   PINA
#define LCD_DATA       0x0ff   //portA   out

#define LCD_CONTROL_PORT    PORTB
#define LCD_CONTROL_DDR     DDRB

#define	RS	 0      //RS(CS) 可直接接VCC -- 替代
#define	RW	 1      //RW(SID) 
#define	E	 2      //E(sclk)
#define	PSB	 3      //可以直接接地  -- 替代
#define	_RES	 4  //可以去掉

/*--------------------------------------------------------------------------------------------------
Public function prototypes
--------------------------------------------------------------------------------------------------*/
void delay_1us(void);
void delay_1ms(void);
void delay_nus          (unsigned int n);
void delay_nms          (unsigned int n);

#define	SETBIT(x,y) (x|=(1<<y))      //set bit y in byte x
#define	CLRBIT(x,y) (x&=(~(1<<y)))   //clear bit y in byte x
#define	CHKBIT(x,y) (x&(1<<y))       //check bit y in byte x

#define uchar unsigned char // 0~255
#define uint unsigned int   // 0~65535

void  CheckState();
void initLCDM(void);
void Send(unsigned char senddata);
void SdCmd(unsigned char scmd);
void SdData(unsigned char DData); 
void WriteTextScreen(unsigned char *TxtData);
void WriteTextScreen2(unsigned char *pstr);
void WriteGraphicScreen(unsigned char *GDData);

void DispSetCursor(unsigned char LineNum, unsigned char ColumnNum);

unsigned char  TextLogo[]={"液晶显示模块(LCDM)"};

void initLCDM(void)
{
	delay_nms(100);

 	//端口初始化
	//LCD_DATA_DDR=0xFF;
	LCD_CONTROL_DDR=0xFF; 

	CLRBIT(LCD_CONTROL_PORT,E);
	CLRBIT(LCD_CONTROL_PORT,RW);
	CLRBIT(LCD_CONTROL_PORT,RS);
	CLRBIT(LCD_CONTROL_PORT,PSB);
	
	//LCD_DATA_PORT|=0x0;	
	//delay_nms(1500);
		
	LCD_DATA_PORT|=0xFF;
		
	//SETBIT(LCD_CONTROL_PORT,_RES);
	CLRBIT(LCD_CONTROL_PORT,_RES);
	delay_nms(1);
	SETBIT(LCD_CONTROL_PORT,_RES);

	SdCmd(0x20);    // 8bit I/F, basic command, graphic off
	SdCmd(0x20);    // 8bit I/F, basic command, graphic off
	SdCmd(0x0C);    // display on
	SdCmd(0x06);    // cursor right shift
	SdCmd(0x01);    // cursor right shift

}

/*-----------------------------------------------------
  状态检查函数,判断是否处于忙状态
-------------------------------------------------------*/
void  CheckState()
{
 	unsigned char dat;
 	CLRBIT(LCD_CONTROL_PORT,RS);  //RS=0
 	SETBIT(LCD_CONTROL_PORT,RW);  //RW=1
 	LCD_DATA_DDR=0x00;			// portA as input
 	do
 	{
 	   	SETBIT(LCD_CONTROL_PORT,E);
		NOP();
		CLRBIT(LCD_CONTROL_PORT,E);
    }
 	while (LCD_DATA_PIN&0x80);
}

void Send(unsigned char senddata)
{
	unsigned char i;

	for(i=0;i<8;i++)
	{
		if((senddata)&0x80)
		{
			//D_OUT=1	   ;	
			SETBIT(LCD_CONTROL_PORT,RW);	
		}
		else
		{
			//D_OUT=0;	
			CLRBIT(LCD_CONTROL_PORT,RW);		
		}
		
		//SCK=1;
		SETBIT(LCD_CONTROL_PORT,E);	
		NOP();
		//SCK=0;
		CLRBIT(LCD_CONTROL_PORT,E);	
		
		senddata<<=1;
	}
}

void SdCmd(unsigned char scmd)   //send command
{
	//ST7920CS=1;
	SETBIT(LCD_CONTROL_PORT,RS);
	Send(0xf8);
	Send(scmd&0xf0);
	Send(scmd<<4);	
	
	//ST7920CS=0;
	SETBIT(LCD_CONTROL_PORT,RS);
	delay_nus(20);
	
}

void SdData(unsigned char DData) 
{
	//ST7920CS=1;
	SETBIT(LCD_CONTROL_PORT,RS);
	Send(0xfa);
	Send(DData&0xf0);
	Send(DData<<4);	
	
	//ST7920CS=0;
	SETBIT(LCD_CONTROL_PORT,RS);
	delay_nus(20);
	
}

void main(void)
{
 
	CLI();                 // disable interrupts

   	initLCDM();
	
	while(1)
	{
	SdCmd(0x20);          // 8bit I/F, basic command, graphic off
	SdCmd(0x01);          // clr text screen
	delay_nms(100);
	
    WriteTextScreen2(TextLogo);
   	delay_nms(1500);

    WriteTextScreen2("世界你好12345678901234567890");
   	delay_nms(1500);

	
 	}
	

}

void DispSetCursor(unsigned char LineNum, unsigned char ColumnNum)
{

    unsigned char i=0x00;
    switch(LineNum&0x0f)   //确定行号
    {
	case 0x00:
		i=0x80;
		break;
	case 0x01: 
		i=0x90; 
		break;
	case 0x02: 
		i=0x88;
		break;
	case 0x03:
		i=0x98;
		break;
	default : 
		break;
    }
    i = (ColumnNum&0x0f)|i; //确定列号
   SdCmd(i);
	
}

void WriteTextScreen2(unsigned char *pstr)
{
unsigned char i;
unsigned char j;

   	SdCmd(0x34);        // 8bit I/F, basic command
   	SdCmd(0x30);        // 8bit I/F, basic command, graphic off

	 for(i=0;i<36;i++)       //清空屏幕
	 {
		 if (i%18==0)         //判断是否换行
		 {
			 DispSetCursor(i/18,0);   //如换行, 则光标移动到行首
		 }

		 SdData(' '); //
	 }
		
     j=0;
     //while (*pstr)
     while (*pstr && j<36)
     {
		 if (j%18==0)         //判断是否换行
		 {
			 DispSetCursor(j/18,0);   //如换行, 则光标移动到行首
		 }
		 
		 //避免最后一格写半个汉字, 把汉字写到下一行
		 if (((j+1)%18==0) && *pstr>127 && *(pstr-1)<128) 
		 {
		 	SdData(' '); //
			j++;
		 }
		else
		{	
		 	SdData(*pstr++);
		 	j++;
		}
		
        //SdData(*pstr++);
        //j++;		
     }

 }

/*-----------------------------------------------------------------------
延时函数
系统时钟：8M
-----------------------------------------------------------------------*/
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();
  }