Date: Sun, 18 May 1997 17:59:29 +0300 (IDT)
From: Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
To: "Salvador Eduardo Tropea (SET)" <salvador AT inti DOT edu DOT ar>
cc: djgpp AT delorie DOT com, Owen LaGarde <oml1 AT Ra DOT MsState DOT Edu>
Subject: Re: Funky asm startTimer block -- why the odd 'jmp' statements?
In-Reply-To: <m0wSNlf-000S1kC@natacha.inti.edu.ar>
Message-ID: <Pine.SUN.3.91.970518175708.16797P-100000@is>
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On Fri, 16 May 1997, Salvador Eduardo Tropea (SET) wrote:

> No that's a VERY OLD trick to access devices that aren't enough faster to 
> support 2 consecutive outs at the bus speed. In this case you are accessing to 
> the 8254 integrated in your motherboard so isn't necesary at all. Even more, as 
> DJGPP programms runs on 386 or posterior, you don't need it to access the timer 
> all the 386 motherboards have this chip very well integrated and is faster 
> enough.

A message was posted here a few days ago saying that similar code stopped 
working when the user upgraded to a Pentium.  So it might still be a good 
idea to wait a bit for the timer chip between two I/O instructions.