Can one deivice be both the central device and peripheral device?

RE: Can one deivice be both the central device and peripheral device?

Einar Thorsrud — Tue, 05 Aug 2025 13:44:55 GMT

Hi,

What you descrie is possible, but you need to handle relaying of the data i the application layer (for instance receive a notification on one end, and send on another (or write, or similar dependign on how you have designed this).You can see an example of a relay device (your B) in Bluetooth: Central and Peripheral HRS.

RE: Can one deivice be both the central device and peripheral device?

Ziyao Zhou — Tue, 05 Aug 2025 12:27:02 GMT

I have encountered some problems: I have a peripheral node (A), a central/peripheral node (B), and another central node (C). Basically, I want to use B to relay A's data to C, similar to a router. However, there is some control siganl from C to B, I can only receive A's data on B, however, I cannot receive from C.

I am here to confirm whether my design is applicable, if yes, do you have some samples or advice?

Thank you!

RE: Can one deivice be both the central device and peripheral device?

Ziyao Zhou — Thu, 17 Apr 2025 00:24:58 GMT

Thank you so much for your reply!

RE: Can one deivice be both the central device and peripheral device?

Einar Thorsrud — Wed, 16 Apr 2025 07:27:25 GMT

Hi,

Yes. There is only a single radio, and the radio time (and any CPU processing as well) are shared between all the connections. So more connections (in any role), will reduce the potential throughput for each one. For latency it is a bit more complicated, as that depend on the connection parameters, but if you need to increase the connection interval, that will lead to an increase in latency. You can read more about int under Scheduling in the SoftDevice Controller documentation.

RE: Can one deivice be both the central device and peripheral device?

Ziyao Zhou — Wed, 16 Apr 2025 01:35:39 GMT

Hi, some other question would be whether the "relay" will decrese the throughput and increase latency?

RE: Can one deivice be both the central device and peripheral device?

Ziyao Zhou — Mon, 31 Mar 2025 12:37:19 GMT

Thank you for your information!

RE: Can one deivice be both the central device and peripheral device?

Einar Thorsrud — Mon, 31 Mar 2025 12:03:06 GMT

Yes, there is no problem for a device to act as both central and peripheral (and based on that act as for instance a relay). You can see an example of this in the Bluetooth: Central and Peripheral HRS sample.