Two Peripherals Without Central

[watashi16]

I've got a use case that can essentially be boiled down to two battery-powered devices that have a button and an LED; when the user presses a button on device 1, the LEDs on both devices toggle; the same thing happens when the user presses a button on device 2.

Battery life is important, so I'd like to avoid having one of them act as a central.

I'm struggling trying to find a good approach to this--is there an obvious solution I'm missing? Is there a good resource for determining my power consumption as a central if I need to do that?

[Dmitry]

Agree, bluetooth connection in your case just makes an overhead. Your task requires some response time that you know (as I understand, it's quite short). So, in any case both devices should wake up and listen for peer no less often that this interval. Your power consumption will depend mostly on what's happen every time the device wakes up - for example, in case of BLE connection this would be an exchange with two packets, each of them is at least 80 usec long (at 1 Mbit). That seems not too much, but when devices come out of visibility, central will drain a lot in scanning mode.

The easiest way I see is to listen for a specific packet (containing only access address) on both devices for very short periods with acceptable interval, and transmit a burst of such packets when button is pressed.