Transmitter

#include <SPI.h>
#include <nRF24L01.h>
#include <RF24.h>

RF24 radio(A0,A1);

const byte address[6] = "00001";

void setup() {
  radio.begin();
  radio.openWritingPipe(address);
  radio.setPALevel(RF24_PA_MAX);
  radio.setDataRate(RF24_250KBPS);
  radio.stopListening();
}

void loop() {
  const byte mynum = 1;
  radio.write(&mynum, sizeof(mynum));
  delay(2000);
}