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kishy
September 12th, 2009, 05:23 PM
I have gone through the last couple days extensive testing (basically, Scandisk and a format with two different drives on the same set of disks) on the majority of my 5.25" floppy disks. All disks are DS/DD except a couple which are those oddball 96tpi disks (I don't even know what you call those). All were and are formatted as 1.2mb.

The reason for the testing was the high rate of errors I was finding the last time I used them. "Data error reading drive B", "General failure reading drive B", "Seek error reading drive B" and the like.

The results are not surprising, and not good. All of them are at least 50% bad sectored, giving me (in effect) a pile of unreliable 360k disks...

I sort of doubt it, but is there any sort of magic repair solution for these? Perhaps some kind of waving pattern with a magnet?

Once bad sectors start developing, my understanding (and experience) is that the affected disk will just keep getting worse with time, whether it is used or not, so they're basically trash from the time the first bad sector develops.

Any ideas? If it's a hopeless cause I'll turn them into some kind of decoration.

Oh, and I have a never-opened box of Fujifilm 5.25" disks with a lifetime replacement warranty based on manufacturer defects. Given that the package has never been opened, wouldn't anything wrong with them technically be a manufacturer defect? I wonder if Fujifilm is prepared to back up that warranty...

mbbrutman
September 12th, 2009, 05:48 PM
Clean the heads on your floppy drives. A lot of errors are transient and are caused by dirty drive heads. Clean and lubricate the rails on the drive as well. Poor track positioning can lead to read errors. Finally, if it is data you need to recover try another drive. Slight differences in head alignment can make a difference.

If this is just a matter of deciding whether to throw a diskette away or not, a bulk eraser might help. If the diskette has developed a physical error it will probably never be curable though.

Chuck(G)
September 12th, 2009, 06:11 PM
If the diskette was written 20 years ago with no errors on anything less than floor sweepings, it's probably readable with no or very few errors today. After thousands of diskettes, that's my experience.

First off, clean the drive heads. When you're resurrecting old floppies, this needs to be done frequently, as old media does shed and gunk up the heads.

One thing that we see is diskettes written on drives with alignment problems. If they were formatted and written on misaligned drives, they'll have to be read with misaligned drives.

If you have an oscilloscope, also check the bitrate of the recorded data and adjust your reading drive spindle speed accordingly, if need be.

Floppies, particularly DSDD 5.25" and 8" are extremely reliable if the coating manages to stay stuck to the cookie substrate.

Finally, if your 360K floppies were written on a 1.2M drive, you'll need to read them on a 1.2M drive--or at least a 96 tpi drive.

720K and 1.44M floppies use much thinner coatings and recovery is much less a certain proposition.

kishy
September 12th, 2009, 07:34 PM
Clean the heads on your floppy drives. A lot of errors are transient and are caused by dirty drive heads. Clean and lubricate the rails on the drive as well. Poor track positioning can lead to read errors. Finally, if it is data you need to recover try another drive. Slight differences in head alignment can make a difference.

If this is just a matter of deciding whether to throw a diskette away or not, a bulk eraser might help. If the diskette has developed a physical error it will probably never be curable though.

I use multiple drives to try to reduce the chance of that being an issue (I said 2 in the original post, but it's actually 6, though I do recognize the issue of head misalignment - fortunately all drives are able to read each others disks). These are disks which, prior to me getting them, were stored extremely poorly.

I'd, of course, still like to clean the heads on the drives.


If the diskette was written 20 years ago with no errors on anything less than floor sweepings, it's probably readable with no or very few errors today. After thousands of diskettes, that's my experience.

First off, clean the drive heads. When you're resurrecting old floppies, this needs to be done frequently, as old media does shed and gunk up the heads.

One thing that we see is diskettes written on drives with alignment problems. If they were formatted and written on misaligned drives, they'll have to be read with misaligned drives.

If you have an oscilloscope, also check the bitrate of the recorded data and adjust your reading drive spindle speed accordingly, if need be.

Floppies, particularly DSDD 5.25" and 8" are extremely reliable if the coating manages to stay stuck to the cookie substrate.

Finally, if your 360K floppies were written on a 1.2M drive, you'll need to read them on a 1.2M drive--or at least a 96 tpi drive.

720K and 1.44M floppies use much thinner coatings and recovery is much less a certain proposition.

The disks in question were all sold blank and then written by the end user, and have all been stored poorly (all of the misperforming ones that is - I have some pristine ones that were, accordingly, stored perfectly).

