nrf24l01 Module not Working with Raspberry Pi Pico W

[Marin-Johnson]

I can use the nrf24l01 wireless module just fine with a Raspberry Pi Pico, but when I try to run the same code on the Raspberry Pi Pico W, it fails to recognize the device. I am using this library, and I get this error:

Traceback (most recent call last):
File "<stdin>", line 31, in <module>
File "nrf24l01.py", line 78, in __init__
OSError: nRF24L01+ Hardware not responding

The boards are supposed to have the same footprint, so what is the difference here? I am using the following pins:

{"spi": 0, "miso": 4, "mosi": 7, "sck": 6, "csn": 14, "ce": 17}

How can I use these modules with the Pico W?

[peterhinch]

Please indicate what pins you are allocating to the device.

[Marin-Johnson]

I am using the following pins:

{"spi": 0, "miso": 4, "mosi": 7, "sck": 6, "csn": 14, "ce": 17}

[peterhinch]

OK, I don't think the problem is the pinout. My guess is that it's because there are two 2.4GHz radio antennas in very close proximity. The NRF's sensitive receiver is next to a relatively powerful transmitter: maybe the NRF doesn't like the WiFi shouting in its ear. This could be proved by turning off the WiFi - I'm not sure how to do this, try the Raspberry Pi docs.

Other ideas are to try a different channel for the NRF.

If I'm right about the cause, a probable solution is this. Sparkfun do a very good NRF24L01 with a reverse SMA connector. A suitable screened cable and a duck antenna would shift the NRF antenna away from the WiFi's.

[Marin-Johnson]

Thank you! Will try these suggestions.

[peterhinch]

Another thought is to turn off access point support: this should quieten the WiFi:

  import network
  sta_if = network.WLAN(network.STA_IF)  # Could deactivate this too?
  ap = network.WLAN(network.AP_IF)  # create access-point interface
  ap.active(False)    # deactivate the interface

[Marin-Johnson]

I just tried this and keep getting the same error: nRF24L01+ Hardware not responding. I also tried adding a delay after turning off the access point in case it took a while to shut down. Thank you for your suggestions.

[Marin-Johnson]

@peterhinch I also tried moving the module farther from the pico, but no change.

[peterhinch]

I've finally found time to try this and I can't replicate the fault. I took the following steps:

1. Set up a Pico with an NRF24L01 on standard pins, copied the driver and nrf24l01test.py to the card.
2. Set up a Pico W with an NRF24L01 on the pins you are using.
3. Copied the driver and nrf24l01test.py to the card.
4. Edited nrf24l01test.py on the card to match your pinout.
5. On the Pico W ran nrf24l01test.responder.
6. On the Pico ran nrf24l01test.initiator. This ran to completion with no errors.

I did nothing with regards to the Pico W's radio. I ran both NRF24L01 boards from 3.3V.

Conclusions:

1. Your pinout is fine.
2. My ideas about the radio are wrong, at least with the radio in its initial state.
3. Something is adrift with your setup. Are you sure your NRF board is still working? I have come across some very dodgy boards from eBay. I use Sparkfun boards which are excellent.

[Marin-Johnson]

What board are you using?

[NMUKHERJEE18]

This one right here: https://www.amazon.com/gp/product/B08LSPZHT8/ref=ppx_yo_dt_b_asin_title_o00?ie=UTF8&psc=1

[Marin-Johnson]

Yeah I never got those work reliability. Try the SparkFun ones here. But yikes they used to be a lot cheaper, until SparkFun discontinued them.

[NMUKHERJEE18]

Will check them out. Thanks

[Rehcerphs]

I ran into this issue after updating the firmware on my Pico. The NRF module was working fine before I updated Pico's firmware. I actually was trying to use between two Pico, and one was flashed with older firmware from 2021 and was working, and the second pico was fresh out the box and I had just flashed with new firmware. This second Pico wasn't working with the NRF module, so I switched it out with an ESP32. Had working communication between the Pico and ESP32 until I flashed new firmware on the first Pico, and now I'm back where I started.