Re: Paused I/O versus regular I/O

From: Bodo Eggert
Date: Sat Nov 26 2005 - 20:24:46 EST


Jean Delvare <khali@xxxxxxxxxxxx> wrote:

> Could anyone tell me what the difference is between "paused" I/O
> (inb_p, oub_p and friends) and regular I/O (inb, oub and friends)? I
> understand that the former includes some delays here and there, but how
> do I know when to use the paused variant, and when the non-paused
> variant is OK?

AFAIK, some old hardware needs it. The original ISA bus speed was 4.77 MHz,
and AT changed it to 8 MHz. Some chips needed extra delays to compensate,
and those chips stayed around for a long time.

--
Ich danke GMX dafür, die Verwendung meiner Adressen mittels per SPF
verbreiteten Lügen zu sabotieren.
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