Michael Voong HCI Researcher @ Birmingham University

W910i J2ME Bluetooth Stack Problems

I’ve been programming with the W910i recently. Theoretically, it should be a great phone to work with. Plenty of optional APIs included, has a J2ME accessible accelerometer, BUT, Bluetooth keeps failing randomly with the following error message (in console output, testing in Java Developer mode using Sony Ericsson Device Explorer/Connection Proxy):

[Java/OJEX] bt.core[Util.raiseBluetoothConnectionException] FAILED_NOINFO

I’m using a separate thread that keeps making a serial profile connection (BTSPP://) to a GPS device that outputs in NMEA-0183 format. During random times (sometimes 20 secs, sometimes 5 mins) the thread locks up and any attempt to access it locks up that thread too. It must be to do with some of the bugs listed here - even after updating my firmware using the auto update within the device it’s not fixed. There seems to be no fix available anywhere!

I’m going to do a more simpler test later to see if it’s my code, but I doubt it will make any difference.

This is just a warning for those fellow developers out there tearing their hair out. For now, I’m sticking with Nokia phones and my Sparkfun accelerometer… Just need to re-solder that power connection!

That’s an expensive bit of kit. But looks fun to play with. What kinda projects of yours require an accelerometer? I thought you were into the whole “where am I” social business…?

I’m sure you have other hobbies, and I too would be playing with that thing all the time if I had one!

Oh, actually £50 isn’t too bad. I read $ as £!

Even with the newest firmware R1EA030, my W910i often looses connection to bluetooth GPS receiver. This has been seen with 4 different applications. The same receiver and applications worked well on a W810i.

I am experiencing problems with the bluetooth stack. The funny thing is that the problems apperared after performing a SEUS update to latest firwmare.

Now my phone cannot maintain the bluetooth connection with the Hands Free for a normal phone conversation time, it does not even last 2 minutes.

And the thing does not allow you to downgrade to a working versión of the firmware, not even by a SE service point.

If anyone does find a fix, please leave details here…

I have found a solution.

I have downgraded the phone to R1CA039. It seems that the java version of this release (8.0, I think) is more stable as far a the bluetooth stack is concerned than R1EA033 (8.2, I think)