/*
Based on Arduino sketch for simulating a Canon RC-1 IR remote control to start and stop video recording on a Canon 5D Mark II or 7D
 2010, Martin Koch
 http://controlyourcamera.blogspot.com/
 Huge thanks go to http://www.doc-diy.net/photo/rc-1_hacked/index.php for figuring out the IR code.
 
 Modified by JustinHerx for accepting input from a remote (wired/wireless) and turning the
 output into an IR command to activate/deactivate video recording on a Canon 5D MII, 7D, 60D, etc.
 Parts required:
 - Arduino
 - Power LED (or switch with power LED, I am using an illuminated pushbutton switch from RadioShack # 275-0009)
 - Piezo buzzer (RadioShack #273-059)
 - 2.5mm jack to attach camera trigger
 - IR LED to trigger camera
 - Resistor for LED
 */

const int irLED = 11;
const int SWITCH = 7;
const int buzzPin = 8;
const int powerLED = 4;
boolean running = false;
int ledState = HIGH;             // ledState used to set the LED
long previousMillis = 0;        // will store last time LED was updated
long interval = 200;           // interval at which to blink (milliseconds)

unsigned int pulseDuration = 10; //microseconds 
//The required 15 microseconds pulseDuration didn't work since digitalWrite consumes some additional time
//thats adds to pulseDuration value. 10 to 12 microseconds worked for me.

unsigned int photo = 7330; //A 7330 microseconds delay between bursts shoots a photo.
unsigned int video = 5360; //A 5360 microseconds delay between bursts starts/stops video recording. 

void setup() {
  //Serial.begin(9600); // uncomment for debugging
  pinMode(irLED, OUTPUT);
  pinMode(SWITCH, INPUT);
  pinMode(buzzPin, OUTPUT);
  pinMode(powerLED, OUTPUT);
  digitalWrite(SWITCH, HIGH); //turn on internal 20 k pullup resistor so the open input state is HIGH.
  digitalWrite(buzzPin, LOW);
  digitalWrite(powerLED, HIGH);

}

void loop() { //run again and again 

  if (running == true) // This part of the loop is to test if the camera has been triggered to record 
    // and blinks the power LED while recording.
  {

    //Serial.print("running"); //uncomment for debugging
    //Serial.println();

    unsigned long currentMillis = millis();

    if(currentMillis - previousMillis > interval) {
      // save the last time you blinked the LED 
      previousMillis = currentMillis;   

      // if the LED is off turn it on and vice-versa:
      if (ledState == LOW)
      {
        ledState = HIGH;
      }
      else
      {
        ledState = LOW;
      }
      // set the LED with the ledState of the variable:
      digitalWrite(powerLED, ledState);
    }
  }

  if (digitalRead(SWITCH) == LOW) { //read switch input
    shoot(video); //start or stop video recording
    if (running == false)  //detect the state of recording and invert it
    {
      running = true;
    }
    else
    {
      running = !running;
      digitalWrite(powerLED, HIGH);
    }
    piezoBeep(); //beep the buzzer to indicate that recording has started or stopped
    delay(500);
  }
}

void shoot(unsigned int delayBetweenBursts) { //sends the IR signal

  //send first 16 bursts
  for(int i=0; i<16; i++) { 
    digitalWrite(irLED, HIGH);
    delayMicroseconds(pulseDuration);
    digitalWrite(irLED, LOW);
    delayMicroseconds(pulseDuration);
  } 

  delayMicroseconds(delayBetweenBursts); 

  //send second 16 bursts
  for(int i=0; i<16; i++) { 
    digitalWrite(irLED, HIGH);
    delayMicroseconds(pulseDuration);
    digitalWrite(irLED, LOW);
    delayMicroseconds(pulseDuration);
  } 
  return;
}

void piezoBeep(){ //beeps the piezo buzzer, once for start of recording, twice for end of recording
  if (running == true)
  {
    digitalWrite(buzzPin, HIGH);
    delay(250);
    digitalWrite(buzzPin, LOW);
  }
  else
  {
    digitalWrite(buzzPin, HIGH);
    delay(250);
    digitalWrite(buzzPin, LOW);
    delay(100);
    digitalWrite(buzzPin, HIGH);
    delay(250);
    digitalWrite(buzzPin, LOW);
  }
}