led.cpp

/*
 *
 */

#include <Arduino.h>
#include <math.h>
#include "led.h"

extern uint32_t MILLIS;


/*
 *
 */
led::led(int ledPin) {
    ledInit(ledPin, 255);
}


/*
 *
 */
led::led(int ledPin, int pwmMax) {
    ledInit(ledPin, pwmMax);
}


void led::loop() {
    switch (mode) {

        case BLINK:
            if (MILLIS - timer >= period >> 1) {  // Quick divide by 2
                timer = MILLIS;
                duty = pwmMax * not duty;
            }
            break;

        /*
         * This is sorta complicated. We flash flashes times with
         * the given period. Then we turn off for wait ms. Then we
         * start over by resetting the timer.
         *
         * Uses the fact that odd multiples of half period should be ON
         */
        case FLASH:
            if (MILLIS - timer >= period * flashes + wait) {
                timer = MILLIS;
            } else if (MILLIS - timer >= period * flashes) {
                duty = 0;
            } else if ((2 * (MILLIS - timer) / period) % 2) {
                duty = pwmMax;
            } else {
                duty = 0;
            }
            break;

        /* "Breathe" by half the cycle of sin(x */
        case PULSE:
            duty = pwmMax * sin(fmod(MILLIS, period) * PI / (float)period);
            break;

        case SOLID:
            duty = pwmMax;
            break;

        case STOP:
            duty = 0;
            break;
    }  // switch

    analogWrite(ledPin, duty);
}


/*
 *
 */
bool led::isOn() {
    return duty > 0;
}


/*
 * mode
 *     One of the led modes enumerated in led.h
 */
void led::setMode(mode_t mode) {
    setMode(mode, this->period, this->flashes, this->wait);
}


/*
 * mode
 *     One of the led modes enumerated in led.h
 *
 * period
 *     Period of cyclic functions, in milliseconds
 */
void led::setMode(mode_t mode, uint32_t period) {
    setMode(mode, period, this->flashes, this->wait);
}


/*
 * mode
 *     One of the led modes enumerated in led.h
 *
 * period
 *     Period of cyclic functions, in milliseconds
 *
 * flashes
 *     Number of flashes during FLASH mode
 *
 * wait
 *     Time between each burst of flashes in FLASH mode (ms)
 */
void led::setMode(mode_t mode, uint32_t period, int flashes, uint32_t wait) {
    this->mode    = mode;
    this->period  = period;
    this->flashes = flashes;
    this->wait    = wait;
}


/*
 *
 */
void led::setOff() {
    setMode(STOP);
}


/*
 *
 */
void led::phaseInvert() {
    timer += period / 2;
}


void led::ledInit(int ledPin, int pwmMax) {
    this->ledPin  = ledPin;
    this->pwmMax  = pwmMax;
    this->mode    = mode;
    this->period  = 1000;
    this->flashes = 1;
    this->wait    = 0;

    timer = 0;
    duty  = 0;

    pinMode(ledPin, OUTPUT);
}