//EncoderTest
//Counts pulses and LED lights with encoder inputs
//Note - distance traveled is 3.25 mm per pulse

int encLpin = 8;  
int LEDpinL = 9;
int encRpin = 7;  
int LEDpinR = 6;

void setup()
{
  pinMode(encLpin, INPUT);
  pinMode(encRpin, INPUT);
  pinMode(LEDpinL, OUTPUT);    
  pinMode(LEDpinR, OUTPUT);    
  Serial.begin(9600);
}

void loop()  //repeating code
{
  static int encLcount = 0;
  static int encRcount = 0;

  //read encoder pins
  byte encL = digitalRead(encLpin);
  byte encR = digitalRead(encRpin);

  //countPulses
  int addPulseL = countPulse(encLpin);
  int addPulseR = countPulse(encRpin);

  encLcount = encLcount + addPulseL;
  encRcount = encRcount + addPulseR;

  //Light LEDs
  lightLED(LEDpinL, encL);
  lightLED(LEDpinR, encR);

  //Display pulse count to monitor
  Serial.print(encLcount);
  Serial.print("  ");
  Serial.println(encRcount);
  delay(50);
}

void lightLED (int LEDpin, byte encPin)
{
  if (encPin == HIGH)
  {
    digitalWrite(LEDpin, HIGH);
  }
  else
  {
    digitalWrite(LEDpin, LOW);
  }
}


int countPulse (byte encPin) 
{
  byte lastRead = 0;
  static byte lastReadL = 0;
  static byte lastReadR = 0;
  byte addPulse = 0;

  byte encRead = digitalRead(encPin);

  if (encPin == encLpin)   //is this L or R
  {
    lastRead = lastReadL;  
  }
  else 
  {
    lastRead = lastReadR; 
  }

  if (encRead != lastRead)    //if encRead changed
  {
    addPulse = 1;
    lastRead = !lastRead;
  }
  else
  {
    addPulse = 0;
  }

  if (encPin == encLpin) 
  {
    lastReadL = lastRead;  
  }
  else 
  {
    lastReadR = lastRead; 
  }
  
  return (addPulse);

}