Arduino file for a 2 digit remote controlled lap counter with a nrf24L - controller

remote.ino

#include <Keypad.h>

const byte ROWS = 4; 
const byte COLS = 3; 

#include <TM1637Display.h>

const int CLK = 3; //Set the CLK pin connection to the display
const int DIO = 2; //Set the DIO pin connection to the display


int NumStep = 0;  //Variable to interate

TM1637Display display(CLK, DIO);  //set up the 4-Digit Display.

char hexaKeys[ROWS][COLS] = {
  {'1', '2', '3'},
  {'4', '5', '6'},
  {'7', '8', '9'},
  {'*', '0', '#'}
};

byte rowPins[ROWS] = {7, 15, 16, 18};
byte colPins[COLS] = {19, 8, 17}; 

// NRF
#include "nRF24L01.h" //NRF24L01 library created by TMRh20 https://github.com/TMRh20/RF24
#include "RF24.h"
#include "SPI.h"
RF24 radio(9,10);
const uint64_t pipe = 0xE6E6E6E6E6E6; // Needs to be the same for communicating between 2 NRF24L01 
int number = -1;
int number2 = -1;

Keypad customKeypad = Keypad(makeKeymap(hexaKeys), rowPins, colPins, ROWS, COLS); 

void setup(){
  Serial.begin(9600);
  display.setBrightness(0x0a);  //set the diplay to maximum brightness
  radio.begin(); // Start the NRF24L01
  radio.openWritingPipe(pipe); // Get NRF24L01 ready to transmit
  radio.setPALevel(RF24_PA_MAX); // RF24_PA_LOW, RF24_PA_HIGH, RF24_PA_MAX, RF24_PA_ERROR
}
  
void loop(){
  char customKey = customKeypad.getKey();
  
  if (customKey){
    //Serial.println(customKey);
    
    if(customKey == 35){
      Serial.print(number);
      radio.write(&number, sizeof(int));
    } else if(customKey == 42) {
      if(number > -1){
        number--;
      }
      display.showNumberDec(number);
      radio.write(&number, sizeof(int));
    } else {
        if(number >= 10){
          number = -1;
        }
        if(number > 0){
          number = (customKey - 48) + number * 10;
        } else {
          number = customKey - 48; 
        } 
      display.showNumberDec(number);
    }
  }
}