#include <Wire.h>
#include "Adafruit_LEDBackpack.h"
#include "Adafruit_GFX.h"
Adafruit_7segment matrix = Adafruit_7segment();
int triggerPin = 5;
int echoPin = 7;
int declare = 0;
long duration = 0;
float in = 0;

void setup() {
Serial.begin(115200);
matrix.begin(0x70);
pinMode (triggerPin, OUTPUT);
pinMode (echoPin, INPUT);

}

void loop(){
digitalWrite(triggerPin, LOW);
delayMicroseconds(5);
digitalWrite(triggerPin, HIGH);
delayMicroseconds(5);
digitalWrite(triggerPin, LOW);
delayMicroseconds(5);

//Inputs:
duration = pulseIn(echoPin, HIGH);



// Calculations: convert the time into a distance
  in = duration /29.0 / 2.0;



//Outputs
  Serial.print(in);
  Serial.print("in");
  Serial.println();

  matrix.print(in);
  matrix.writeDisplay();
  delay(400);
}