29 Jun
2020
29 Jun
'20
4:37 p.m.
Jonas, I am using an SD card, not CF because I need to move files from a laptop to this
computer using the SD. Having said that, I suspect everything you said is still true. I
don't have access to any linux. But do you think I could make a 300MB partition (for
example) on the SD card and use that? I only have windows 7 or 10 machines available to me
(other than some PDP machines!) I don't need very much space. I would like to run
windows 95 and two or three other programs.
Eugene
-----Original Message-----
From: Jonas M <jm at x25.ee>
Sent: Sunday, June 28, 2020 1:47 AM
To: W2HX <w2hx at w2hx.com>; General Discussion: On-Topic and Off-Topic Posts
<cctalk at classiccmp.org>
Cc: cctech at classiccmp.org
Subject: Re: IDE-SD adapter question
Hi Eugene,
On Fri, Jun 26, 2020 at 09:39:57PM +0000, W2HX via cctalk wrote:
Hi all,
However, I do get errors "sector not found" and if I A)bort I get INT 24 error.
I am trying to get windows 95 installed and this is certainly preventing that.
In the BIOS settings I have the hard drive set as "USER" and these parameters:
CY:[1024] HD:[16] ST:[63] LZ:[1024] WP:[0] These were the parameters
in use while I was still using the actual hard drive.
Question 1: Now that I am using an SD card instead of an IDE drive, what, if anything,
should I be doing with these BIOS parameters?
Question 2: The BIOS has an option to format the hard drive. Should I format the SD card
using this facility?
The sector not found error might be because you formatted the CF in another computer and
created a partition larger than the BIOS supports (which looks like 504 MiB given your CHS
parameters?). It will kind of work and DOS will report the full partition size but once
you start writing over 504 MiB it will wrap around and destroy the data.
From "Enhanced IDE/Fast-ATA/ATA-2 FAQ"
(http://www.faqs.org/faqs/pc-hardware-faq/enhanced-IDE/part1/):
"6.7. I have no fancy EBIOS, but I have an 1GB partition and it works.
Some try to work around the 504MB / 1024 cylinders issue by making a
large partition using a friend's computer, Linux' fdisk, or something
else. They use it for a day or two, conclude that it works, then post
a triumphant article claiming that they found the Solution To
Everyone's Problems[TM].
It will work... for precisely 1024 cylinders. The very moment the OS
or anything else attempts to write something to cylinder 1025 through
int13 calls, the write wraps around to cylinder 0. This cylinder
happens to hold some of the most important data structures on the
disk: the Master Boot Record, partition table, both FAT copies and the
root directory of the first partition."
I had the same thing happen to me the other day with a nice 2 GiB DOS partition installed
on a more modern computer and then moved to a 486.
Started transfering files to it and whoops the whole system gone. :-)
Br,
Jonas