nRF24l01

[zgxiao]

Hello, Greetings, in the nRF24L01 datasheet, it's mentioned that the module can work as a multiceiver using the six parallel data pepes,my question is that if it is possible for a nRF24l01 module(PRX) to communicate with more than six modules(PTX)?Or can a PRX communicate with multiple PTXs using only one data pipe? thanks

[Janek Mann]

Hi Daniel, you certainly can, assuming that the PRXs are all set to receive on the address that the PTX is transmitting on. However you won't be able to use the built-in acknowledgement feature on more than one PRX (as otherwise the acknowledgement packets would collide). Also you wouldn't be able to use the built-in address matching for more than 6 PTXs so you would need to implement your own address scheme inside of the messages you transmit.

At this point you'd be basically using the NRF24 as a dumb transceiver pipe, more or less.

BTW I would use the NRF51 range for a mesh network today... the radio peripheral in those has many features that make them much better suited, especially due to the very close integration between the radio peripheral and the MCU / Timers (so you can very conveniently schedule the timing of messages / responses / beacons etc). It also allows to for example receive a notification after N bytes of the message have been received, so theoretically it would be possible to set up the appropriate acknowledgement message for the TX node you are receiving from while the message is still being received, allowing for a quicker turn-around time.

[Daniel]

I'm sorry, I don't understand it so much, and I'm also a beginner in arduino and NRF24. Can you explain it for beginners? how the NRF51 can help me to create a real mesh network? Benefits of NRF51 over NRF24L01+ for this purpose, libraries to use or links to any example or tutorial of use about NRF51 please?

[Janek Mann]

Well, to be sure implementing a mesh network on top of the NRF51, from scratch, is not quite a beginners task. You might indeed find it easier in this case to build on somebody else's work in the Arduino ecosystem like this: maniacbug.github.io/.../

You could also have a look at this mesh network implementation hosted by Nordic: github.com/.../nRF51-ble-bcast-mesh (that one has some limitations as it is designed to co-exist with Bluetooth LE, but might be useful as it's already written).

My point regarding the benefits of the NRF51 is perhaps not entirely relevant to a beginner as it would be more important to have existing code to build on.