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Embedded C code for Three 7 Segment displays


Sample code for Three 7 Segment displays using delay subroutine.
Following code can be using for AVR series ICs like: ATmega8, ATmega16, ATmega32. 

 

#include <avr/io.h>
#include <util/delay.h>

#define	DISPLAY_PORT	PORTD
#define	DISPLAY_DDR		DDRD

#define	DISPLAY_CTRL_PORT	PORTB
#define	DISPLAY_CTRL_DDR	DDRB

#define	ZERO       0x77 
#define	ONE        0x41
#define	TWO        0x3B
#define	THREE      0x6B
#define	FOUR       0x4D
#define	FIVE       0x6E
#define	SIX        0x7E
#define	SEVEN      0x43
#define	EIGHT      0x7F
#define	NINE       0x6F
#define	DOT        0x80

#define	DIGIT1				4	//(left most)
#define	DIGIT2				5
#define	DIGIT3				6
#define	DIGIT4				7	//(right most)


#ifndef cbi
#define cbi(sfr, bit) (_SFR_BYTE(sfr) &= ~_BV(bit))
#endif

#ifndef sbi
#define sbi(sfr, bit) (_SFR_BYTE(sfr) |= _BV(bit))
#endif

int main(void)
{
	int i=0;
	int d1,d2,d3;
	int disp1,disp2,disp3;
	
	DISPLAY_DDR=0xFF;
	DISPLAY_PORT=0x00;
	
	DISPLAY_CTRL_DDR=0xff;
	DISPLAY_CTRL_PORT=0x00;	
	
	_delay_ms(4000);
	
	while(1)
	{
	
		for(d1=0;d1<10;d1++)
		{
			for(d2=0;d2<10;d2++)
			{
				for(d3=0;d3<10;d3++)
				{
				
					for(i=0;i<1000;i++)
					{
						

						switch(d1)
						{
						    case 0:
							disp1=~ZERO;
							break;
						    case 1:
							disp1=~ONE;
							break;
						    case 2:
							disp1=~TWO;
							break;
						    case 3:
							disp1=~THREE;
							break;
						    case 4:
							disp1=~FOUR;
							break;
						    case 5:
							disp1=~FIVE;
							break;
						    case 6:
							disp1=~SIX;
							break;
						    case 7:
							disp1=~SEVEN;
							break;
						    case 8:
							disp1=~EIGHT;
							break;
						    case 9:
							disp1=~NINE;
							break;		
						}
						

						switch(d2)
						{
						    case 0:
							disp2=~ZERO;
							break;
						    case 1:
							disp2=~ONE;
							break;
						    case 2:
							disp2=~TWO;
							break;
						    case 3:
							disp2=~THREE;
							break;
						    case 4:
							disp2=~FOUR;
							break;
						    case 5:
							disp2=~FIVE;
							break;
						    case 6:
							disp2=~SIX;
							break;
						    case 7:
							disp2=~SEVEN;
							break;
						    case 8:
							disp2=~EIGHT;
							break;
						    case 9:
							disp2=~NINE;
							break;		
						}
		

						switch(d3)
						{
						    case 0:
							disp3=~ZERO;
							break;
						    case 1:
							disp3=~ONE;
							break;
						    case 2:
							disp3=~TWO;
							break;
						    case 3:
							disp3=~THREE;
							break;
						    case 4:
							disp3=~FOUR;
							break;
						    case 5:
							disp3=~FIVE;
							break;
						    case 6:
							disp3=~SIX;
							break;
						    case 7:
							disp3=~SEVEN;
							break;
						    case 8:
							disp3=~EIGHT;
							break;
						    case 9:
							disp3=~NINE;
							break;		
						}
		
						
					sbi(DISPLAY_CTRL_PORT,DIGIT1);
					cbi(DISPLAY_CTRL_PORT,DIGIT2);
					cbi(DISPLAY_CTRL_PORT,DIGIT3);
					DISPLAY_PORT=disp3;
					_delay_us(200);
			
					cbi(DISPLAY_CTRL_PORT,DIGIT1);
					sbi(DISPLAY_CTRL_PORT,DIGIT2);
					cbi(DISPLAY_CTRL_PORT,DIGIT3);
					DISPLAY_PORT=disp2;
					_delay_us(200);
						
					cbi(DISPLAY_CTRL_PORT,DIGIT1);
					cbi(DISPLAY_CTRL_PORT,DIGIT2);
					sbi(DISPLAY_CTRL_PORT,DIGIT3);
					DISPLAY_PORT=disp1;
					_delay_us(200);
					}
					
				}
			
			}
		
		}
	
	}	
	return 0;
}