BLE question

RE: BLE question

endnode — Tue, 16 Feb 2016 08:34:02 GMT

Hi,

I've done simple BLE repeater and it works without problems (copy 1-to-1 Adv. and Scan Resp. Data) until these two devices have different Adv. Address (MAC as you call it). Sure there are some places where both can be detected so it might confuse some central devices (this is application dependent - e.g. if you simply try to look for the best RSSI it could work). Not sure if it covers your original desire but at least it covers your "main" question. You can even clone the MAC and broadcast 100% matching packets from both devices, but they will never work under connection (Connect Req. packet would target both of them and they would be talking at the same time which would most probably cause noise and link canceling upon some timeout).

It's not very obvious from your original question what you want to achieve in terms of application use case so it's hard to suggest final solution. If you want to just "let the distant central know that there is some broadcaster which middleman sees but maybe not the final listener" then you must move this specific information into Manufacturer Specific data AD object inside Adv. or Scan Resp. Data (as suggested above) or you can transport this information by some custom GATT Service/Characteristic over BLE connection (if it exists between device B and C).

Cheers

RE: BLE question

David Edwin — Mon, 15 Feb 2016 12:50:51 GMT

I think this question has the answers in the comments. I.e. Custom Advertising and Mesh.

You can choose to wrap the advertisement of A within the advertisement of B and then un-wrap it at C. You will need to constrain the length of the advertising data so that it can be wrapped and unwrapped.
You have a mesh, that can do the same for you.

Changing the advertising address so that B, transmits A's packets is possible but not a recommended choice, but it is possible using this example.

RE: BLE question

rushin — Sat, 13 Feb 2016 18:29:39 GMT

can you explain me?? how to relay the original advertising data?

RE: BLE question

awneil — Sat, 13 Feb 2016 13:37:50 GMT

Can't you just put something into the custom data to relay the original advertising data?

Simply duplicating the packet verbatim is going to cause protocol nightmares...

RE: BLE question

rushin — Sat, 13 Feb 2016 13:23:43 GMT

it are BLE devices

RE: BLE question

rushin — Sat, 13 Feb 2016 13:22:33 GMT

here my one ble device advertises. and second ble device advertises first ble device's advertisement packet. can you tell me how to do it??

RE: BLE question

rushin — Sat, 13 Feb 2016 13:20:56 GMT

i know how to put custom data in advertising packet

RE: BLE question

awneil — Sat, 13 Feb 2016 13:13:42 GMT

Look at this post for putting user/custom data in advertising packets:

devzone.nordicsemi.com/.../

Have you looked at BT Mesh networking ... ?

Does it have to be BT, or could you use some other meshing protocol?

RE: BLE question

rushin — Sat, 13 Feb 2016 09:13:19 GMT

so question is can we match advertisement packet ?? or can one BLE device change other device's advertisement packet??