Specifications

Appendix C - TAPI Function Reference CARROLL TOUCH
C-16 Touch System Programmer’s Guide
clear the report buffer using Reset (function 0) immediately before
enabling the UEH.
The usual method for using the UEH is for the user program to clear the
report buffer (using Reset (0)), install the handler (using
SetUserEventHandler (7)), read one report per event in the user event
handler, and exit the UEH with an AX = nonzero, causing the report
buffer to be cleared.
Before terminating the user program, be sure to disable the UEH, either
by using SetUserEventHandler (7) or Reset (0). Otherwise, when the
TAPI driver calls the address of where the user program’s event handler
was, it will now be an invalid address.
The SBC driver does not support calling the UEH on non-coordinate
reports. Therefore, the SBC driver ignores bit 1 of BH.