Radio communication between two arduinos

//transmitter code (ULTRASONIC RANGER)

#include <SPI.h>

#include <nRF24L01.h>

#include <RF24.h>

#include <NewPing.h>

#define TRIGGER_PIN  4  // Arduino pin tied to trigger pin on the ultrasonic sensor.

#define ECHO_PIN     3  // Arduino pin tied to echo pin on the ultrasonic sensor.

#define MAX_DISTANCE 50 // Maximum distance we want to ping for (in centimeters). Maximum sensor distance is rated at 400-500cm.

NewPing sonar(TRIGGER_PIN, ECHO_PIN, MAX_DISTANCE); // NewPing setup of pins and maximum distance.

RF24 radio(7, 8); // CE, CSN

const byte address[6] = "12345";

void setup() {

  radio.begin();

  radio.openWritingPipe(address);

  radio.setPALevel(RF24_PA_LOW);

  radio.stopListening();

  Serial.begin(9600);

}

void loop() {

  int sendVal = sonar.ping_cm();

  radio.write(&sendVal, sizeof(sendVal));

  delay(50);                     // Wait 50ms between pings (about 20 pings/sec). 29ms should be the shortest delay between pings.

  //Serial.print("Ping: ");

  Serial.println(sendVal); // Send ping, get distance in cm and print result (0 = outside set distance range)

  //Serial.println("cm");

}

//receiver code (SERVO MOTOR)

#include <SPI.h>

#include <nRF24L01.h>

#include <RF24.h>

#include <Servo.h>

Servo gaugeMotor;

RF24 radio(7, 8); // CE, CSN

const byte address[6] = "12345";

const int MOTORPIN = 3;

int sendVal, motorPos;

void setup() {

  Serial.begin(9600);

  radio.begin();

  radio.setPALevel(RF24_PA_LOW);

  radio.startListening();

  radio.openReadingPipe(1, address);

  gaugeMotor.attach(MOTORPIN);

}

void loop() {

  if (radio.available()) {

    radio.read(&sendVal, sizeof(sendVal));

    Serial.println(sendVal);

    motorPos = map(sendVal, 0, 50, 10, 170);

    gaugeMotor.write(motorPos);

    delay(10);

  }

}