// MasterSwapRoles

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


#define CE_PIN   7
#define CSN_PIN  8

const byte slaveAddress[5] = {'R','x','A','A','A'};
const byte masterAddress[5] = {'T','X','a','a','a'};


RF24 radio(CE_PIN, CSN_PIN); // Create a Radio

char dataToSend[10] = "Message 0";   ----> int dataToSend = 0;
char txNum = '0';             ----> REMOVED
int dataReceived[2];          -----> int dataReceived;
bool newData = false;

unsigned long currentMillis;
unsigned long prevMillis;
unsigned long txIntervalMillis = 1000; // send once per second

//============

void setup() {

    Serial.begin(9600);

    Serial.println("MasterSwapRoles Starting");

    radio.begin();
    radio.setDataRate( RF24_250KBPS );

    radio.openWritingPipe(slaveAddress);
    radio.openReadingPipe(1, masterAddress);

    radio.setRetries(3,5); // delay, count
    send(); // to get things started
    prevMillis = millis(); // set clock
}

//=============

void loop() {
    currentMillis = millis();
    if (currentMillis - prevMillis >= txIntervalMillis) {
        send();
        prevMillis = millis();
    }
    getData();
    showData();
}

//====================

void send() {

        radio.stopListening();
            bool rslt;
            rslt = radio.write( &dataToSend, sizeof(dataToSend) );
        radio.startListening();
        Serial.print("Data Sent ");
        Serial.print(dataToSend);
        if (rslt) {
            Serial.println("  Acknowledge received");
            updateMessage();
        }
        else {
            Serial.println("  Tx failed");
        }
}

//================

void getData() {

    if ( radio.available() ) {
        radio.read( &dataReceived, sizeof(dataReceived) );
        newData = true;
    }
}

//================

void showData() {
    if (newData == true) {
        Serial.print("Data received ");
        Serial.print(dataReceived[0]); ---->  Serial.print(dataReceived)
        Serial.print(", ");            ---->  REMOVED
        Serial.println(dataReceived[1]);  ---->  REMOVED
        Serial.println();       ---->  REMOVED
        newData = false;
    }
}

//================

void updateMessage() {
    txNum += 1;          ---->  REMOVED
    if (txNum > '9') {   ---->  REMOVED
        txNum = '0';     ---->  REMOVED
    }                    ---->  REMOVED
    dataToSend[8] = txNum;    ---->  dataToSend = dataReceived + 1;
}





// SlaveSwapRoles

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


#define CE_PIN   7
#define CSN_PIN  8

const byte slaveAddress[5] = {'R','x','A','A','A'};
const byte masterAddress[5] = {'T','X','a','a','a'};

RF24 radio(CE_PIN, CSN_PIN); // Create a Radio

char dataReceived[10];   ----> int dataReceived;
int replyData[2] = {109, -4000};   ----> int replyData;
bool newData = false;

unsigned long currentMillis;
unsigned long prevMillis;
unsigned long txIntervalMillis = 1000; // send once per second


void setup() {

    Serial.begin(9600);

    Serial.println("SlaveSwapRoles Starting");

    radio.begin();
    radio.setDataRate( RF24_250KBPS );

    radio.openWritingPipe(masterAddress); // NB these are swapped compared to the master
    radio.openReadingPipe(1, slaveAddress);

    radio.setRetries(3,5); // delay, count
    radio.startListening();

}

//====================

void loop() {
    getData();
    showData();
    send();
}

//====================

void send() {
    if (newData == true) {
        radio.stopListening();
            bool rslt;
            rslt = radio.write( &replyData, sizeof(replyData) );
        radio.startListening();

        Serial.print("Reply Sent ");
        Serial.print(replyData[0]);   ---->  Serial.print(replyData);
        Serial.print(", ");   ---->  REMOVED
        Serial.println(replyData[1]);   ---->  REMOVED

        if (rslt) {
            Serial.println("Acknowledge Received");
            updateReplyData();
        }
        else {
            Serial.println("Tx failed");
        }
        Serial.println();
        newData = false;
    }
}

//================

void getData() {

    if ( radio.available() ) {
        radio.read( &dataReceived, sizeof(dataReceived) );
        newData = true;
    }
}

//================

void showData() {
    if (newData == true) {
        Serial.print("Data received ");
        Serial.println(dataReceived);
    }
}

//================

void updateReplyData() {
    replyData[0] -= 1;   ---->  replyData = dataReceived + 10;
    replyData[1] -= 1;    ---->  REMOVED
    if (replyData[0] < 100) {     ---->  REMOVED
        replyData[0] = 109;        ---->  REMOVED
    }                               ---->  REMOVED
    if (replyData[1] < -4009) {      ---->  REMOVED
        replyData[1] = -4000;        ---->  REMOVED
    }                                ---->  REMOVED
}





//My example code

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

RF24 radio(7, 8); // CE, CSN
const byte addresses[][6] = {"00001", "00002"};
float valueTransmit;
float valueRecieved;

void setup() {
  Serial.begin(9600);
  radio.begin();
  radio.openWritingPipe(addresses[1]); // 00002
  radio.openReadingPipe(1, addresses[0]); // 00001
  radio.setPALevel(RF24_PA_LOW);
  valueTransmit = 0
}
void loop() {
  radio.stopListening();
  radio.write(&valueTransmit, sizeof(valueTransmit));
  delay(5);

  radio.startListening();
  if (radio.available() ) {
      radio.read( &valueRecieved, sizeof(valueRecieved) );
  Serial.print(valueRecieved);
  valueTransmit = valueRecieved + 0.01;
  }
}




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

RF24 radio(7, 8); // CE, CSN
const byte addresses[][6] = {"00001", "00002"};
float valueTransmit;
float valueRecieved;

void setup() {
  Serial.begin(9600);
  radio.begin();
  radio.openWritingPipe(addresses[0]); // 00001
  radio.openReadingPipe(1, addresses[1]); // 00002
  radio.setPALevel(RF24_PA_LOW);
}
void loop() {
  radio.startListening();
  if (radio.available() ) {
    radio.read( &valueRecieved, sizeof(valueRecieved) );
    Serial.print(valueRecieved);
    valueTransmit = valueRecieved + 1;
  }

  radio.stopListening();
  radio.write(&valueTransmit, sizeof(valueTransmit));
  delay(5);

}