The disks are not 360k - they are 1.2's which have about 360k usable space on account of the bad sectors (physical damage, correct?).

Because the disks have bad sectors (which are marked as bad sectors), does this rule out the dirty drive issue? Even if I clean the drive heads it will make no differences, the sectors are still marked bad. Is there, by chance, a way to un-mark the bad sectors and then rescan the disks with the newly cleaned drive? (thought process at work here: if a dirty drive thought the sector was damaged because of the drive heads being dirty, not the disk being bad, then it would mark a GOOD sector as being bad anyway)

Can anyone recommend a decent guide for drive cleaning? Or alternatively tell me if the procedure I already know is correct or not: qtip, isopropyl alcohol, dabbing motion on heads (NOT rubbing action).

edit: pics show a couple of the EXTREME cases (the last one is actually a 360k, but it's one of only one or two in the lot)

http://img44.imageshack.us/img44/6484/badsectors1.jpg
http://img121.imageshack.us/img121/3460/badsectors2.jpg
http://img121.imageshack.us/img121/5070/badsectors3.jpg

dave_m
September 12th, 2009, 09:21 PM
All disks are DS/DD except a couple which are those oddball 96tpi disks (I don't even know what you call those). All were and are formatted as 1.2mb.



I am confused. If the floppies are only double density, why are you formating them to 1.2MB (high density)?

Chuck(G)
September 12th, 2009, 10:56 PM
I am confused. If the floppies are only double density, why are you formating them to 1.2MB (high density)?

That had me scratching my head. Trying to fromat DSDD to DSHD will produce exactly these results. The coating on a DSHD has completely different characteristics (coercivity, thickness, particle size, loading, etc.).

kishy
September 13th, 2009, 07:55 AM
I am confused. If the floppies are only double density, why are you formating them to 1.2MB (high density)?

I didn't format them to 1.2; they came to me already as 1.2 (so naturally if I run format without any switches it will format to 1.2 again). As far as I was aware there was no such thing as a high density 5.25" floppy and that DD was in fact 1.2MB. Obviously my understanding was flawed (but let's keep in mind this stuff was already going out the window around the time I was born).


That had me scratching my head. Trying to fromat DSDD to DSHD will produce exactly these results. The coating on a DSHD has completely different characteristics (coercivity, thickness, particle size, loading, etc.).

That does make tons of sense (now knowing my flawed understanding); I did however not know that DSHD even existed to begin with (in the case of 5.25's)

My comment about "oddball" 96tpi disks is because they are a minority in the disks I have and are marked as being 1.6MB, which my drives can't format (or at least the format command can't format).

per
September 13th, 2009, 08:37 AM
My comment about "oddball" 96tpi disks is because they are a minority in the disks I have and are marked as being 1.6MB, which my drives can't format (or at least the format command can't format).

Those 96tpi disks are the only ones that actually can be properly formated as 1.2MB disks. The rest are problably 48tpi (Double Density = 360Kb).

kishy
September 13th, 2009, 09:02 AM
Those 96tpi disks are the only ones that actually can be properly formated as 1.2MB disks. The rest are problably 48tpi (Double Density = 360Kb).

Aw crap, so I've (or more likely the previous disk owners) basically destroyed a bunch of 360k disks?
Live and learn I guess...

What process, if any, could I go through to get these back to a usable state?
For example, unmark "bad sectors" (which probably aren't bad at all, since they don't exist) then format with the /4 switch (360k)?

Edit:
format b: /4 /c
then scandisk it, there's nothing wrong with the disks

Someone slap me, please?

mbbrutman
September 13th, 2009, 09:30 AM
Bulk erase, then format with the correct format for the density of the disk ...

kishy
September 13th, 2009, 09:35 AM
Bulk erase, then format with the correct format for the density of the disk ...

My apologies, my edit must have been too late before your reply.

One point though...if DSHD is 1.2 and DSDD is 360k, but 96TPI is 1.2...

I have DSDD disks with 96TPI, what should these properly be formatted as?

Chuck(G)
September 13th, 2009, 10:03 AM
Like I said, 5.25" (360K) diskettes are very reliable--not as reliable as 8" in my experience, but the differential is mostly due to bargain brand diskettes with lousy coatings (e.g. Wabash).

I wish I could say the same about most 3.5" DSHD media.

mbbrutman
September 13th, 2009, 10:25 AM
We've got two different parameters to worry about.

