/*
  AnalogReadSerial

  Reads an analog input on pin 0, prints the result to the Serial Monitor.
  Graphical representation is available using Serial Plotter (Tools > Serial Plotter menu).
  Attach the center pin of a potentiometer to pin A0, and the outside pins to +5V and ground.

  This example code is in the public domain.

  https://www.arduino.cc/en/Tutorial/BuiltInExamples/AnalogReadSerial
*/

unsigned long currentTime;
unsigned long detectTime = 0;
unsigned long elapsedTime = 0;

int oldSensVal = 1; //initialize sensor value 
int count = 0; //initialize count of magnet passes 

bool stopped;

void setup() {
  Serial.begin(9600); //start serial communication
  pinMode(3, OUTPUT);
  pinMode(4, OUTPUT);
}

void loop() {

  int sensorValue = digitalRead(2);  //read sensor value, save as 'sensorValue'

  currentTime = millis();

  if (sensorValue==0 && sensorValue!=oldSensVal){  //if sensor value is 0, i.e. detects magnet
    stopped=false;
    elapsedTime=currentTime-detectTime;
    detectTime=currentTime;
    count++;  //count that as an additional count for magnet passed
/*
    Serial.print("Time in MSec: ");
    Serial.print(currentTime);
    Serial.print(" .. ");
    Serial.print(count);
    Serial.print(" detection... and ");
    Serial.print(elapsedTime);
    Serial.println(" milliseconds passed since last detection.");
    Serial.print("This means: ");
*/
    Serial.println(360000/elapsedTime);

/*  
    Serial.println(" degrees per second");
    Serial.println("-----------------------------------");
*/

    digitalWrite(3,HIGH);
    digitalWrite(4,HIGH);
  }
  else if (sensorValue==0 && sensorValue==oldSensVal){  //otherwise..
    digitalWrite(3,HIGH);
    digitalWrite(4,HIGH);
  }
  else{
    digitalWrite(3,LOW);
    digitalWrite(4,LOW);
  }
  delay(10);  //delay period (ms)
  oldSensVal = sensorValue;  //set currentvalue as the previous value 


  if ((currentTime-detectTime)>=800 && stopped==false){
    Serial.println(0);
    stopped=true;
  }


}