lcd.c :

*/
/**
* \addtogroup LCD
* @{
*/
#include <absacc.h>
#include "LCD.h"
#include <intrins.h>

#define LCD_IR 0
#define LCD_DR 1

//unsigned char puchStr[10] = "Hallo";
//LCD_WriteString(char*puchStr);
//index = 0;
//while(puchStr[index]);
//LCD_WriteChar(puchStr[index]);
//index++;

/**
* Initialisiere Display
* @param keine
* @return nichts
*/
void LCD_Init()
{
    LCD_WriteIR(LCD_FUNCTION_SET | LCD_FUNCTION_SET_8BIT); //das | =bitweise verknüpfen
    LCD_Wait100us(50); //wait 5ms
    LCD_WriteIR(LCD_FUNCTION_SET | LCD_FUNCTION_SET_8BIT);

    LCD_Wait100us(2); //wait 100us
    LCD_WriteIR(LCD_FUNCTION_SET | LCD_FUNCTION_SET_8BIT);
    LCD_Wait100us(2); //wait 100us


    while(LCD_IsBusy())
    {

    }

    LCD_WriteIR(LCD_FUNCTION_SET | LCD_FUNCTION_SET_8BIT | LCD_FUNCTION_SET_2LINE | LCD_FUNCTION_SET_F5x8 );

    LCD_WriteIR(LCD_DC_DISPL | LCD_DC_DISPL_DOFF | LCD_DC_DISPL_B);

    LCD_WriteIR(LCD_CLEAR_DISPL);

    LCD_WriteIR(LCD_ENTRY_MODE_SET | LCD_ENTRY_MODE_SET_I | LCD_ENTRY_MODE_SET_S_OFF);

    LCD_WriteIR(LCD_DC_DISPL | LCD_DC_DISPL_DON | LCD_DC_DISPL_CON  | LCD_DC_DISPL_B);

}
/**
* Schreiben ins Instructor Register
* @param uchInstr
* @return nichts
*/
void LCD_WriteIR(unsigned char uchInstr)
{
    LCD_Write(uchInstr, LCD_IR);
}
/**
* Schreiben ins Data Register
* @param uchInstr
* @return nichts
*/
void LCD_WriteDR(unsigned char uchInstr)
{
    LCD_Write(uchInstr, LCD_DR);
}
/**
* Ruft LCD_WriteDR oder LCD_WriteIR auf
* @param uchVal
* @param bReg
* @param bCheckB
* @return nichts
*/
void LCD_Write(unsigned char uchVal, bit bReg)
{
    #ifdef LCD_MEMMAPPED


     if(bReg == LCD_IR)
         {
             //write IR
             XBYTE[LCD_ADDR_IR] = uchVal;
         }
         else
         {
             //write DR
             XBYTE[LCD_ADDR_DR] = uchVal;
         }
         /*
         while(LCD IsBusy)
         LCD_WriteIRNoBF(val){
         LCD_Write(val,LCD_IR,0)
         }LCD_WriteIR(val){
         LCD_Write(val,LCD_IR,1)
         }
         LCD_WriteDR(val){
         LCD_Write(val,DR,1)
         }
         */
    #elif defined (LCD_PORTMAPPDE)
    //Code für PORT
    //SETB
    #else
         #error "Fehler beim Definieren von Port- oder Memmapped"
    #endif
}
/**
* Funktion zum Warten des Vilefachen von 100us(NOP = 0.5us)
* @param uchTimes
* @return nichts
*/
void LCD_Wait100us(unsigned char uchTimes)
{
  unsigned char uchTemp;
    while(uchTimes != 0)
    {
      for(uchTemp = 0; uchTemp <= 50; uchTemp++)
      {
      _nop_();
      _nop_();
      _nop_();
      }
      uchTimes--;
  }
}
/**
* Erkennt ob das BusyFlag gesetzt ist
* @return
*/
bit LCD_IsBusy()
{
    return(LCD_Read(LCD_ADDR_IR) & LCD_BF_MASK);
}
/**
* Ruft oder LCD_ReadIR auf
* @param bReg
* @return
*/
unsigned char LCD_Read(bit bReg)
{
    if(bReg == LCD_IR)
    {
             //read IR
      return(XBYTE[LCD_ADDR_IR]);
    }
    else
    {
             //read DR
      return(XBYTE[LCD_ADDR_DR]);
    }
}
/**
* Liest vom Data Register
* @param keine
* @return  gelesenes
*/
unsigned char LCD_ReadDR()
{
    return(LCD_Read(LCD_DR));
}
/**
* Liest vom Instruction Register
* @param keine
* @return gelesenes
*/
unsigned char LCD_ReadIR()
{
    return(LCD_Read(LCD_IR));
}
/**
* Setzt den Coursor auf eine bestimmte Position
* @param uchZeile
* @param uchSpalte
* @return
*/
unsigned char Cursor_GoToXY(unsigned char uchZeile, unsigned char uchSpalte)
{

