Control output wihout connection

[Inspectron]

Hi,

Is it possible to control the ouputs without connecting?

I mean something like this:

I have a nRF51DK. And I would like to detect if there are bluetooth devices in the area. If yes it should turn on a LED.

I dont want to use an application. It should automaticly detect the device, when it turns on the bluetooth.

And I would like to know if there is something like a unique bluetooth adress? Or is it possible to check the BD_ADDR adress?

So only predifened bluetooth adresses would turn the LED on

[RK]

I don't entirely understand what you're asking.

You can scan for any bluetooth device which is advertising, that's it, there's no other built-in functionality which allows you to find devices which aren't advertising. If a device isn't broadcasting at all (ie it's doing nothing or it's scanning) there's no way to detect it, I suppose technically if a device was in a connection broadcasting packets you could possibly discover it by writing lots and lots and lots of custom radio code which could scan all the available channels and try to find broadcasting devices, but that would be fairly hard.

So you can start a scan and discover advertising devices. That's pretty much it.

I don't either understand "I don't want to use an application". What do you mean by that? You have to write some code to put on the nrf51 at least to do the scanning, that's an application is it not?

As for addresses - there's lots of different types of addresses, some resolvable, some not, some which require a previous bond before they can be resolved. Those are all documented in various BTLE books.

[endnode]

Answers to your two questions in the end are: No (unless you have some specific background application which detests BT start and uses mobile API to start broadcasting - and this must be supported by particular OS API, should be on iOS but not sure about Android and others). In addition: are you mixing classical BT BR/EDR (1.0/2.0/3.0+) and BT Smart aka Bluetooth Low Energy (4.0+)? Because turning Bluetooth interface on mobile usually means enabling BT BR/EDR and BLE (if chip and mobile FW supports it) but you cannot detect with nRF51 any activity done by classical BT (unless you would use chip as raw scanner over 2.4GHz band which might be even impossible HW wise).