Lab 6

int delayLength = 200;
int notes[4] = {50, 55, 60, 65};
int LEDPins[4] = { 7, 8, 9, 10 };

int currentStep = 0;

int noteOffset = 0;

unsigned long lastStepTime;

void setup() {
  Serial.begin(9600);

  //Set pinMode for outputs (Pins 7,8,9,10)
  
  for (int i = 0; i < sizeof(LEDPins); i++) {

    pinMode(LEDPins[i], OUTPUT); //+7 offsets the pin number to start at 7
    
  }

  //Set inputs' pinMode
  for (int i = 0; i < 3; i++) {

    pinMode(i+37, INPUT); //Same offset but for 37 for setting inputs
    
  } 

}

void loop() {

  //Get delayLength by reading from pin 13 and mapping it between 100 and 1000
  delayLength = map(analogRead(13), 0, 1023, 100, 1000);

  //Get the pot values for each step, add to notes array
  for (int i = 0; i < 4; i++) {

    notes[i] = map(analogRead(i+33), 0, 1023, 60, 72); //Allows values between 60 and 72
    
  }

  //If pin 37 is high, add offset
    if (digitalRead(37) == HIGH) {
      noteOffset = 12;
    } else {
      noteOffset = 0;
    }
  
  stepEither();

}

void stepEither() {
  
  if (millis() > lastStepTime + delayLength) {

    lastStepTime = millis();
    
    digitalWrite(LEDPins[currentStep], LOW);

    //Send noteOff to every possible note to avoid getting stuck while changing note/octave
    for (int i = 60; i <= 84; i++){
      usbMIDI.sendNoteOff(i, 0, 1);
    }

    if (digitalRead(39) == HIGH) {
      currentStep++;
      if (currentStep >= 4) {
        currentStep = 0;
      }
    } else {

      currentStep--;
      if (currentStep < 0) {
        currentStep = 3;
      }
      
    }
    

    digitalWrite(LEDPins[currentStep], HIGH);
    
    usbMIDI.sendNoteOn(notes[currentStep] + noteOffset, 127, 1); //Send note on
    
  }
  
}