Including channel in advertisement

RE: Including channel in advertisement

Kenneth — Thu, 09 Sep 2021 07:16:13 GMT

[quote user="jeg223"]I would like to keep advertising on the 3 channels, but I would like to include the channel in the payload. I'm guessing the channel is not available to the iPhone app, so it is included in the Manufacturer Data section of the advertisement. [/quote]

Unfortunately it's not possible to update the advertisement dynamically the way you want. The only way would be to include manufacturer data and use one channel, and one channel is not recommended.

[quote user="jeg223"]Also, I noticed in Wireshark that the channels are always in the same order: 37, 38, 39. Will this always be the case? [/quote]

For nordic softdevice controller I expect this to always be the case.

[quote user="jeg223"]Is there a callback I can use to update the payload after each channel is transmitted?[/quote]

Sorry no, the softdevice controller does not allow to update the packet in the middle of a BLE event.

Kenneth

RE: Including channel in advertisement

jeg223 — Wed, 08 Sep 2021 14:06:13 GMT

I would like to keep advertising on the 3 channels, but I would like to include the channel in the payload. I'm guessing the channel is not available to the iPhone app, so it is included in the Manufacturer Data section of the advertisement.

Do you have any suggestion for putting the channel in the payload?

Also, I noticed in Wireshark that the channels are always in the same order: 37, 38, 39. Will this always be the case? Is there a callback I can use to update the payload after each channel is transmitted?

RE: Including channel in advertisement

Kenneth — Wed, 08 Sep 2021 07:25:54 GMT

I recommend to use the recommended advertising intervals, but don't modify the number of advertising channels.

Reason is that if you only advertise on 1 channel you reduce the chance of being discovered, because the scanner will only be able to scan 1 channel at a time. Also have in mind that in BLE there is a 0-10ms random delay for each advertising interval according to BLE specifications, and I assume Apple are aware of that. Their scan window should thereby be broad enough to account for advertising on 3 channels and the random delay.

All that said, here is an example on how to setup 1 channel:
https://devzone.nordicsemi.com/f/nordic-q-a/38695/advertising-and-scanning-on-single-channel/149469#149469