Can nRF51/nRF52 work with 100 or more nRF24L01?

[philipyeung]

I have a wireless project. Requirements as:

• Support platforms: Desktop/Laptop and mobile, Pc/Mac/IOS/Android. etc.

• many connections: flexible but can support 100+ connections

• Response time: ~30ms

• Device Input: 100 or more devices, each with a button, and the platforms will recognize which device button is pressed (may pressed simultaneously)

I have asked similar question before. 
I see nRF24L01 can work with nRF51/nRF52. Can nRF24L01 apply to my project?
That will be 100+ nRF24L01 devices, sending button pressed signal to a nRF51/nRF52 (may simultaneously), and then the nRF51/nRF52 pass the final signal to Platforms.

[Andreas]

Hi,

 

You would probably want to look at the timing descriptions in the nRF24L01+ Product Specification. 100+ devices at a time, with no more than 30ms will not fly, you either need to reduce requirements on either response time or number of connections. Of course if every of the 100+ devices take a long time between each transmission it might be feasible, depending on the time between. If the time between transmissions is reduced, at a point the probability of congestion will increase, and you will likely exceed the response time requirement.

 

Instead of the nRF24L01+ you could use nRF52810s instead. These have shorter radio ramp up time than nRF24L01+. You would then also have more flexibility with regards to the protocol.

 

Best regards,

Andreas

[philipyeung]

Thank you for your answer. And I learned that nRF24L01 need a MCU to custom programming, a max. 6 devices in a Pipe in a Channel. It may not have obvious advantages to use nRF24L01 instead.

[Andreas]

Hi,

 

Correct, the nRF24L01+ is a transceiver IC, it does not have a CPU core. It might therefore be more convenient and not too far off in pricing to run with a nRF52 instead, perhaps unless you are tied to using a different application MCU anyway. Remember nRF52 also has a smaller external BOM, requiring less area.

 

Best regards,

Andreas