Iphone(ios 5.0) Bluetooth Low Energy: can not get data from the device

Question

I got the bluetooth low energy Heart Rate Monitor working using corebluetooth.framework on IOS 5.0. But some times I get the following problems.

1) Sometimes when I start the scan (with scanForPeripheralsWithServices method), It can not discover any BLE(Bluetooth Low Energy) devices until I turn off and turn on the Iphone Bluetooth manually. Occasionaly I had to reboot the phone also if the bluetooth turn off and turn on did not work.

2) Sometimes When I try to connect to the device for which I have stored the UUID previously, I was able to connect to the device, i.e, didConnectPeripheral delegate method was called but It never discovers any services even though I call [peripheral discoverServices:nil] i.e, I am not getting any data from the device in the delegate method didDiscoverServices. For this also I had to reboot the phone.

Answer 1

Try checking the archives here: http://lists.apple.com/archives/bluetooth-dev

and if you don't find it, send the question there. Many Apple Bluetooth engineers answer questions on that mailing list.

Answer 2

1) It has something to do with the pairing routine on bluetooth low energy and the iPhone. The iPhone changes its ID every interval, I don't know how often, but it does. Have you tried just resetting/rebooting the slave device? This often works for me. The slave device also has a limited broadcast period, e.g 20-30 seconds.

2) Again, check that you have reset the slave. I don't know if you have built the device your self or bought a heart rate belt, but this is most often the solution. Oh and by the way, I had an issue where the didDiscoverServices actually jumped over an if-sentence, where I checked for a specific service. This did not fix it self until I rebooted the phone. Really weird behaviour, but I haven't found any other solution to this yet.