Bike cluster

// This #include statement was automatically added by the Particle IDE.
#include <ThingSpeak.h>

int ANALOG_MAG_PIN = A1; //The analog pin for the analog output of the sensor
int DIGITAL_MAG_PIN = D1; //The digital pin for the digital output of the sensor
int Speed; //The speed variable
int timer; //Time Variable 
int totaltime; // The total time declared for magnet to travel
int circumference; //Circumference Variable
int radius= 12; //Radius being declared in inches 
int mag_D; //Variable to store the digital reading
int mag_A; //Variable to store the analog reading
const char * writeKey = "C8KM44MU1C1QYS21"; //Writekey allows for data to be plotted 
unsigned long channel = 1915324;
TCPClient client;



void Start()
 {
      timer++;                        // Begin the timer and start counting
      delayMicroseconds(9600);        // Delay to start after a 0.0096 seconds
 }

void setup() 
{
  Serial.begin(9600); //Start the serial connection to the computer
  
  attachInterrupt(D1, Start, RISING); // Begins the counting when the reading from D1 is Low
  
  pinMode(ANALOG_MAG_PIN, INPUT); //Make the pin you used an input on the Argon
  pinMode(DIGITAL_MAG_PIN, INPUT); //Make the pin you used an input on the Argon
   timer = 0;                                                 // Sets timer to 0 seconds
   Speed = 0;                                                 // sets the speed to 0 seconds
   totaltime = 0;                                             // sets the total time to start off at 0
   circumference = 6.28 * radius;                             // calculated the circumference
    ThingSpeak.begin(client);
  
}

//This code will run infinitely
void loop() 
{
   if (millis() - totaltime >= 1000) {  // Gets varibales to go into the loop everytime the millis() - the total time elapsed is less than 1ms
      detachInterrupt(D1); 
       Speed = ((8.181818182*circumference)/(millis() - totaltime)*timer); // Calculates the speed of the bike. The 8.18 number is converting the time in seconds into hours and inches into feet.
       
        timer = 0;                                                          // Makes the timer go back to zero
        totaltime = millis();                                               // Makes the total time the new time
        attachInterrupt(D1, Start, RISING);             // Make the Start loop attach back

       
  mag_D = digitalRead(DIGITAL_MAG_PIN); //Read the signal from magnetic sensor
  mag_A = analogRead(ANALOG_MAG_PIN); //Read the signal from magnetic sensor
 

  delay(1000); 
  if(mag_D == HIGH)
  {
   
    Particle.publish("Speed", String(Speed),ALL_DEVICES); //Publishes the velocity of the bike in MPH
    ThingSpeak.setField(1, Speed);
    ThingSpeak.writeFields(channel, writeKey);
    
    
  }
  else
  {
      int speed=0;
       Particle.publish("Speed", String(Speed),ALL_DEVICES); //Publishes the velocity of the bike in MPH
    ThingSpeak.setField(1, Speed);
    ThingSpeak.writeFields(channel, writeKey);
  }
   }
  
}