Help needed in my code for transmission between 2 nrf24l01+pa+lna

Projects Programming
1

Hello, I need help with my codes. So I'm building a communication system between 2 arduino uno using a nrf24l01+pa+lna on each arduino. For the initial step i have setup 2 system one for transmission and one for recieving. My main goal is for 2 way communication using these 2 systems and using encrypted morse code messages as source of transmission. The setup right now only consists of the nrf directly coneected to arduino uno.
Circuit pin connections of nrf on arduino uno:
GND - GND (digital pwm side)
VCC - 3.3V
CE - PIN D8
CSN - PIN D10
SCK - PIN D13
MOSI - PIN D11
MISO - PIN D12

I need help in understanding what is wrong with my current code and also need help in writing program for inserting a button, lcd with i2c display, led light to the circuit (if any other component necessary also to be added then what should they be). The lcd with i2c will be used for displaying of message, the button for dots and dashes of morse code, led lights for displaying if system is transmitting/recieving (active state) or idle (passive state). The led lights will be of 2 colour red and green for actvie and passive state.

Current code for transmitter:

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

RF24 radio(8, 10); // (CE, CSN)

const byte address[6] = "1RF24"; // address / identifier

void setup() {
  Serial.begin(115200);
  radio.begin();
  radio.openWritingPipe(address); // set the address
  radio.stopListening(); // set as transmitter
}

void loop() {
  const char text[] = "Hi Receiver"; // max. 32 bytes
  radio.write(&text, sizeof(text));
  
  delay(2000);
}

Code for reciever:

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

RF24 radio(8, 10); // (CE, CSN)

const byte address[6] = "1RF24"; // address / identifier

void setup() {
  Serial.begin(115200);
  Serial.println("Start");
  radio.begin();
  radio.openReadingPipe(0,address); // set the address for pipe 0
  radio.startListening(); // set as receiver
}
unsigned long count = 0;
unsigned long last = 0;

void loop() {
  if(radio.available()){
    char text[33] = {0}; 
    radio.read(&text, sizeof(text)-1);
    Serial.println(text);
  }
   count++;
  if (millis()-last> 10000){
    last = millis();
    Serial.println(count);
    count = 0;
  }
}

The part of reciever code that will give me count on serial monitor was suggested by one professional from another forum.
The current issue is the message is not being transmitted.
The result outcome on the reciver seriel monitor:

Screenshot 2025-03-19 200753
Screenshot 2025-03-19 200753183×177 976 Bytes

Please help!

2

You need to allow for a return bool value to actually see if the write was successful or not.

3

I find it a good idea after calling radio.begin(); to call radio.isChipConnected()) to check if the basic SPI connection worked

  Serial.begin(115200);
  delay(2000);
  Serial.println("\n\nNano > NRF24L01 transmit text");
  radio.begin();
  if (radio.isChipConnected())
    Serial.println("Transmitter NF24 connected to SPI");
  else {
    Serial.println("NF24 is NOT connected to SPI");
    while (1)
      ;
  }
4

Another good idea is implement the acknowledgement option on the receiver and transmitter code, so the transmitter can know if the receiver got the message. Makes me wonder how serious you are about using the nRF devices.

5

Well it's my first time working on it but i will try.

Well Thank you for this code. Using this helped me in checking the spi connections of my nrf module.

Sure, will try it.
Since I'm an Communication engineering student I wanted to practical the theory I learn Hence I wanted to do projects on nrf and I'm very much serious about this, I dont care how long it takes but I will do take my steps to "Mission Complete" for my very first project.
Thank You for the help.

6

also have a look at LoRa and LoRaWAN?
most LoRa modules use 3.3V logic therefore if you do use them move to a microcontroller which uses 3.3V logic, e.g. ESP32, Raspberry Pi pico, etc