The magnetic coercivity (http://en.wikipedia.org/wiki/Coercivity) of a material determines what kind of 'force' is required to leave an imprint on the material. High density diskettes use a different materials. There is a good table here: http://en.wikipedia.org/wiki/Floppy_disk_format .

The other parameter is the tracks per inch. The tracks per inch is a function of the drive and the head size on the drive, not the media. (Up to a certain point that is, but lets go crazy.) The good old double density 5.25 inch drive capable of 360KB per drive only writes 40 tracks per side because the drive heads are so damn big! With a smaller drive head, you could write more tracks per side. Consider the high density 5.25 inch drive - it has a narrower head capable of writing 80 tracks per side.

Under software control you can use a 1.2MB drive to write 80 tracks per side to double density media. That effectively doubles the capacity of a 360KB (double density) diskette, not through magic but by just simply using a narrower drive head. This wasn't a standard format, so it's not going to be readable unless you use the same software to read it back. (Fdformat did this.) These diskettes will also be unreadable in a standard double density (40 track) drive.


Mike

Chuck(G)
September 13th, 2009, 10:48 AM
The magnetic coercivity (http://en.wikipedia.org/wiki/Coercivity) of a material determines what kind of 'force' is required to leave an imprint on the material. High density diskettes use a different materials. There is a good table here: http://en.wikipedia.org/wiki/Floppy_disk_format .


It's far more complicated than that, Mike. Not only the coercivity of the material (e.g. Iron oxide vs. Barium ferrite), but the thickness of the coating (at higher data rates, a too-thick coating increases bit-shift issues), the particle size (must be small enough to support smaller bit cells) and the "loading" or the ratio of magnetic material to binder (high density diskette generally have much lower loading, which is one reason that their coatings appear to be almost transparent).

A new degaussed 5.25" HD floppy can sometimes be used in a pinch as DD media. When I get one mixed into a batch of DD media for conversion, I get sweaty palms, but most often, they do seem to work, even after 20 years of sitting around.

As far as "standard" formats go, the PC 720K 3.5" format will work fine on a 1.2MB drive using DD diskettes, provided that you have a driver to overcome the stupidity of the BIOS. Lots of vendors made 80 cylinder DD (sometimes called QD) drives and you could buy diskettes that were verified for QD use. There were a few "clone" BIOSes that could handle 720K 5.25" in a 1.2M drive without any special software.

All in all, I admire NEC's 9800 series of PCs. They started with 8" and moved to 5.25" and then to 3.5"--with all having exactly the same logical format--all spin at 360 RPM and use the same data rate.

kishy
September 13th, 2009, 10:50 AM
Like I said, 5.25" (360K) diskettes are very reliable--not as reliable as 8" in my experience, but the differential is mostly due to bargain brand diskettes with lousy coatings (e.g. Wabash).

I wish I could say the same about most 3.5" DSHD media.

I am kind of surprised by this reliability - the fact that these disks were stored in quite poor conditions for years, then sat by me next to unshielded speakers for years (before I knew any better!), formatted to an incorrect format and then formatted back (and used in tons of drives) definitely does attest to the 'build quality'.

So it's not my imagination that 3.5" 1.44 disks seem to have a high failure rate...at least the ones I use all the time. Fortunately I have tons of them and people throw them at me by the bucketful, so even if I only get one last use out of a disk (be it for a bootdisk or moving a DOS game somewhere or whatever) it's not a total disaster. All of my actual data STORAGE is done on external hard drives and optical disks, I only use floppies for transporting stuff between floppy-only computers.


We've got two different parameters to worry about.

The magnetic coercivity (http://en.wikipedia.org/wiki/Coercivity) of a material determines what kind of 'force' is required to leave an imprint on the material. High density diskettes use a different materials. There is a good table here: http://en.wikipedia.org/wiki/Floppy_disk_format .

The other parameter is the tracks per inch. The tracks per inch is a function of the drive and the head size on the drive, not the media. (Up to a certain point that is, but lets go crazy.) The good old double density 5.25 inch drive capable of 360KB per drive only writes 40 tracks per side because the drive heads are so damn big! With a smaller drive head, you could write more tracks per side. Consider the high density 5.25 inch drive - it has a narrower head capable of writing 80 tracks per side.

