/* Ping))) Sensor

This sketch reads a PING))) ultrasonic rangefinder and returns the
distance to the closest object in range. To do this, it sends a pulse
to the sensor to initiate a reading, then listens for a pulse
to return. The length of the returning pulse is proportional to
the distance of the object from the sensor.
*/

#include <Wire.h>
#include "Adafruit_LEDBackpack.h"
#include "Adafruit_GFX.h"
Adafruit_7segment matrix = Adafruit_7segment();
int triggerPin = 5;
int echoPin = 6;
long duration = 0;
float cm = 0.0;


void setup() {
  Serial.begin(9600);
  matrix.begin(0x70);
  pinMode(triggerPin, OUTPUT);
  pinMode(echoPin, INPUT);

}

void loop(){
//Inputs:
digitalWrite(triggerPin,LOW);
delayMicroseconds(5);
digitalWrite(triggerPin,HIGH);
delayMicroseconds(5);
digitalWrite(triggerPin,LOW);
delayMicroseconds(5);
duration=pulseIn(echoPin, HIGH);
//if(cm >=  20){
//Serial.println("youre a little too close");
//}
//else{
//Serial.println("I like nice people and programs. Do you?");
//}


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



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

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