Hi everybody,
I have a NEC 900c with cmonex 2.0 rom.
Lately I have experienced stylus issue as it looses calibration on low battery power and in the same situation my usb pen isn't recognized.
problems are not present on ac power.
That's a new one on me. From what you wrote, it appears to be a power issue. Did you try and replace the backup battery?
The USB port is understandable as it draws power from the main battery and if you don't have enough available, then the USB device isn't going to be empowered or recognized.
The calibration though is perplexing. I thought those values were stored in the registry after calibration. The only thing that makes sense then is that the power to the lcd unit and the touchscreen is not working either when your power gets too low.
After you notice a loss of calibration, if you do nothing but plug in the a/c adapter, does everything immediately return? If so...then I've just learned something. But I've let my battery run down to nothing, and I've never experienced that symptom before.