HelpPC 2.10 Quick Reference Utility Copyright 1991 David Jurgens

                   INT 33,D - Mouse Light Pen Emulation On

       AX = 0D

       returns nothing

       - turns on light pen emulation;  the light pen is considered
         down when both buttons are down;   when both buttons are
         up the pen is considered off screen

       - see   INT 33,E

Esc or Alt-X to exit int 33,d Home/PgUp/PgDn/End ←↑↓→
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