lcd_1602.h

altera niosii SOPC helloword 学习

#ifndef __LCD_1602_H_
#define __LCD_1602_H_
#include "system.h"

#define DELAY 1500 
/***********************************************************/
/*DELAY set to delay time for LCD finishing its operation,*/ 
/*When CPU Frequancy is 50MHZ, DELAY set as 2000*/
/*When CPU Frequancy is other value, DELAY set as other value*/
/*For example,when CPU Frequancy is 100MHZ, DELAY set as 4000*/
/*************************************************************/
#define LCD_DATA *(unsigned int *)PIO_LCD_DATA_BASE
#define LCD_DATA_DIR *(unsigned int *)(PIO_LCD_DATA_BASE+4)
#define LCD_CTL *(unsigned int *)PIO_LCD_CTL_BASE
#define LCD_DATA_IN 0
#define LCD_DATA_OUT 0xFF


 void writelcdinstruction(char instru)
 {
  int i;
  for(i=DELAY;i>0;i--) ; 
  LCD_CTL = 0x4;
/*clr RS low */
/*clr R/w for write*/
/*Set enable*/
  LCD_DATA_DIR = LCD_DATA_OUT;
  LCD_DATA = instru;
  for(i=DELAY;i>0;i--) ; 
  LCD_CTL = 0x00;

 }   
   
 void initialcd()
 {
  writelcdinstruction((unsigned int)0x38);  //initialcd
  writelcdinstruction((unsigned int)0x0C);  //initialcd
  writelcdinstruction((unsigned int)0x06); //initialcd
  writelcdinstruction((unsigned int)0x01);  //Clean the LCD
 }
 
 void writelcddata(char lcddata)
 {
  int i;
  for(i=DELAY;i>0;i--) ;  
  LCD_CTL = 0x6; 
/*clr R/w for write*/ 
/*set RS */
/*Set enable*/
  LCD_DATA_DIR = LCD_DATA_OUT;
  LCD_DATA = lcddata;
   for(i=DELAY;i>0;i--) ;  
  LCD_CTL = 0x2;
   for(i=0;i<100;i++) ; 

 }
  
/* void cleanlcd()
 {
  writelcdinstruction((unsigned int)0x01);
  }*/
  
/* void lcddisplay(unsigned int addr,unsigned int data)
  {
   writelcdinstruction(addr);
   writelcddata(data);
  }*/
  
/*  void displayram(unsigned int *valpt)
  {
   int i;
   unsigned int tempval;
   unsigned int val;
   val = *valpt;
   for(i=8;i>0;i--){
    tempval= val & 0xF0000000;
    tempval >>= 28;
     tempval &= 0x0000000F;
    if(tempval>9) tempval+=0x37; //A~F
    else tempval+=0x30;          //0~9
     writelcddata(tempval);
    val <<= 4;
   }
  } */
  
  void displaystring(char addr,char * str)
  {
//   char val;
   writelcdinstruction(addr);
   do {
//       val= *str;
       writelcddata(*str);
       str++;}
   while(*str!='\0');
  }
       
/********************************/
#endif /* __LCD_1602_H_ */