// CPU frequency 9.6MHz
// Temperature sensor (TMP36) on ADC3 (PB3)
// MosFet output on OC0A (PB0)

int main(void) {
	int16_t t;
	
	ADMUX = 0x43;	// internal reference, right adjust, ADC3
	ADCSRA = 0x87;	// ADC enable, prescaler to 128 (175us/conv.)
	
	TCCR0A = 0x83;	// fast pwm on OC0A
	TCCR0B = 0x01;	// prescaler to 1 => f=37.5kHz
	
	while(1) {
		ADCSRA |= 0x40;			// start conversion
		while(ADCSRA & 0x40);		// wait for completion
		
		t = ADC - 665;
		t *= 49;			// approx.
		t /= 32;			// 1.6451
		
		if(t < 0) t = 0;		// limits
		if(t > 255) t = 255;		//
		
		OCR0A = t;
	}
	
	return 0;
}