Category: video
INT 10 - VIDEO - READ LIGHT PEN POSITION (except VGA) AH = 04h Return: AH = light pen trigger flag 00h not down/triggered 01h down/triggered DH,DL = row,column of character light pen is on CH = pixel row (graphics modes 04h-06h) CX = pixel row (graphics modes with >200 rows) BX = pixel column Desc: determine the current position and status of the light pen (if present) Notes: on a CGA, returned column numbers are always multiples of 2 (320- column modes) or 4 (640-column modes) returned row numbers are only accurate to two lines