OT 3.5" floppy question

Robert Roland wrote:

Newer harddisks use voice coils to position the heads. Unlike the
stepper, the voice coil cannot be moved to a specific position without
feedback from servo tracks embedded in the disk platters. If you
degauss a voice coil drive, it becomes completely useless.

I know I'm nitpicking, but I can't help myself. :-)

Because a drive uses voicecoil technology to position the heads, does
not necessarily mean it MUST use pre-recorded tracks on the magnetic
surface.

I've seen at least one drive that used a shuttered disk, and optics to
count positions from "park", all the way to the other end.
Technically, it would be plausible for the manufacturer to encode LLF
routines into the drive, but that said, I've never seen it.

But true, most if not all drives now exclusively use pre-recorded tracks
to synchronise the head positions, and a degauss would render that
slightly stuffed.

snip
Anyway, thanks for the kick and the information. I'll see if
I can refresh my sad memory.

Hi guys, If you want to direct me to a different group that is fine.
I'm wondering if there is a way to format a HD 3.5" floppy to be only
DD? (HD is high desinity 1.44MB and DD is double density ~720kB, for
those of tender years.) I've been mucking about in DOS trying the
"format a: /F:(size)" command with out success. I also tried putting
some tape on the one corner of the disk to cover up the hole there.

Thanks for any advice,

George H.

On Sat, 24 Sep 2011 12:36:51 +1000, David Eather
eather_at_tpg.com.au> wrote:

On 21/09/2011 1:56 AM, David Eather wrote:
On 21/09/2011 12:06 AM, George Herold wrote:
Hi guys, If you want to direct me to a different group that is fine.
I'm wondering if there is a way to format a HD 3.5" floppy to be only
DD? (HD is high desinity 1.44MB and DD is double density ~720kB, for
those of tender years.) I've been mucking about in DOS trying the
"format a: /F:(size)" command with out success. I also tried putting
some tape on the one corner of the disk to cover up the hole there.

Thanks for any advice,

George H.

Cover the extra hole on the HD floppy disk. All HD floppy DD I have seem
also support DD when feed the appropriate media

Just remembered something that will help. For what your after (format a
DD on HD drive) it helps to bulk erase the disk first (helps with both
HD and DD disks) to remove all that pre-formatted stuff that will just
become noise after formatting.

I vaguely recall that most floppy drive controllers in the
commodity marketplace cannot actually format blank media --
by this, I mean raw magnetic material.

On 24/09/2011 1:01 PM, Jon Kirwan wrote:
On Sat, 24 Sep 2011 12:36:51 +1000, David Eather
eather_at_tpg.com.au> wrote:

On 21/09/2011 1:56 AM, David Eather wrote:
On 21/09/2011 12:06 AM, George Herold wrote:
Hi guys, If you want to direct me to a different group that is fine.
I'm wondering if there is a way to format a HD 3.5" floppy to be only
DD? (HD is high desinity 1.44MB and DD is double density ~720kB, for
those of tender years.) I've been mucking about in DOS trying the
"format a: /F:(size)" command with out success. I also tried putting
some tape on the one corner of the disk to cover up the hole there.

Thanks for any advice,

George H.

Cover the extra hole on the HD floppy disk. All HD floppy DD I have seem
also support DD when feed the appropriate media

Just remembered something that will help. For what your after (format a
DD on HD drive) it helps to bulk erase the disk first (helps with both
HD and DD disks) to remove all that pre-formatted stuff that will just
become noise after formatting.

I vaguely recall that most floppy drive controllers in the
commodity marketplace cannot actually format blank media --
by this, I mean raw magnetic material.

Unless that happened (for some reason) after 1995 it most defiantly is
not true. But as other mention the HDD change to voice coil did cause
that problem for them.

On Mon, 26 Sep 2011 00:44:08 +1000, David Eather
eather_at_tpg.com.au> wrote:

On 24/09/2011 1:01 PM, Jon Kirwan wrote:
On Sat, 24 Sep 2011 12:36:51 +1000, David Eather
eather_at_tpg.com.au> wrote:

On 21/09/2011 1:56 AM, David Eather wrote:
On 21/09/2011 12:06 AM, George Herold wrote:
Hi guys, If you want to direct me to a different group that is fine.
I'm wondering if there is a way to format a HD 3.5" floppy to be only
DD? (HD is high desinity 1.44MB and DD is double density ~720kB, for
those of tender years.) I've been mucking about in DOS trying the
"format a: /F:(size)" command with out success. I also tried putting
some tape on the one corner of the disk to cover up the hole there.

