Android SPP Bluetooth: Implement a Background connection attempt

Question

I would like to minimize the need for user involvement in working with SPP medical devices. The user should only have to pair the device and then connections happen automatically when the device becomes connectable. HDP classic devices are like this and so are BTLE devices (the latter takes work on Android).

So the obvious solution is after pairing, create the RFCOMM Socket and invoke the connect() method (and perhaps all the workarounds to handle the various bugs).

However, this blocking method times out after 12 or so seconds according to the documentation so if I really want to continuously be ready for the device when it 'comes on-line', I need to do this in a while-loop until the connection succeeds.

So the question is if I do this, will this continuous 'pinging' for the device overload the system and drain the battery? Given that something like this happens for HDP implementations on Android, they must also do something like this but maybe they reduce the frequency of pinging so it isn't so resource demanding.

Does anyone have any experience with attempting to do continuous monitoring for SPP devices? Thanks!

Answer 1

I have used Bluetooth SPP connection for industrial devices and had a similar problem. It does not seem a good idea to have a service trying to connect all the time, as it will need to always run on the background and drain more battery.

My solution would be if possible to have the SPP medical device to ask for connection once powered to the paired device(your android), or when you try to connect to the medical device, automate the connection procedure which should take about 1-2 seconds (if you can filter the devices by their MAC address(preferably) or name in your app)

Based on the bluetooth chip in your medical device, you should have plenty of connectivity options from this end, but if not you can try to connect on demand.