From:	"Michal Strelec" <strelec AT adam DOT osu DOT cz>
Newsgroups:	comp.os.msdos.djgpp
Subject:	RM or PM interrupts
Date:	Mon, 19 Apr 1999 10:44:16 +0200
Organization:	Czech Technical University
Message-ID:	<7feqjh$2is8$1@ns.felk.cvut.cz>
NNTP-Posting-Host:	cl106161.osu.cz
X-Newsreader:	Microsoft Outlook Express 4.72.3110.5
X-MimeOLE:	Produced By Microsoft MimeOLE V4.72.3110.3
Lines:	26
To:	djgpp AT delorie DOT com
DJ-Gateway:	from newsgroup comp.os.msdos.djgpp
Reply-To:	djgpp AT delorie DOT com

Hi,
I've read FAQ(capter 18) and "The Dark Art of writting DJGPP Hardware
interupts", but I have still some questions.

Suppose that my program is in protected mode and suddenly comes interrupt.
Q1: When interrupt apears and proccesor was in PM it stay in PM?
And suppose I've written PM interrupt. So DPMI catch interrupt exception
(still PM?) and gives execution to my PM handler (still PM?). But my program
uses reading and writting to ports (function inportsb,...).
Q2: Are these functions only PM or it has to switch processor to RM?
Q3: Suppose these functions are PM. So my program NEVER switch to RM?

Previous sample was case only interrupts from e.g. communication.

But now comes time interrupt.
Q4: Processor always gets interrupt from timer. And when my program is in PM
and DPMI catch interrupt from timer, it switch to RM and pass to DOS
functions, or it has its own PM alternative?

Huh I think it's all. Sorry my mistakes. I'm using VNC from outside and it's
tooo sloww.

Thanx
Michal.

- Raw text -