app.c

AVR Devolpment Board

#include "avr/io.h"
#include "avr/pgmspace.h"
#include "avr/interrupt.h"
/* FCPU : 1Mhz
 * CPU  : ATMega16 */


const prog_char SIN[]={
128,131,134,137,140,143,146,149,152,155,158,162,165,167,170,173,
176,179,182,185,188,190,193,196,198,201,203,206,208,211,213,215,
218,220,222,224,226,228,230,232,234,235,237,238,240,241,243,244,
245,246,248,249,250,250,251,252,253,253,254,254,254,255,255,255,
255,255,255,255,254,254,254,253,253,252,251,250,250,249,248,246,
245,244,243,241,240,238,237,235,234,232,230,228,226,224,222,220,
218,215,213,211,208,206,203,201,198,196,193,190,188,185,182,179,
176,173,170,167,165,162,158,155,152,149,146,143,140,137,134,131,
128,124,121,118,115,112,109,106,103,100, 97, 93, 90, 88, 85, 82,
 79, 76, 73, 70, 67, 65, 62, 59, 57, 54, 52, 49, 47, 44, 42, 40,
 37, 35, 33, 31, 29, 27, 25, 23, 21, 20, 18, 17, 15, 14, 12, 11,
 10,  9,  7,  6,  5,  5,  4,  3,  2,  2,  1,  1,  1,  0,  0,  0,
  0,  0,  0,  0,  1,  1,  1,  2,  2,  3,  4,  5,  5,  6,  7,  9,
 10, 11, 12, 14, 15, 17, 18, 20, 21, 23, 25, 27, 29, 31, 33, 35,
 37, 40, 42, 44, 47, 49, 52, 54, 57, 59, 62, 65, 67, 70, 73, 76,
 79, 82, 85, 88, 90, 93, 97,100,103,106,109,112,115,118,121,124};


void TimerConfig(void)
{
	/* WGM[1;0]=[1,1] : Fast PWM
	 * COM[1;0]=[1,1] : Set OC0 on compare match, clear OC0 at BOTTOM
	 * CS0[2:0]=[0,1,0] : Clock=FCPU/8 (From prescaler) */
	TCCR0=(1<<WGM00)|(1<<WGM01)|(1<<COM01)|(1<<COM00)|(0<<CS02)|(1<<CS01)|(0<<CS00);

	/* Set the value of Timer/Counter Register to 0 */
	TCNT0= 0x00;

	/* Set the value of Output Compare Register to half of the top(255) value */
	OCR0 = 127;

	/* Enable the tim0 ISR */
	TIMSK|=(1<<OCIE0);

	/* Enable the ISR */
	sei();
}


int main(void)
{
	/* Set LED and Seg LE pin as output , databus as output */
	DDRA |=(1<<PA4)|(1<<PA5)|(1<<PA6); 
	DDRB  = 0xFF;

	/* Off the Seg display */
	PORTB = 0x00;
	PORTA|=  (1<<PA4)|(1<<PA5);
	PORTA&=~((1<<PA6)|(1<<PA5));

	/* Off the led and enable the Led LE */
	PORTB = 0xFF;
	PORTA|= (1<<PA6);

	TimerConfig();
	while(1)
	{
		;
	}
	return 0;
}

SIGNAL(TIMER0_COMP_vect)
{
	static unsigned char x_LUT=0;
	OCR0=pgm_read_byte(&SIN[x_LUT++]);	
}