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 covered that in my original answer. You can only detect a device which is transmitting for a start - just having bluetooth 'turned on' means nothing. It could be on and idle, or scanning, if it's not transmitting, there's nothing to detect.

If a device is advertising you can detect it. Doesn't matter WHAT it's advertising (leaving the discussion about directed advertising aside) if it's advertising you can scan for it. But that's a pretty limited case. The last possibility is that it's in connection with another device - theoretically if you wrote lots of code you could find such devices eventually but there's nothing in the BTLE stack to help you.

So basically you can't just detect a device because it happens to have BTLE turned on, you can detect devices with BTLE on advertising something, and the something doesn't matter. Else, you can't.

[RK]

it's possible - that depends on the device, the app, the operating system on the device if any, whether it was connected before it backgrounded, whether the app has been killed and .. I'm sure I could think of more.