Specifications

Appendix D - CTKERN Function Reference CARROLL TOUCH
D-30 Touch System Programmer’s Guide
If the scaling parameters are set to:
Upper left x = 0
Upper left y = 479
Lower right x = 639
Lower right y = 0
The screen reports 0, 479 when the upper left corner is touched, 639, 0
when the lower right corner is touched, and 0, 0 when the lower left
corner is touched. This places the origin in the lower left corner. By
swapping either or both axes, the origin may be placed in any corner.