How to send 500bytes+ every 20ms using Bluetooth 5 advertising extensions (and possibly mesh)

[Fred Rfn]

Hi, 

I am working on NRF52 series (NRF52 DK and NRF52832) and would like to know whether it is possible to use Bluetooth 5 extended advertising capabilities to send, let's say, 500 bytes of data at once, every 20ms (said data is modified at roughly the same frequence).

Theoretically, combining extended payload and chaining (up to 7 packets according to the Bluetooth 5 spec), it should be possible.

How to do that with the NRF5 SDK? A sample, or at least guidelines would really be appreciated.

Bonus question:

Is it possible to transfer the same amount of data at once with NRF5 SDK for Mesh, using for instance the Instaburst module? I don't really understand the sentence saying the theoretical upper throughput would be 160kbps, yet it says that we can't reach more than 60kbps in practice due to mesh packets overhead.

https://infocenter.nordicsemi.com/index.jsp?topic=%2Fcom.nordic.infocenter.meshsdk.v5.0.0%2Fmd_doc_user_guide_modules_instaburst.html&cp=7_2_2_4_4

If possible - maybe a few pointers about what config must me adjusted and relevant code snippets (such as for the custom mesh model to send string messages) to use Instaburst would be welcome. 

Thanks in advance

[Marjeris Romero]

Hi,

S132 has support for advertising and scanning up to 255 bytes of advertising data in advertising event when using Extended Advertising support: https://infocenter.nordicsemi.com/topic/sds_s132/SDS/s1xx/s130.html

For the question about Mesh: Mesh uses normal advertising packets by Mesh specification (28 bytes packets + 3 bytes for header on air, but 11 byte actual payload). Instaburst provides higher throughtput using extended advertising and the expense of breaking spec compliance.

We currently don't have an example with Instaburst however you can follow the steps in this Devzone ticket to enable this feature: https://devzone.nordicsemi.com/f/nordic-q-a/70768/example-project-for-mesh-instaburst/299092#299092

Best regards,

Marjeris