IRCode.c

/* Blinker Demo */

// ------- Preamble -------- //
#include <avr/io.h>                        /* Defines pins, ports, etc */
#include <util/delay.h>                     /* Functions to waste time */
#define F_CPU 8000000
#define SYSCLOCK F_CPU

#	define TIMER_PWM_PIN  9              // Arduino Duemilanove, Diecimila, LilyPad, etc

# define IR_USE_TIMER1     // tx = pin 9

# define ENABLE_OUTPUT (DDRB |= (1 << PB1))
#define IR

void sendRaw (unsigned int buf[],  unsigned char len,  unsigned char hz);


int main(void) {
int khz=38; 

unsigned int rawData[5] = {796, 180,45, 12,0};

  // -------- Inits --------- //
	ENABLE_OUTPUT;

  // ------ Event loop ------ //
  while (1) {
	
		sendRaw(rawData, sizeof(rawData) / sizeof(int), khz);

  }                                                  /* End event loop */
  return (0);                            /* This line is never reached */
}

#ifdef IR

//---------------------------------------------------------
// Timer1 (16 bits)
//
#elif defined(IR_USE_TIMER1)

#define TIMER_RESET
#define TIMER_ENABLE_PWM   (TCCR1A |= _BV(COM1A1))
#define TIMER_DISABLE_PWM  (TCCR1A &= ~(_BV(COM1A1)))

//-----------------
#	define TIMER_ENABLE_INTR   (TIMSK |= _BV(OCIE1A))
#	define TIMER_DISABLE_INTR  (TIMSK &= ~_BV(OCIE1A))

//-----------------
#define TIMER_INTR_NAME       TIMER1_COMPA_vect

#define TIMER_CONFIG_KHZ(val) ({ \
	const uint16_t pwmval = SYSCLOCK / 2000 / (val); \
	TCCR1A                = _BV(WGM11); \
	TCCR1B                = _BV(WGM13) | _BV(CS10); \
	ICR1                  = pwmval; \
	OCR1A                 = pwmval / 3; \
})

#define TIMER_CONFIG_NORMAL() ({ \
	TCCR1A = 0; \
	TCCR1B = _BV(WGM12) | _BV(CS10); \
	OCR1A  = SYSCLOCK * USECPERTICK / 1000000; \
	TCNT1  = 0; \
})

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

void delayMicroseconds(int time){
	_delay_ms(time);
}

void sendRaw (unsigned int buf[],  unsigned char len,  unsigned char hz)
{
	// Set IR carrier frequency
	enableIROut(hz);

	for (unsigned char i = 0;  i < len;  i++) {
		if (i & 1)  space(buf[i]) ;
		else        mark (buf[i]) ;
	}

	space(0);  // Always end with the LED off
}


void enableIROut (int khz)
{
	// Disable the Timer2 Interrupt (which is used for receiving IR)
	TIMER_DISABLE_INTR; //Timer2 Overflow Interrupt

	ENABLE_OUTPUT; // Enable output on PWM PIN
	PORTB = 0b00000000;          /* Turn off all B pins, including LED */
	// When not sending PWM, we want it low

	// COM2A = 00: disconnect OC2A
	// COM2B = 00: disconnect OC2B; to send signal set to 10: OC2B non-inverted
	// WGM2 = 101: phase-correct PWM with OCRA as top
	// CS2  = 000: no prescaling
	// The top value for the timer.  The modulation frequency will be SYSCLOCK / 2 / OCR2A.
	TIMER_CONFIG_KHZ(khz);
}


//+=============================================================================
// Sends an IR mark for the specified number of microseconds.
// The mark output is modulated at the PWM frequency.
//
void  mark (int time)
{
	TIMER_ENABLE_PWM; // Enable pin 3 PWM output
	if (time > 0) delayMicroseconds(time);
}

//+=============================================================================
// Leave pin off for time (given in microseconds)
// Sends an IR space for the specified number of microseconds.
// A space is no output, so the PWM output is disabled.
//
void  space (int time)
{
	TIMER_DISABLE_PWM; // Disable pin 3 PWM output
	if (time > 0) delayMicroseconds(time);
}

#endif