lights.c

/*
 * lights2.c
 *
 * Created: 6/24/2013 10:06:23 PM
 *  Author: dtudury
 */ 

#ifndef F_CPU
#define F_CPU 8000000UL // or whatever may be your frequency
#endif

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

//D3 GRN
//D6 BLU
//B1 RED

static uint16_t meters = 5;
static uint16_t ledsPerMeter = 32;
static uint16_t numLEDs = 5 * 32;
int *pixels;
int *channels;
int channel;

void pwmInit() {
  //https://sites.google.com/site/qeewiki/books/avr-guide/pwm-on-the-atmega328
	//set up red pin on timer 1, B1 (OCR1A)
	TCCR1A = (1 << WGM12) | (1 << WGM10);
	TCCR1A |= (1 << COM1A1) | (1 << COM1A0);
	TCCR1B = (1 << CS10);
	DDRB |= (1 << DDB1);

	//set up green pin on timer 2, D3 (OCR2B)
	TCCR2A = (1 << WGM21) | (1 << WGM20);
	TCCR2A |= (1 << COM2B1) | (1 << COM2B0);
	TCCR2B = (1 << CS20);
	DDRD |= (1<<DDD3);
	
	//set up blue pin on timer 0, D6 (OCR0A)
	TCCR0A = (1 << WGM01) | (1 << WGM00);
	TCCR0A |= (1 << COM0A1) | (1 << COM0A0);
	TCCR0B = (1 << CS00);
	DDRD |= (1<<DDD6);
}

void interruptInit() {
	//set up A pin on D0 (PCINT16)
	DDRD &= ~(1 << DDD0);
	PORTD |= (1 << PORTD0);
	PCMSK2 |= (1 << PCINT16);
	
	//set up B pin on D1 (PCINT17)
	DDRD &= ~(1 << DDD1);
	PORTD |= (1 << PORTD1);
	PCMSK2 |= (1 << PCINT17);

	PCICR |= (1 << PCIE2);
	
	//set up button (SW) on C5 (PCINT13)
	DDRC &= ~(1 << DDC5);
	PORTC |= (1 << PORTC5);
	PCMSK1 |= (1 << PCINT13);

	PCICR |= (1 << PCIE1);

	sei();                     // turn on interrupts
}


uint8_t map(uint8_t v) {
	v++;
	return rand() % (v % 128) | 0b10000000;
}

void writeBit(uint8_t on) {
	if (on) PORTC |= 0b00000010;
	else PORTC &= ~0b00000010;
	
	//toggle clock
	PORTC |= 0b00000001;
	PORTC &= ~0b00000001;
}

void write8(uint8_t d) {
	for (uint8_t i=0; i<8; i++) {
		writeBit(d & _BV(7-i));
	}
}

void show(uint16_t r, uint16_t g, uint16_t b) {
	uint16_t i;
	
	write8(0);
	write8(0);
	write8(0);
	write8(0);

	for (i=0; i<numLEDs; i++ ) {
		write8(map(g / 4));
		write8(map(r / 4));
		write8(map(b / 4));
	}
	for (i=0; i<meters; i++ ) {
		write8(0);
	}
}


int main(void) {
	pwmInit();
	interruptInit();
	DDRC |= 0b00000011;
		
	pixels = (int *)malloc(numLEDs * 3);
	channels = (int *)malloc(3);
	channels[0] = 30;
	channels[1] = 30;
	channels[2] = 30;
	channel = 0;
	updatePin();
	
    while(1) {
		show(channels[0], channels[1], channels[2]);
    }
}


int lastA = 0;
int lastB = 0;
int step = 0;

void inc() {
	channels[channel]++;
}

void dec() {
	channels[channel] += 511;
}

void updatePin() {
	OCR1A = 0;
	OCR2B = 0;
	OCR0A = 0;
	if(channel == 0) {
		OCR1A = (channels[0] / 4) % 128 + 1;
	} else if(channel == 1) {
		OCR2B = (channels[1] / 4) % 128 + 1;
	} else {
		OCR0A = (channels[2] / 4) % 128 + 1; //blue pin
	}

}

ISR (PCINT2_vect) {
	int A = PIND & (1 << PIND0);
	int B = PIND & (1 << PIND1);

	if(A && B) {
		if(!lastA && lastB) {
			inc();
		} else if(lastA && !lastB) {
			dec();
		}
	} else if(A) {
		if(lastA && lastB) {
			inc();
		} else if(!lastA && !lastB) {
			dec();
		}
	} else if(B) {
		if(!lastA && !lastB) {
			inc();
		} else if(lastA && lastB) {
			dec();
		}			
	} else {
		if(lastA && !lastB) {
			inc();
		} else if(!lastA && lastB) {
			dec();
		}
	}

	updatePin();
	
	lastA = A;
	lastB = B;
}

ISR (PCINT1_vect) {
	if(PINC & (1 << PINC5)) {
		channel++;
		channel %= 3;
	}
	updatePin();		
}