Hi, Bluetooth on the shimmer will close the connection after it moves out of range, but it takes a minute or two (this is down to the BT spec). You might be able to tweak this timing. Take a look at the RN-42 manual for detais: http://www.rovingnetworks.com/resources/download/47/Advanced_User_Manual. I've just retested with Boilerplate to confirm that this does in fact occur. Also remember that Bluetooth (and most RF comms in general) is not just line-of-sight.
As for 802.15.4, take a look at the TinyOS tutorials. Lesson 3 is probably the most relevant: http://docs.tinyos.net/tinywiki/index.php/Mote-mote_radio_communication Mike On Tue, May 15, 2012 at 8:53 AM, Maxim Michel <[email protected]> wrote: > Hi, > > I tested Bluetooth connection with the Boilerplate firmware. It seems that > when the Shimmer leaves the line-of-sight of the PC, it doesn't close the > BT connection. > Because when it moves back, it just continues streaming again. So > detecting whether the connection has been closed completely isn't the best > way to go I think. > > 802.15.4 seems a bit vague in my opinion. Where can I find the right > information on how to implement this protocol? > > Thanks > > > > 2012/5/15 mike healy <[email protected]> > >> Hi, >> >> An easier way to determine if the Shimmer has lost the BT connection is >> to use Bluetooth.connectionClosed() event. In this event you can just post >> a task to do whatever you want (such as logging to SD). >> >> Equally you can use Bluetooth.connectionMade() event to tell when a BT >> connection is re-established. >> >> You will, however, need to do a bit more work on the host (PC) side to >> (a) realise when the BT connection is lost and (b) re-establish the >> connection when the Shimmer comes back in range (i.e. when the connection >> is lost you will need to periodically scan and when the shimmer is detected >> again establish a new connection). >> >> The 802.15.4 radio is more suitable for the type of scheme you describe >> (as it is connectionless, unreliable, best effort, etc.). >> >> Mike >> >> >> >> On Mon, May 14, 2012 at 7:03 PM, Maxim Michel <[email protected]>wrote: >> >>> Hello again, >>> >>> For my scenario i keep sending a serial command from a c# app to my >>> shimmer every 1 second over Bluetooth. >>> As soon as the Shimmer hasn't got any BT-connection anymore (so no >>> serial commands are received) the Shimmer must perform a function call >>> (i.e. SD-logging() ). When he starts to receive the commands again, it must >>> call another function (i.e. streamingdata() ). >>> >>> Does anyone see a solution on how to write this in code? Or does this >>> seem to be unlikely to work? >>> >>> Thanks >>> >>> >>> _______________________________________________ >>> Shimmer-users mailing list >>> [email protected] >>> https://lists.eecs.harvard.edu/mailman/listinfo/shimmer-users >>> >>> >> >
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