Int 21 Fn FF UP - Rational Systems DOS/4gw - Get/set ??? [E]
AH = FFh
DH = 0Ch
DL = ??? (00h or 01h)
Return: CF clear if successful
AL = previous value of ???
CF set on error (DL out of range)
AX = FFFFh
This page created by ng2html v1.05, the Norton guide to HTML conversion utility.
Written by Dave Pearson