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"

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);

  NOP();

  NOP();

  PORT_LCD_DATA_ENABLE &= ~(1<<LCD_DATA_ENABLE);

}

void Clock (void)

{

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

  NOP();

  NOP();

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

}

void shift_out(char data, char cd)

{

  unsigned int h_nibble;

  unsigned int l_nibble;

  h_nibble |= (data & 0xF0)>>1;

  Clock();

  shift_data_out(h_nibble);

  enable();

  l_nibble|= (data&0x0F)<<3;

  Clock();

  shift_data_out(l_nibble);

  enable();

}

void lcd_init (void)

{  

  //Set Port Direction Register

  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);

  //Wait a short Time afer Power on  

  WAIT(20);

  lcd_clear();

  enable();

  for (unsigned char a=0;a<3;a++)

    {

    shift_out() (0x22,0);  //Init in 4 Bit Mode

    WAIT(5);

    enable();

    }

  WAIT(10);

  lcd_write(0x80,0);

  Clock();

  enable();  

  WAIT(10);  

  lcd_write(0x80,0);

  Clock();

  enable();

  WAIT(10);

#ifdef ONE_LINES

  lcd_write (0x22,0);  //1 Zeilen

  enable();

#else

  lcd_write (0x28,0);  //mehrere Zeilen

  enable();

#endif

  lcd_write (0xD0,0);  //Display On

  enable();

}

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

void lcd_write (char data,char cd)

{

  WAIT(BUSY_WAIT_US);

  unsigned char h_byte = 0;

  unsigned char l_byte = 0;

  //Soll ins Seuer oder Datenregister geschrieben werden?

  if(cd)

  {

    h_byte |= (1<<LCD_RS_PIN);

    l_byte |= (1<<LCD_RS_PIN);

  }

  if(back_light)

  {

    h_byte |= (1<<LCD_LIGHT_PIN);

    l_byte |= (1<<LCD_LIGHT_PIN);

  }

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

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

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

  shift_data_out(h_byte);

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

  shift_data_out(l_byte);

}

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

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 = pgm_read_byte(Buffer++);

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

    if (by == '%')

    {

            by = pgm_read_byte(Buffer++);

      if (isdigit(by)>0)

        {

         str_null_buffer[0] = by;

        str_null_buffer[1] = '\0';

        move = atoi(str_null_buffer);

                by = pgm_read_byte(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_print_str (str_buffer);

          move =0;

          break;

        }

      }  

    else

      {

      lcd_write (by,1);

      }

    }

  va_end(ap);

}

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

void lcd_print_str (char *Buffer)

{

  while (*Buffer != 0)

    {

    lcd_write (*Buffer++,1);

    };

}

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

void lcd_clear (void)

{

  lcd_write (1,0); //Clear Display

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

}