Date: Wed, 6 May 1998 13:51:41 +0300 (IDT)
From: Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
To: leger_v AT bluewin DOT ch
cc: djgpp AT delorie DOT com
Subject: Re: timer real and protected mode
In-Reply-To: <354F52DD.60E0@bluewin.ch>
Message-ID: <Pine.SUN.3.91.980506134831.1846J-100000@is>
MIME-Version: 1.0
Content-Type: TEXT/PLAIN; charset=US-ASCII
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On Tue, 5 May 1998 leger_v AT bluewin DOT ch wrote:

> So I removed the real 
> mode handler from the program and it works fine under Dos and Win95.
> My new timer routine run at a rate of 40 tick/sec, and I 
> haven't forgotten to lock the handler and all the variables.
> My question is : does this program works good on other computers than
> mine or should I try to solve the problem with the real mode
> handler(Help's welcome).

You don't need the real-mode handler unless your protected-mode handler 
slows down the system too much.  The DPMI spec ensures that all hardware 
interrupts are always reflected to protected-mode handler first, even 
when the CPU is in real mode.

The DJGPP FAQ list has more details about these issues in section 18.9, 
in case you haven't read it.  If you did read it, and this issue is still 
unclear, please try to suggest how to make it more clear.  I thought I 
had explained this in that section.