Date: Mon, 1992 Aug 24   17:16 EDT
From: Bob Babcock   <PEPRBV AT CFAAMP DOT BITNET>
To: djgpp   <djgpp AT sun DOT soe DOT clarkson DOT edu>
Subject: Re: Installable ISRs

>>I want to install a protected mode handler with an entry in go32's
>>idt, to minimise the overhead (in context switching) of handling
>>serial interrupts.
>
>The problem is that you can't guarantee that the interrupt occurs in
>protected mode.  If it occurs in real mode, it bypasses go32
>completely - and you lose it.

Can you have both real and protected mode handlers, and have them talk
to each other so that you preserve the order in which the interrupts
came in?  Perhaps the serial port buffer and associated variables could
be in the first Meg of real memory and shared by the two handlers.