Under software control you can use a 1.2MB drive to write 80 tracks per side to double density media. That effectively doubles the capacity of a 360KB (double density) diskette, not through magic but by just simply using a narrower drive head. This wasn't a standard format, so it's not going to be readable unless you use the same software to read it back. (Fdformat did this.) These diskettes will also be unreadable in a standard double density (40 track) drive.


Mike

Definitely some handy info there, though I'll confess to already knowing the differences between the older and newer drives (head width). I have actually looked at the Wikipedia article on floppy disk formats just the other day and found it "must be incomplete" on the basis of "DSDD floppies being 1.2mb" (which while I now know to be false, before today I did not).

I do though have a disk here which is labeled, on the original sticker:
-DSDD/DFDD
-96 T.P.I.

(the label is bilingual English/French explaining DFDD)

As far as I can tell, this combination doesn't exist. If the disk is formatted to 1.2mb it has about 100k usable space because of "bad sectors", formatting to 160k causes it to work seemingly properly but a 160k disk at 96tpi? I imagine the drive is using whatever the "default" track per inch preference is so the fact the disk "can support up to 96tpi" is kind of useless.

I'm just trying to figure out what this disk was intended for. This particular disk actually appears to have originally contained software, "Axiom Educator 940".

How do we get TPI into tracks per side?

Chuck(G)
September 13th, 2009, 10:56 AM
How do we get TPI into tracks per side?

I despise the term "track" when what one really means is "cylinder"--the only time they are equivalent is when we're talking about single-sided media. Generally 48 tpi = 40 cylinder, 96 = 80 cylinder, 100 tpi = 77 cylinder. While 48 and 96 share the same "track 0" position, 100 does not.

If you want to fool around with quad-density recording on DD diskettes using a 1.2MB drive, try the attached driver.

mbbrutman
September 13th, 2009, 11:02 AM
It's far more complicated than that, Mike. Not only the coercivity of the material (e.g. Iron oxide vs. Barium ferrite), but the thickness of the coating (at higher data rates, a too-thick coating increases bit-shift issues), the particle size (must be small enough to support smaller bit cells) and the "loading" or the ratio of magnetic material to binder (high density diskette generally have much lower loading, which is one reason that their coatings appear to be almost transparent).

A new degaussed 5.25" HD floppy can sometimes be used in a pinch as DD media. When I get one mixed into a batch of DD media for conversion, I get sweaty palms, but most often, they do seem to work, even after 20 years of sitting around.

As far as "standard" formats go, the PC 720K 3.5" format will work fine on a 1.2MB drive using DD diskettes, provided that you have a driver to overcome the stupidity of the BIOS. Lots of vendors made 80 cylinder DD (sometimes called QD) drives and you could buy diskettes that were verified for QD use. There were a few "clone" BIOSes that could handle 720K 5.25" in a 1.2M drive without any special software.

All in all, I admire NEC's 9800 series of PCs. They started with 8" and moved to 5.25" and then to 3.5"--with all having exactly the same logical format--all spin at 360 RPM and use the same data rate.

Chuck,

There comes a point where one has to resist being overly verbose and beating a subject to near death. For the purposes of this conversation (paraphrased as 'I've got some bad diskettes') highlighting the fact that the material is different and has different properties was probably sufficient. Hence, I didn't go further ..


Mike

krebizfan
September 13th, 2009, 11:14 AM
As far as I can tell, this combination doesn't exist. If the disk is formatted to 1.2mb it has about 100k usable space because of "bad sectors", formatting to 160k causes it to work seemingly properly but a 160k disk at 96tpi? I imagine the drive is using whatever the "default" track per inch preference is so the fact the disk "can support up to 96tpi" is kind of useless.

I'm just trying to figure out what this disk was intended for. This particular disk actually appears to have originally contained software, "Axiom Educator 940".



Those disks were intended for a system that had a 720kB 5.25" drive. The Tandy 2000 was probably most common model that shipped with such a drive but lots of other systems had one before the "HD" 1.2 MB format got established.

kishy
September 13th, 2009, 11:22 AM
I despise the term "track" when what one really means is "cylinder"--the only time they are equivalent is when we're talking about single-sided media. Generally 48 tpi = 40 cylinder, 96 = 80 cylinder, 100 tpi = 77 cylinder. While 48 and 96 share the same "track 0" position, 100 does not.

If you want to fool around with quad-density recording on DD diskettes using a 1.2MB drive, try the attached driver.

