Date: Sun, 8 Mar 1998 16:32:57 +0200 (IST)
From: Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
To: Serge Pachkovsky <ps AT ocisgi7 DOT unizh DOT ch>
cc: djgpp AT delorie DOT com
Subject: Re: _bios_disk() inefficiency
In-Reply-To: <35029541.0@rzunews1.unizh.ch>
Message-ID: <Pine.SUN.3.91.980308162836.23333A-100000@is>
MIME-Version: 1.0
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On 8 Mar 1998, Serge Pachkovsky wrote:

> No Eli, you can't - most floppy disk BIOSes do not support reading more
> that one cylinder's worth of data in a single call.

The original message didn't tell how much did the program read in one 
call.  For all I know, they could read a sector, not a cylinder.

> BIOS can do it (something you shouldn't rely upon), 8-bit DMA channel
> used by floppy drives won't allow you to transfer more than 64Kb worth
> of data without re-initialization.

Even so, reading several 64b-long buffers one after the other will be 
faster with floppies, since you don't need to wait till the motor spins 
up.

Anyway, all of this is academic, since the original message didn't even 
tell that a floppy was being read (as opposed to a hard disk).