code an libraries is here:
https://create.arduino.cc/projecthub/muhammad-aqib/nrf24l01-interfacing-with-arduino-wireless-communication-0c13d4
#include <SPI.h>
#include <nRF24L01.h>
#include <RF24.h>
RF24 radio(9, 10); // CE, CSN
const byte address[6] = "00001"; //Byte of array representing the address. This is the address where we will send the data. This should be same on the receiving side.
int button_pin = 2;
boolean button_state = 0;
void setup() {
pinMode(button_pin, INPUT);
radio.begin(); //Starting the Wireless communication
radio.openWritingPipe(address); //Setting the address where we will send the data
radio.setPALevel(RF24_PA_MIN); //You can set it as minimum or maximum depending on the distance between the transmitter and receiver.
radio.stopListening(); //This sets the module as transmitter
}
void loop()
{
button_state = digitalRead(button_pin);
if(button_state == HIGH)
{
const char text[] = "Your Button State is HIGH";
radio.write(&text, sizeof(text)); //Sending the message to receiver
}
else
{
const char text[] = "Your Button State is LOW";
radio.write(&text, sizeof(text)); //Sending the message to receiver
}
radio.write(&button_state, sizeof(button_state)); //Sending the message to receiver
delay(1000);
}