Properly naming/labeling things is important, though in my case I don't know what I mean. My understanding (though easily and likely flawed) is that sectors go back-to-back inside of tracks, and that a track is a circular "path" around the disk, and that a cylinder refers to some unknown alternate way of referring to tracks. I remember looking that up and having limited luck finding a detailed description when I was trying to understand exactly where to park the heads on an RLL drive (some park utils asked for it as a track, some as a cylinder, and the number was different depending on which it asked for).

77 cylinders is...an 8 inch floppy?

Driver downloaded; will tinker with it at some point. Given that I'm currently working with my "patented computer-on-a-tray-table, boots-off-98se-boot-floppy with no nonremovable storage" computer, this might prove somewhat difficult, but I'll find a way.


Chuck,

There comes a point where one has to resist being overly verbose and beating a subject to near death. For the purposes of this conversation (paraphrased as 'I've got some bad diskettes') highlighting the fact that the material is different and has different properties was probably sufficient. Hence, I didn't go further ..


Mike

Chuck, I actually never saw the post Mike replied to...sorry if I seemed to disregard it.

Mike, perhaps we define "overly verbose" differently. I have yet, in all my travels of the vast internet, to find an explanation of floppy disk drives and floppy disk media that completely, clearly and **in language that I will not then have to go and immediately research, sending me on a wild goose chase** gives me an understanding that prevents such misunderstandings as "DSDD = 1.2MB". I am by no means criticizing your input in this thread - I am explaining why I don't already "get it" and as a result why I still don't "get it" entirely.

kishy
September 13th, 2009, 11:29 AM
Those disks were intended for a system that had a 720kB 5.25" drive. The Tandy 2000 was probably most common model that shipped with such a drive but lots of other systems had one before the "HD" 1.2 MB format got established.

Ohh, alright. Thanks.
Now the question is, is it my HD drives not supporting 720k, or is it the DOS 7 format command not supporting 720k (or is it both?)

I try format b: /f:720 and it says not supported.

mbbrutman
September 13th, 2009, 11:37 AM
Mike, perhaps we define "overly verbose" differently. I have yet, in all my travels of the vast internet, to find an explanation of floppy disk drives and floppy disk media that completely, clearly and **in language that I will not then have to go and immediately research, sending me on a wild goose chase** gives me an understanding that prevents such misunderstandings as "DSDD = 1.2MB". I am by no means criticizing your input in this thread - I am explaining why I don't already "get it" and as a result why I still don't "get it" entirely.

That is fine but I think when we start throwing out the chemical composition of the magnetic layer or the ratio of binder to magnetic material we have probably gone too far. For the purposes of this thread it is enough to note that the material is different and thus requires different levels of magnetic force to manipulate.

I don't think I misled in the statement that Chuck was replying to and the elaboration is interesting, but the phrase "It's far more complicated than that, Mike" kind of irks me because it presumes that I don't know that it is more complicated and that I am leaving out something important.

If somebody doesn't stop at a sensible point, it will turn into a chemistry and industrial engineering class, which is what happens over at the Classiccmp mailing list. Am I to respond next with a related physics lesson? (Don't worry - I can't.)

kishy
September 13th, 2009, 11:43 AM
That is fine but I think when we start throwing out the chemical composition of the magnetic layer or the ratio of binder to magnetic material we have probably gone too far. For the purposes of this thread it is enough to note that the material is different and thus requires different levels of magnetic force to manipulate.

I don't think I misled in the statement that Chuck was replying to and the elaboration is interesting, but the phrase "It's far more complicated than that, Mike" kind of irks me because it presumes that I don't know that it is more complicated and that I am leaving out something important.

If somebody doesn't stop at a sensible point, it will turn into a chemistry and industrial engineering class, which is what happens over at the Classiccmp mailing list. Am I to respond next with a related physics lesson? (Don't worry - I can't.)

Lol, alright, point taken (and agreed upon).
Basically, this whole business of tracks cylinders inches sides densities...it's all a jumbled mess in my head (and maybe that's how it is supposed to be, maybe this never made sense to anyone and trying to understand it is futile?)

It's probably a whole lot simpler than I make it. Similar story with how I (didn't) learn multiplication in grade school...I had a war with the teacher about how memorization is NOT learning, and that I wanted to learn how to do it properly, and in order to do that I should not be memorizing the results but instead memorizing the process.

