I just purchased a set of 10 nRF24l01+ modules with a breakout board that looks like this:

nRF24l01+ module

Note: This is the nRF24l01+ chip, not a clone Si24Ri. Also, I'm using an Arduino Mega.

I'm following the Sparkfun tutorial here:

The wires are hooked up like so:

  • 3.3V → VCC
  • GND → GND
  • PWM 8 → IRQ
  • PWM 9 → CE
  • PWM 10 → CSN
  • PWM 11 → MOSI
  • PWM 12 → MISO
  • PWM 13 → SCK

I've verified the two modules are hooked up as they should be. I'm using the GettingStarted example program for both units. Whenever I go into the serial monitor when connected to the transmitter, I get garbage values like <¯�SžRÖ being output. Whenever I try to transmit a message by entering t, nothing gets returned. The same problem is happening on the receiver end.

As for troubleshooting:

  • I've wiggled all of the jumper cables to verify a stable connection.
  • I've swapped out the modules I was using with others from the package (twice) so the modules probably aren't bad.
  • After reading that a capacitor is sometimes needed to provide a smoother voltage to the module, I upped the voltage from the 3.3V the Arduino was providing to a stable 3.5V from an external variable power supply to account for any small voltage dips. I don't have any capacitors available to me at the moment, so I figured this would be the next best option.

Unfortunately, my RF modules are still not correctly transmitting any data, and I don't know where to go from here.


Check these things first:

  • Is your power supply give a constant 3.3V and a minimum of 0.5A(500mA)?
  • Does your code work for others?
  • Are you on the right serial baud rate?
  • Is the path from the radio to the Arduino as short as possible?
  • Are your MISO and MOSI wires twined into each other?

If none of these things help then, please tell me what library you are using. I had a lot of issues with the RF24 library so maybe try using the NRFLite library.

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