NRF24L and Mega not happy

Projects Networking, Protocols, and Devices
1

Hi, I have five Nano and two Uno running NRF modules using the Example Programs Tx and Rx "Hello World" from the RF24Network library.

I only have one Tx and one Rx testing at a time so no station ID issues.

The following pin outs work perfectly on all Unos and Nanos when in either modes as Tx or Rx. The Mega Tx works OK sometimes and will not Rx at all. Do I have the wrong pins for the Mega or what?

Thanks

1 - GND
2 - VCC 3.3V -- WARNING SHOULD BE 3.3v Not 5V
3 - CE - Uno/Nano pin 9 Mega 9
4 - CSN - Uno/Nano pin 10 Mega 53
5 - SCK - Uno/Nano pin 13 Mega 52
6 - MOSI - Uno/Nano pin 11 Mega 51
7 - MISO - Uno/Nano pin 12 Mega 50

2

The pin numbers look correct although I use 49 for CE. Check wiring again as the last two pins, 54 & 55, on the Mega header are grounded.

// Define nRF24L01+ SPI control pins
#define CE_PIN                  49      // Enable pin
#define CSN_PIN                53      // SS pin


// Set up nRF24L01+ radio on SPI bus
RF24 radio( CE_PIN, CSN_PIN );
3

WaitSome:
The Mega Tx works OK sometimes...

So it is 'or what'.

Pick one or more reasons

  • unstable wiring
  • no extra capacitor on the module
  • 3,3v not powerfull enough (loaded...)
4

Arctic_Eddie:
The pin numbers look correct although I use 49 for CE. Check wiring again as the last two pins, 54 & 55, on the Mega header are grounded.

Thanks, I have checked wiring several times before posting, in fact even used a small NRF24 breakout board so I could swap out NRF modules to rule out the module being faulty. Always only the Mega causing the issue.

I will try the pin 49 approach.