Touch screen axes inverted on PXA270

I am using a T20 module with a resistive touch screen and it works fine, however when I change the module to Colibri PXA270 on the same board, the touch screen axes both X and Y are inverted. Top-left corner is bottom-right, top-right is bottom-left.
I tried re calibrating but it didn’t help.
How can I fix this ?

Calibrating the screen should does also define the screen rotation and mirroring. I see two possible reasons why this failed in your case:

  • Did the syste accept the calibration? If you are in a noisy environment, you might need to increase the registry parameter maxCalError. This Microsoft article explains the parameter.
  • Make sure that you save the registry after calibrating the screen, or after changing the maxCalError parameter.

I am using WinCE 6.0 and following the path mentioned in the link, there is no maxCalError parameter in the registry of the device.
Should I create a DWORD with this name and value myself ?

Yes, exactly