Resetting a touch screen

[Hugo]

Umm....feeling a bit stupid. I have a Beat N1 head unit in my VW. Purchased in Australia but distributed by Beat Audio in the UK. No doubt a Chinese unit but I'm not sure what specs.

My problem. Recently the calibration of the touch screen was slightly off. I went into "Setup/Screen Calibration" and touched each corner of the screen as requested during the process. I now find out that I was meant to touch a small x just in from each corner. The result, an oversized screen. By that I mean the resolution is fine but the touch locations are all out. I have no control over any application, radio, DVD etc unless I can guess where the button push should be.

"Easy" I hear you say, well the problem is that to get back to "Screen Calibration" on page 3, I need to touch somewhere between my air conditioning controls and the middle of my windscreen!

There appears to be no hard reset on the machine. I have removed it from the dashboard and there is certainly no obvious soft button.
The SD card only appears to read the "MobileNavigator" application as does the USB.

Surely you can't calibrate a unit out of existence......can you?

Any help on how to access the operating system or reset the head unit would be greatly appreciated.

P.S. I believe the machine operates on win CE but thats only a guess from what the dealer (now gone) told me.

[jwoegerbauer]

If device can't be manually re-set to factory defaults, than it's big crap.

And, if it's running on Windows CE 6.0, all it's configuration - means Registry - is stored in files on internal flash drive. You probably will agree that those files can't be repaired/re-written by a hard-reset, which only copies the stock Windows CE 6.0 system files from ROM to internal flash drive.

Hence, use repair service.

[Hugo]

Thanks for your reply.

Yes, you are 100% right. I have had the machine out of the car and into a repair centre and they confirmed what you say. Reloading Windows will not re-write the registry where the touch screen calibration details are stored.

HOWEVER....Luck was on my side. These units are sold in the UK with a remote control (but stupidly not in Australia) I have managed to get my hands on one of these remotes which has allowed me to gain access to the "SETUP/CALIBRATION" screen without using the touch screen.

I have never been so glad to see a blue screen before. I re-calibrated and all is well.

In closing, I find it hard to believe that in 2014, with all the advancements we have made in computing, that someone could create a product/program that could be completely rendered useless with one wrong button push!

Anyway, on this occasion all ended well.

Thanks again for your input and advice.

[Jards88]

Yes well you are talking about an operating system that was released in 2006 and I guess there is no check for whether the inputs on the touch screen are within some limits. I think you can probably blame MS for that as it is most likely a low level O/S function. At least you now know how it works. But then there is the old saying "If you make something idiot proof then someone will just make a bigger idiot" :-)

Cheers, Ian

[jwoegerbauer]

Touchscreen coordinates properly are set by OEM before WinCE unit leaves factory. On a WinCE unit the coordinates are stored in registry under HKLM\Hardware\Touch\CalibrationData and are loaded by touch screen interface (GWES) at boot time.

Wondering why people try to utilize the native WinCE touch interface (GWES), this because WinCE 6.0 launches "touchc.exe"/"touchcali.exe"/"touchscreen.exe"/etc.pp everytime automatically if it detects invalid touchscreen coordinates in registry. At least this I noticed beeing the case with most WinCE 6.0 units I had in my hands.

And, each WinCE device's withcoming "touchscreen calibrator" always tells user how to do -> point with stylus exactly to the 4 edge-signs shown.