NRF24L01 Send Receive problems.

hi, Recently i have bought few of the nrf24l01 module for one of my project, but from the beginning i cannot make it work. i have watched all the tutorial on you tube, and did all the possible things to fix the problem. i am not trying any complicated task to do with it, but only simple send and receive. i am attaching the code i am using, which i got from online tutorials for nrf240l1. i don’t know why it didn’t work with me. i only get this serial output from my receiver side –

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i leave the link for the code here -

please help.

i also want mention that this is not serial baud rate problem, and i noticed one moor thing that the serial output from the receiver keeps coming regardless i turn off the transmitter or not.

This Simple nRF24L01+ Tutorial should get you started.

...R

thanks for the replay, i did exactly the documentation says, but with the code i dont know even if my modules are working. i just put the code in here -

/*

  • 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); // CNS, CE
    const byte address[6] = “00001”;
    void setup() {
    radio.begin();
    radio.openWritingPipe(address);
    radio.setPALevel(RF24_PA_MIN);
    radio.stopListening();
    }
    void loop() {
    const char text = “Hello World”;
    radio.write(&text, sizeof(text));
    delay(1000);
    }

/*

  • 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); // CNS, CE
    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);
    }
    }

sufiansiddiquee:
i just put the code in here -

That does not look like the code from my tutorial. And I am pretty confident that my code works. A number of Forum users have tried it.

It is much easier to help if you use code I am familiar with.

And please post your program using the code button </> so it looks like this. See How to use the Forum

…R

With all respect, i don't know if its your code or not, i just copy and paste. And tried this code as it is. I didn't change anything. And pretty sure my connections was ok. Now I tried example code from Robin2's tutorial post and a part of its working, i am using nano for transmit and uno for receiving and ist working perfectly, but when i do vice versa , it doesn't. Now i have to find out which part not working, is it nano or the nrf24 module? If you have idea., please share. Thanks

sufiansiddiquee:
With all respect, i don't know if its your code or not,

You would know it is my code if you copied it from my tutorial

Now I tried example code from Robin2's tutorial post and a part of its working, i am using nano for transmit and uno for receiving and ist working perfectly, but when i do vice versa , it doesn't. Now i have to find out which part not working, is it nano or the nrf24 module? If you have idea., please share. Thanks

Post the code that YOU have uploaded to your Uno and Nano and I will try to help. Make sure you make NO CHANGES to the code in my examples. When the examples work properly then you can modify the code to do extra stuff.

...R

Do you have a capacitor of 2 to 10 µF directly on the NRF power pins?

If that does not help, try to supply the 3.3V with an extra regulator (had to do that recently on an Uno clone).

Sending seems to draw less peek current so a marginal power supply can lead to the state that you can transmit,
but are unable to receive and - caused by that - unable to acknowledge.