As a result, I was never taught multiplication. Completely unrelated to the topic at hand, but might give someone a laugh, so there it is.

per
September 13th, 2009, 11:52 AM
Lol, alright, point taken (and agreed upon).
Basically, this whole business of tracks cylinders inches sides densities...it's all a jumbled mess in my head (and maybe that's how it is supposed to be, maybe this never made sense to anyone and trying to understand it is futile?)

It's probably a whole lot simpler than I make it. Similar story with how I (didn't) learn multiplication in grade school...I had a war with the teacher about how memorization is NOT learning, and that I wanted to learn how to do it properly, and in order to do that I should not be memorizing the results but instead memorizing the process.

As a result, I was never taught multiplication. Completely unrelated to the topic at hand, but might give someone a laugh, so there it is.

My understanding is as follows:
48tpi DD = Double Density, 160KB/180KB/320KB/360KB
96tpi HD = High Density, 1.2MB

However, HD disks won't allways format correctly if formated as DD disks. In fact, most HD disks I have tried reported loads of bad sectors when I tried it. In the same manner, DD disks can't be formated as HD disks.

About your 96tpi DD disks, I think those may be a hybrid, capable of being formated as either HD or DD. Do those disks give you errors when you try to read them?

the format command you should be using goes as follows:

FORMAT B: /F:[size] /U

krebizfan
September 13th, 2009, 12:01 PM
Ohh, alright. Thanks.
Now the question is, is it my HD drives not supporting 720k, or is it the DOS 7 format command not supporting 720k (or is it both?)

I try format b: /f:720 and it says not supported.

Your drive and bios may not support it. Unfortunately, a relatively uncommon format from a decade earlier will fall prey to the relentless effort to save fractions of a penny.

There were some 5.25" drives that did support both the 1.2 MB and 720kB formats with the ability to easily shift tpi and rpm as needed for disks. Specialized drivers would probably also be needed. I hope someone else can recommend methods that work.

I hesitate to point to the following web page since if the author is a poster here, the author is much better suited to answer questions:

http://www.oldskool.org/disk2fdi/525HDMOD.htm

But if you are lucky, you might be able to modify your drive to read the quad-density disks.

Chuck(G)
September 13th, 2009, 12:05 PM
77 cylinders is...an 8 inch floppy?

While 77 cylinders is a standard 8" format, there exists an older 5.25" format, recorded at 100 tpi with 77 cylinders. Sometimes, it's called a "Micropolis" format, after the manufacturer that pioneered it, other manufacturers made the drives too. The Tandon TM-100-4M ("M" for Micropolis; a TM-100-4 is a 96 tpi drive) is one such drive. Commodore used the drives briefly.

Mike, forgive me for going into too much detail. I'd assumed that the reason for these discussions was to educate--why would one collect old gear if not to understand it? Maybe I don't understand this collecting business...

mbbrutman
September 13th, 2009, 12:15 PM
Chuck - I don't think I got irked by the info. I think I got irked that the implication was that I left out something important to the immediate discussion.

And the broader question is, where do we draw the line on what's an appropriate level of detail? This thread is by far and way more interesting that many of our 'my PC is broken' threads, but at what point does the extra become noise? ClassicCmp is a perfect example of people making this unreadable for the sake of completeness ..

Fallo
September 13th, 2009, 12:33 PM
Ohh, alright. Thanks.
Now the question is, is it my HD drives not supporting 720k, or is it the DOS 7 format command not supporting 720k (or is it both?)

I try format b: /f:720 and it says not supported.

What's going on here is that 720k 5.25" disks are not a standard format on PCs. The /f:720 option is intended for 3.5" disks, so FORMAT will refuse to make a 5.25" disk at that capacity. There are third-party programs that will format 5.25" 720k disks.

HD drives themselves are perfectly capable of using quad-density floppies, which are just 80-track disks at the DD bit rate. Tandy 2000s aside, QD was used by some CP/M machines as well as Commodore 8050 and 8250 drives.

per
September 13th, 2009, 01:20 PM
What's going on here is that 720k 5.25" disks are not a standard format on PCs. The /f:720 option is intended for 3.5" disks, so FORMAT will refuse to make a 5.25" disk at that capacity. There are third-party programs that will format 5.25" 720k disks.

HD drives themselves are perfectly capable of using quad-density floppies, which are just 80-track disks at the DD bit rate. Tandy 2000s aside, QD was used by some CP/M machines as well as Commodore 8050 and 8250 drives.

Maybe that's why all the disks reports bad sectors when formated on a PC? What if all the disks has been formated in (and for) another system, and that disk-format confused the FORMAT program supplied by DOS?