Thanks for any advice,

George H.

Cover the extra hole on the HD floppy disk. All HD floppy DD I have seem
also support DD when feed the appropriate media

Just remembered something that will help. For what your after (format a
DD on HD drive) it helps to bulk erase the disk first (helps with both
HD and DD disks) to remove all that pre-formatted stuff that will just
become noise after formatting.

I vaguely recall that most floppy drive controllers in the
commodity marketplace cannot actually format blank media --
by this, I mean raw magnetic material.

Unless that happened (for some reason) after 1995 it most defiantly is
not true. But as other mention the HDD change to voice coil did cause
that problem for them.

Yeah, I may be confusing things. There were times when I
couldn't low level format floppies using Microsoft's DOS
commands to do it. But could, after completely restoring
them using Central Point's software/hardware solution. Since
I'm not a guru on these things (and was wise enough to open
the door to the idea that I didn't know for sure what I was
saying), I'll allow that there was some other reasonable
explanation for my experiences than I imagined.

Jon

On Sat, 24 Sep 2011 01:21:37 -0700, I wrote:

snip
Anyway, thanks for the kick and the information. I'll see if
I can refresh my sad memory.

Well, "Central Point" is what made it, I think. Vague memory
came back, maybe. Gives me a starting point. I think it was
called an Enhanced or Deluxe Option board or something like
that.

Might be easier to find the docs, now that I have a clue what
I'm looking for.

On Mon, 26 Sep 2011 00:44:08 +1000, David Eather
eather_at_tpg.com.au> wrote:


Unless that happened (for some reason) after 1995 it most defiantly is
not true. But as other mention the HDD change to voice coil did cause
that problem for them.

On 2011-09-25, Jon Kirwan <jonk_at_infinitefactors.org> wrote:
On Mon, 26 Sep 2011 00:44:08 +1000, David Eather
eather_at_tpg.com.au> wrote:


Unless that happened (for some reason) after 1995 it most defiantly is
not true. But as other mention the HDD change to voice coil did cause
that problem for them.

ms-doe 5(?) had a feature where a corrupted boot sector could stop format
from working. ther ewas some command-line override IIRC.

In article <lr9s77h9v2cjr60ut4u0ddmprodhlojvbm_at_4ax.com>,
Jon Kirwan <jonk_at_infinitefactors.org> wrote:
On Sat, 24 Sep 2011 01:21:37 -0700, I wrote:

snip
Anyway, thanks for the kick and the information. I'll see if
I can refresh my sad memory.

Well, "Central Point" is what made it, I think. Vague memory
came back, maybe. Gives me a starting point. I think it was
called an Enhanced or Deluxe Option board or something like
that.

Might be easier to find the docs, now that I have a clue what
I'm looking for.

I think that's might be one of those special cards that could
read Macintosh (and Commodore?) disks. There were at least two
different companies that made them.

On 26/09/2011 2:23 AM, Jon Kirwan wrote:
On Mon, 26 Sep 2011 00:44:08 +1000, David Eather
eather_at_tpg.com.au> wrote:

On 24/09/2011 1:01 PM, Jon Kirwan wrote:
On Sat, 24 Sep 2011 12:36:51 +1000, David Eather
eather_at_tpg.com.au> wrote:

On 21/09/2011 1:56 AM, David Eather wrote:
On 21/09/2011 12:06 AM, George Herold wrote:
Hi guys, If you want to direct me to a different group that is fine.
I'm wondering if there is a way to format a HD 3.5" floppy to be
only
DD? (HD is high desinity 1.44MB and DD is double density ~720kB, for
those of tender years.) I've been mucking about in DOS trying the
"format a: /F:(size)" command with out success. I also tried putting
some tape on the one corner of the disk to cover up the hole there.

Thanks for any advice,

George H.

Cover the extra hole on the HD floppy disk. All HD floppy DD I
have seem
also support DD when feed the appropriate media

Just remembered something that will help. For what your after
(format a
DD on HD drive) it helps to bulk erase the disk first (helps with both
HD and DD disks) to remove all that pre-formatted stuff that will just
become noise after formatting.

