Two nrf51 module and a smartphone

[Christian E]

Hi!

I'm am working on a project where there I need to connect two nrf51 modules and a phone. Say: Module A, module B and phone P.

The setup i a bit tricky to explain, but here goes:

Module A shall be a peripheral. It has a sensor connected to it, and it shall notify B and P if certain sensor parameters are breached.

Module B is always present, but A and P might not be present. If B cannot connect to A, then it shall make an alarm(eg. LED, buzzer etc.).

Phone might not be present, but if it is, it shall connect to B and A if A is present. If the phone is present it wants to read sensor data from the two other modules.

I am kind of confused on how to set up roles for the setup. Module be will always be present, so to this sounds like a central. But then how do I connect the central to both phone and A if they are present?

Maybe an alternation of the multilink example? But can a Android phone act as a multilink peripheral?

Any what about 130 dual role?

Any thoughts on this would be much appreciated.

/Christian

[Petter Myhre]

The S130 v2 SoftDevice supports up to 8 connections in total, up to 8 connections as a central, and 1 connection as a peripheral.

Seems like you want A, B and P to be connected to eachother, which means that all of them needs to be in the central and peripheral role concurrently. This is supported by our chipsets, but the peripheral role support for smart phones is pretty fresh, I'm not sure how well it actually works.

Why do they all need to be connected? It is not enough that A is connected to B, and B is connected to P?

[Petter Myhre]

@Christian E Correct. You can have a look at \examples\ble_central_and_peripheral\experimental\ble_app_hrs_rscs_relay in SDK 11. This example on Github may also be useful. You could also consider having another protocol between A and B, for example ANT or gazell, examples found in \examples\multiprotocol. Or ESB.