Try to format one of the DD 48tpi ones using the command:

FORMAT B: /F:360 /U

Chuck(G)
September 13th, 2009, 01:49 PM
HD drives themselves are perfectly capable of using quad-density floppies, which are just 80-track disks at the DD bit rate. Tandy 2000s aside, QD was used by some CP/M machines as well as Commodore 8050 and 8250 drives.

Didn't the DG One also use 720K 5.25"? (That's one portable you don't see much about here, BTW)

kishy
September 13th, 2009, 02:02 PM
Kishy loves replies to read and reply to :)


My understanding is as follows:
48tpi DD = Double Density, 160KB/180KB/320KB/360KB
96tpi HD = High Density, 1.2MB

However, HD disks won't allways format correctly if formated as DD disks. In fact, most HD disks I have tried reported loads of bad sectors when I tried it. In the same manner, DD disks can't be formated as HD disks.

About your 96tpi DD disks, I think those may be a hybrid, capable of being formated as either HD or DD. Do those disks give you errors when you try to read them?

the format command you should be using goes as follows:

FORMAT B: /F:[size] /U

The "Cross-formatting" (HD to DD or DD to HD) kind of makes sense...the physical media, at least as I see it, doesn't correspond to the locations that the drive will try to access (yay or nay?)

The 96tpi DD disk (it looked like I had two but it was because they both had the same brand label on them, but only one is actually 96tpi DD) doesn't seem to want to work. I haven't tried putting anything on it and then trying to take it off, but logic says that would probably work fine because the same drive is doing the writing and reading, and it would only write to areas that it thinks are good.

Depending on what format I try to force on it, the "bad sectors" as detected by Scandisk will vary, but there are ALWAYS a lot of them. It's obvious that either a) the disk is actually damaged, b) the wrong format is being used resulting in those "fake" bad sectors or some sort of mix of both.

I'm not sure I want to try an unconditional format...if it is refusing to do it, wouldn't that possibly result in drive damage if the drive was instructed to, for example, seek to a location it doesn't know how to seek to (for example smash the r/w heads into something internally)? Obviously that's less catastrophic for a floppy drive which moves slowly compared to a hard drive, but still not good.


Your drive and bios may not support it. Unfortunately, a relatively uncommon format from a decade earlier will fall prey to the relentless effort to save fractions of a penny.

There were some 5.25" drives that did support both the 1.2 MB and 720kB formats with the ability to easily shift tpi and rpm as needed for disks. Specialized drivers would probably also be needed. I hope someone else can recommend methods that work.

I hesitate to point to the following web page since if the author is a poster here, the author is much better suited to answer questions:

http://www.oldskool.org/disk2fdi/525HDMOD.htm

But if you are lucky, you might be able to modify your drive to read the quad-density disks.

About modifying the drive(s), none of mine are Teac (Toshiba, Fujitsu, Panasonic, Canon/IBM, Chinon) so I'm a bit hesitant to start exploring that quite yet.

As one of the replies after yours states it looks like the format command /f:720 refers exclusively to 3.5" 720k disks, which are far more common it would seem (I actually have some of them, bought them new when I was younger...3 out of the set of 10 still work).

I wonder...I have a few Super-I/O cards, I wonder if the floppy controllers on any of them support 720k 5.25" formatting. Something to investigate in the future...those cards are never as simple to set up as they appear.

The motherboard I am using for this offers the following options for floppy drives in the BIOS:
-360K , 5.25 in.
-1.2M , 5.25 in.
-720K , 3.5 in.
-1.44M, 3.5 in.
(surprisingly, also this one:)
-2.88M, 3.5 in.


While 77 cylinders is a standard 8" format, there exists an older 5.25" format, recorded at 100 tpi with 77 cylinders. Sometimes, it's called a "Micropolis" format, after the manufacturer that pioneered it, other manufacturers made the drives too. The Tandon TM-100-4M ("M" for Micropolis; a TM-100-4 is a 96 tpi drive) is one such drive. Commodore used the drives briefly.

Mike, forgive me for going into too much detail. I'd assumed that the reason for these discussions was to educate--why would one collect old gear if not to understand it? Maybe I don't understand this collecting business...

Are there any specific advantages to the 5.25" 77 cylinder 100tpi format? I imagine it's useless without hardware support but interesting to know.

