lcd.c

/*------------------------------------------------------------------------------

 Copyright:      Radig Ulrich  mailto: mail@ulrichradig.de

 Author:         Radig Ulrich

 Remarks:        

 known Problems: none

 Version:        22.11.2007

 Description:    Programm zur Ansteuerung eines Standart LCD

         (HD44870),(SED1278F) und kompatible

------------------------------------------------------------------------------*/

#include <stdlib.h>

#include <stdarg.h>

#include <ctype.h>

#include <string.h>

#include <avr/io.h>

#include <avr/pgmspace.h>

#include "lcd.h"

#include <avr/delay.h>

//const char LINE_ADDRESS[] ={0x80,0xC0,0x90,0xD0}; //2 x 16;4 x 16 uvm.

const char LINE_ADDRESS[] ={0x80,0xC0,0x94,0xD4}; //4 mal 20

volatile unsigned char back_light = 0;

//------------------------------------------------------------------------------

void enable(void)

{

  PORT_LCD_DATA_ENABLE |= (1<<LCD_DATA_ENABLE);

  _delay_ms(50);

  PORT_LCD_DATA_ENABLE &= ~(1<<LCD_DATA_ENABLE);

  _delay_ms(50);

}

void Clock (void)

{

  PORT_LCD_CLOCK |= (1<<LCD_CLOCK); //Clock PIN (High)

  _delay_ms(20);

  PORT_LCD_CLOCK &= ~(1<<LCD_CLOCK); //Clock PIN (Low)

  _delay_ms(20);

}

void lcd_char(char ps, char cd)

{

  switch(ps)

  {

    case 'ä' : ps = 0xE1; break;

    case 'ö' : ps = 0xEF; break;

    case 'ü' : ps = 0xF5; break;

    case 'ß' : ps = 0xE2; break;

    case '°' : ps = 0xDF; break;

    case 'µ' : ps = 0xE4; break;

    case 'Ä' : ps = 0x00; break;  // Point to CG-RAM

    case 'Ö' : ps = 0x01; break; // self defined characters

    case 'Ü' : ps = 0x02; break;

  }

  lcd_write(ps,1);

}

void lcd_init (void)

{  

  //Set Port Direction Register  

  DDRB =0xff;

  DDR_LCD_DATA_ENABLE  |= (1<<LCD_DATA_ENABLE);

  DDR_LCD_CLOCK |= (1<<LCD_CLOCK);

  DDR_LCD_DATA |= (1<<LCD_DATA);

  PORT_LCD_DATA_ENABLE &= ~(1<<LCD_DATA_ENABLE);

  shift_data_out(0x02<<3);

  _delay_us(10);

  shift_data_out(0x02<<3);

  _delay_us(10);

  shift_data_out(0x08<<3);

  _delay_us(10);

  shift_data_out(0x00<<3);

  _delay_us(10);

  shift_data_out(0x0F<<3);

  _delay_us(10);

  shift_data_out(0x00<<3);

  _delay_us(10);

  shift_data_out(0x01<<3);

  _delay_us(10);

  shift_data_out(0x00<<3);

  _delay_us(10);

  shift_data_out(0x0C<<3);

  _delay_us(10);

};

//------------------------------------------------------------------------------

void lcd_write (char data,char cd)

  {  

  unsigned char h_nibble = 0;

  unsigned char l_nibble = 0;

  _delay_us(10);

  //Soll ins Steuer oder Datenregister geschrieben werden?

  if(cd)

  {

    h_nibble &=~ (1<<LCD_RS_PIN);

  }

  else

  {

    l_nibble |= (1<<LCD_RS_PIN);

  }

  if(back_light)

  {

    h_nibble |= (1<<LCD_LIGHT_PIN);

    l_nibble |= (1<<LCD_LIGHT_PIN);

  }

  h_nibble |= (data&0xF0)>>1; //Write Nibbel MSB

  _delay_ms(10);

  l_nibble |= (data&0x0F)<<3; //Write Nibbel LSB

  _delay_ms(10);

  //Schreiben der 1. 4Bit an das LCD Display

  shift_data_out(h_nibble);

  //Schreiben der 2. 4Bit an das LCD Display  

  shift_data_out(l_nibble);

};

//------------------------------------------------------------------------------

void shift_data_out (char byte)

{

  for (unsigned char a=8; a>0; a--)

  {  

    if ( (byte & (1<<(a-1))) != 0)

    {

      PORT_LCD_DATA |= (1<<LCD_DATA); //Data PIN (High)

    }

    else

    {

      PORT_LCD_DATA &= ~(1<<LCD_DATA); //Data PIN (LOW)

    }

    Clock();

  }

  enable();

};

//------------------------------------------------------------------------------

void lcd_print_P (unsigned char zeile,unsigned char spalte,const char *Buffer,...)

{

  va_list ap;

  va_start (ap, Buffer);  

  int format_flag;

  char str_buffer[10];

  char str_null_buffer[10];

  char move = 0;

  char Base = 0;

  int tmp = 0;

  char by;

  char *ptr;

  //Berechnet Adresse für die Zeile und schreibt sie ins DD-Ram

  zeile = LINE_ADDRESS[zeile];

  zeile += spalte;

  lcd_write(zeile,0);

  //Ausgabe der Zeichen

    for(;;)

  {

    by = *(Buffer++);

    if(by==0) break; // end of format string

    if (by == '%')

    {

            by = *(Buffer++);

      if (isdigit(by)>0)

        {

         str_null_buffer[0] = by;

        str_null_buffer[1] = '\0';

        move = atoi(str_null_buffer);

                by = *(Buffer++);

        }

      switch (by)

        {

        case 's':

                    ptr = va_arg(ap,char *);

                    while(*ptr) {lcd_write(*ptr++,1); }

                    break;

        case 'b':

          Base = 2;

          goto ConversionLoop;

        case 'c':

          //Int to char

          format_flag = va_arg(ap,int);

          lcd_write (format_flag++,1); 

          break;

        case 'i':

          Base = 10;

          goto ConversionLoop;

        case 'o':

          Base = 8;

          goto ConversionLoop;

        case 'x':

          Base = 16;

          //****************************

          ConversionLoop:

          //****************************

          itoa(va_arg(ap,int),str_buffer,Base);

          int b=0;

          while (str_buffer[b++] != 0){};

          b--;

          if (b<move)

            {

            move -=b;

            for (tmp = 0;tmp<move;tmp++)

              {

              str_null_buffer[tmp] = '0';

              }

            //tmp ++;

            str_null_buffer[tmp] = '\0';

            strcat(str_null_buffer,str_buffer);

            strcpy(str_buffer,str_null_buffer);

            }

          lcd_char(str_buffer,1);

          move =0;

          break;

        }

      }  

    else

      {

      lcd_write (by,1);

      }

    }

  va_end(ap);

};

//------------------------------------------------------------------------------

void lcd_print_str (char *Buffer)

{

  while (*Buffer != 0)

    {

    lcd_char(*Buffer++,1);

    };

};

//------------------------------------------------------------------------------

void lcd_clear (void)

{

  lcd_write (1,0); //Clear Display

  lcd_write (0x80,0);  //Set DD-Ram Adresse = 0

}