}

char putchar(char chc)
{
    if(chc = '\n')
    {

    }

    if(chc == '\t')
    {

    }

    if(chc == '\b')
    {

    }

    LCD_WriteDR(chc);
    return (chc);
}
//@}

lcd.h:

#ifndef _LCD_H
#define _LCD_H

//entweder MEM- oder PORT- MAPPED einstellen
#define LCD_MEMMAPPED
//#define LCD_PORTMAPPED

//MEMMAPPED settings
#define LCD_ADDR_IR 0x0000
#define LCD_ADDR_DR 0x4000

//PORTMAPPED settings

#define LCD_CLEAR_DISPL 0x01 //oder (1<<5)=einser um 5 stellen nach links versch.
#define LCD_RETURN_HOME 0x02
#define LCD_ENTRY_MODE_SET 0x04
#define LCD_ENTRY_MODE_SET_I 0x02
#define LCD_ENTRY_MODE_SET_D 0x00
#define LCD_ENTRY_MODE_SET_S_ON 0x01
#define LCD_ENTRY_MODE_SET_S_OFF 0x00
#define LCD_DC_DISPL 0x08
#define LCD_DC_DISPL_DON 0x04
#define LCD_DC_DISPL_DOFF 0x00
#define LCD_DC_DISPL_CON 0x02
#define LCD_DC_DISPL_COFF 0x00
#define LCD_DC_DISPL_B 0x01
#define LCD_CDS 0x10
#define LCD_CDS_DISPL_SHIFT 0x08
#define LCD_CDS_CURSOR_MOVE 0x00
#define LCD_CDS_LINKS 0x00
#define LCD_CDS_RECHTS 0x04
#define LCD_FUNCTION_SET 0x20
#define LCD_FUNCTION_SET_4BIT 0x00
#define LCD_FUNCTION_SET_8BIT 0x10
#define LCD_FUNCTION_SET_1LINE 0x00
#define LCD_FUNCTION_SET_2LINE 0x08
#define LCD_FUNCTION_SET_F5x10 0x04
#define LCD_FUNCTION_SET_F5x8 0x00

#define LCD_BF_MASK 0x80
#define LCD_LINE_LENGHT 20
#define LCD_ADDR_LINE1 0
#define LCD_ADDR_LINE2 0x40
#define LCD_ADDR_LINE3 (LCD_ADDR_LINE1+LCD_LINE_LENGHT)

//(mit const davor in den code speicher)char la[] = {LCD_ADDR_LINE1, LCD_ADDR_LINE2, LCD_ADDR_LINE3}

//Prototypes
void LCD_Init();

void LCD_WriteIR(unsigned char uchInstr);

void LCD_WriteDR(unsigned char uchInstr);

void LCD_Write(unsigned char uchVal, bit bReg);

void LCD_Wait100us(unsigned char uchTimes);

bit LCD_IsBusy();

unsigned char LCD_Read(bit bReg);

unsigned char LCD_ReadDR();

unsigned char LCD_ReadIR();

unsigned char Cursor_GotToXY(unsigned char uchZeile, unsigned char uchSpalte);

#endif /* _LCD_H */


main.c:

#include <reg8253.h>
#include "LCD.h"
#include <stdio.h>

void main (void)
{
    LCD_Init();
  printf("hallo\t");
}