labb_03_code_01.c

/*
ATmega8, 48, 88, 168, 328

/Reset PC6|1   28|PC5
       PD0|2   27|PC4
       PD1|3   26|PC3       LCD_RW ( 6)
       PD2|4   25|PC2       LCD_E  ( 5)
       PD3|5   24|PC1       LCD_RS ( 3)
       PD4|6   23|PC0
       Vcc|7   22|Gnd
       Gnd|8   21|Aref
       PB6|9   20|AVcc
       PB7|10  19|PB5 SCK   LCD_D7 (13)
       PD5|11  18|PB4 MISO  LCD_D6 (14)
       PD6|12  17|PB3 MOSI  LCD_D5 (11)
       PD7|13  16|PB2       LCD_D4 (12)
       PB0|14  15|PB1
*/

#define F_CPU 1000000UL  // 1 MHz standard clock

#include <avr/io.h>
#include <stdlib.h>
#include <stdio.h>
#include <util/delay.h>
#include "lcd.h"

/*
  lcd_printbinary(arg, bits);
  prints a binary number on the LCD
   - arg  unsigned integer value to be printed
   - bits number of bits to be printed, leading zeros are printed
*/

void lcd_printbinary(uintmax_t arg, uint8_t bits)
{
  int8_t i=bits;
  while (i>0)
  {
    i--;
    if (arg & (1 << i))
    {
      lcd_putc('1');
    }
    else
    {
      lcd_putc('0');
    }
  }
}

int main(void)
{
  lcd_init(LCD_DISP_ON); // initialize LCD
  lcd_clrscr();          // clear screen

  DDRD  = 0;             // all pins input on port D
  PORTD = 0xff;          // all pull-ups active on port D

  while (1)
  {
    _delay_ms(2);             // short delay
    lcd_gotoxy(0,0);          // start at upper left corner
    lcd_puts("0b");           // leading C-style identifier
    lcd_printbinary(PIND, 8); // print value of PIND
  }
}