Problem using nRF24L01 modules

Using Arduino Programming Questions
1

Hi. I am trying to use two nRF24L01 modules to send data between an arduino uno and an arduino nano (which is the old boatloader version). To start using the modules, I found some code that is supposed to just send a command of "Hello World" from the Uno (transmitter) to the Nano (receiver). However, the Nano prints a bunch of question marks in the serial monitor when I try to use it. What does this mean? I don't think I've wired anything incorrectly, I must have checked the connections 20 times. Is there anything else that may be the problem? Here is the code I am trying to use:

Transmitter (Uno):

/*
* Arduino Wireless Communication Tutorial
*     Example 1 - Transmitter Code
*                
* by Dejan Nedelkovski, www.HowToMechatronics.com
* 
* Library: TMRh20/RF24, https://github.com/tmrh20/RF24/
*/

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

RF24 radio(7, 8); // CE, CSN

const byte address[6] = "00001";

void setup() {
  radio.begin();
  Serial.begin(9600);
  radio.openWritingPipe(address);
  radio.setPALevel(RF24_PA_MIN);
  radio.stopListening();
}

void loop() {
  const char text[] = "Hello World";
  radio.write(&text, sizeof(text));
  delay(1000);
}

Receiver (Nano):

/*
* Arduino Wireless Communication Tutorial
*       Example 1 - Receiver Code
*                
* by Dejan Nedelkovski, www.HowToMechatronics.com
* 
* Library: TMRh20/RF24, https://github.com/tmrh20/RF24/
*/

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

RF24 radio(7, 8); // CE, CSN

const byte address[6] = "00001";

void setup() {
  Serial.begin(9600);
  radio.begin();
  radio.openReadingPipe(0, address);
  radio.setPALevel(RF24_PA_MIN);
  radio.startListening();
}

void loop() {
  if (radio.available()) {
    char text[32] = "";
    radio.read(&text, sizeof(text));
    Serial.println(text);
  }
}

Thanks in advance

2

First off, make sure the serial monitor is set to 9600 baud.

Make sure the nRF24L01s are powered correctly, many problems are because of insufficient current available.

Always show us a good schematic of your proposed circuit.
Show us a good image of your ‘actual’ wiring.
Give links to components.

3

Thanks a lot for the answer. I set the monitor to 9600 baud and the text is being sent fine now. I'll try to always post schematics as well in the future. Sorry I didn't on this post.

4

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