I vaguely recall that most floppy drive controllers in the
commodity marketplace cannot actually format blank media --
by this, I mean raw magnetic material.

Unless that happened (for some reason) after 1995 it most defiantly is
not true. But as other mention the HDD change to voice coil did cause
that problem for them.

Yeah, I may be confusing things. There were times when I
couldn't low level format floppies using Microsoft's DOS
commands to do it. But could, after completely restoring
them using Central Point's software/hardware solution. Since
I'm not a guru on these things (and was wise enough to open
the door to the idea that I didn't know for sure what I was
saying), I'll allow that there was some other reasonable
explanation for my experiences than I imagined.

Jon

Is it possible that this is a format / quick format thing? There is no
genuine high/low level format on a FDD (at least up to 1995) but they
did introduce a quick format (same command just different switches or it
may have even been been the default on dos 5 ?) - It really only reset
some directory and FAT information. If a FD was bulk erased a quick
format would fail pretty much in the way you describe. I have a FDD - if
it still works and I can find a FD I'll give it a try - info in a few days

On Mon, 26 Sep 2011 18:38:24 GMT, mzenier_at_eskimo.com (Mark
Zenier) wrote:

In article <lr9s77h9v2cjr60ut4u0ddmprodhlojvbm_at_4ax.com>,
Jon Kirwan <jonk_at_infinitefactors.org> wrote:
On Sat, 24 Sep 2011 01:21:37 -0700, I wrote:

snip
Anyway, thanks for the kick and the information. I'll see if
I can refresh my sad memory.

Well, "Central Point" is what made it, I think. Vague memory
came back, maybe. Gives me a starting point. I think it was
called an Enhanced or Deluxe Option board or something like
that.

Might be easier to find the docs, now that I have a clue what
I'm looking for.

I think that's might be one of those special cards that could
read Macintosh (and Commodore?) disks. There were at least two
different companies that made them.

I may not remember much accurately about the board, right
now, but I do know I didn't buy it for that purpose.

In article <n8j587lo87d9pt9tdbnda03gsvabgma99p_at_4ax.com>,
Jon Kirwan <jonk_at_infinitefactors.org> wrote:
On Mon, 26 Sep 2011 18:38:24 GMT, mzenier_at_eskimo.com (Mark
Zenier) wrote:

In article <lr9s77h9v2cjr60ut4u0ddmprodhlojvbm_at_4ax.com>,
Jon Kirwan <jonk_at_infinitefactors.org> wrote:
On Sat, 24 Sep 2011 01:21:37 -0700, I wrote:

snip
Anyway, thanks for the kick and the information. I'll see if
I can refresh my sad memory.

Well, "Central Point" is what made it, I think. Vague memory
came back, maybe. Gives me a starting point. I think it was
called an Enhanced or Deluxe Option board or something like
that.

Might be easier to find the docs, now that I have a clue what
I'm looking for.

I think that's might be one of those special cards that could
read Macintosh (and Commodore?) disks. There were at least two
different companies that made them.

I may not remember much accurately about the board, right
now, but I do know I didn't buy it for that purpose.


A vague memory surfaces: a controller for a (automatic feed?)
diskette duplicator capable of making copy protected disks.

Google seems to confirm.

On 27 Sep 2011 11:10:28 GMT, Jasen Betts <jasen_at_xnet.co.nz
wrote:

On 2011-09-25, Jon Kirwan <jonk_at_infinitefactors.org> wrote:
On Mon, 26 Sep 2011 00:44:08 +1000, David Eather
eather_at_tpg.com.au> wrote:


Unless that happened (for some reason) after 1995 it most defiantly is
not true. But as other mention the HDD change to voice coil did cause
that problem for them.

ms-doe 5(?) had a feature where a corrupted boot sector could stop format
from working. ther ewas some command-line override IIRC.

That wasn't my problem. There was a switch option for that
on hard disks, at least. I had used it, on occasion. But
hard disks supported partitioning. I don't recall floppies
being partitioned.

My daughter has a multi head commercial Embroidary machine where the
only conection to the computer prog to drive it is via 720kb diskettes.
She swears as soon as she can afford a new machine it will at least be
ethernet or maybe wifi.