Collecting - if I may cut in between you two - can be for many reasons. I don't collect, I use. I have no specific attachment to older computers (and why would I, I was born in 1989) but I find them interesting...I like the challenge they can provide, the way they make me use my brain. I also enjoy dealing with intelligent, friendly, **interested** people when I have an issue or comment of some kind. I went to a computer store that was rumoured to have some older hardware and after the +1 hour trip was told they got rid of it all (but that I could come back in a few days and get some anyway?) rather inconsiderately and the person behind the counter clearly could not care less about the equipment he works on or the people he deals with. How could someone WORK WITH COMPUTERS and clearly hate them so much?

Stay away from the Second Infinite Byte in Windsor, Ontario, Canada - their staff are disrespectful, have a marginal amount of knowledge, and will trash talk you after you leave (as I witnessed when a customer left with their machine).


Chuck - I don't think I got irked by the info. I think I got irked that the implication was that I left out something important to the immediate discussion.

And the broader question is, where do we draw the line on what's an appropriate level of detail? This thread is by far and way more interesting that many of our 'my PC is broken' threads, but at what point does the extra become noise? ClassicCmp is a perfect example of people making this unreadable for the sake of completeness ..

Interesting is generally what I aim for, so it would appear I'm succeeding in that regard.


What's going on here is that 720k 5.25" disks are not a standard format on PCs. The /f:720 option is intended for 3.5" disks, so FORMAT will refuse to make a 5.25" disk at that capacity. There are third-party programs that will format 5.25" 720k disks.

HD drives themselves are perfectly capable of using quad-density floppies, which are just 80-track disks at the DD bit rate. Tandy 2000s aside, QD was used by some CP/M machines as well as Commodore 8050 and 8250 drives.

I figured it might be something about that (720k 3.5" disks), but was hoping maybe the format command could use the same switch for either type. Apparently not.

I've probably missed something in this thread, but are "QD" disks actually different physically, or is it simply the recording method that differs?

per
September 13th, 2009, 02:11 PM
I'm not sure I want to try an unconditional format...if it is refusing to do it, wouldn't that possibly result in drive damage if the drive was instructed to, for example, seek to a location it doesn't know how to seek to (for example smash the r/w heads into something internally)? Obviously that's less catastrophic for a floppy drive which moves slowly compared to a hard drive, but still not good.

You are misunderstanding something there:

An unconditional format aren't dangerous to the drive at all. The only difference betwen unconditional format and normal format is that normal format tries to verify/write to the existing disk layout while an unconditional format will rewrite the disk layer before starting a normal format. Because of this, "un-format" information can't be saved to the disk, and in cause you had some imporiant files on the disk when it was "accidentally" formated, you won't be able to restore them.

Of course you are not trying to "accidentally" format any of the disks, so an unconditional format is totally safe in your cause.

(the R/W head of the floppy drive slides on a rail. When it reaches the end of this rail, the head can't possibly move any futher. And, when it comes to floppy disks, the heads are touching the surface of the disks all the time, soyou don't have to worry about disk carsh.)

kishy
September 13th, 2009, 02:52 PM
You are misunderstanding something there:

An unconditional format aren't dangerous to the drive at all. The only difference betwen unconditional format and normal format is that normal format tries to verify/write to the existing disk layout while an unconditional format will rewrite the disk layer before starting a normal format. Because of this, "un-format" information can't be saved to the disk, and in cause you had some imporiant files on the disk when it was "accidentally" formated, you won't be able to restore them.

Of course you are not trying to "accidentally" format any of the disks, so an unconditional format is totally safe in your cause.

(the R/W head of the floppy drive slides on a rail. When it reaches the end of this rail, the head can't possibly move any futher. And, when it comes to floppy disks, the heads are touching the surface of the disks all the time, soyou don't have to worry about disk carsh.)

Oh, that's good to know then...thanks. I do know the head is on a rail, but I wasn't sure if it's possible to knock things out of alignment.

However, in this case, isn't it true that even an unconditional format won't format the disks to 720k, since the format command doesn't actually support 720k 5.25" disks?

Fallo
September 13th, 2009, 03:03 PM
As one of the replies after yours states it looks like the format command /f:720 refers exclusively to 3.5" 720k disks, which are far more common it would seem (I actually have some of them, bought them new when I was younger...3 out of the set of 10 still work).

3.5" DD disks were much more widely used than you might think. Aside from PCs, they would include the MSX, Mac, Apple II, Lisa, Amiga, Atari ST, Commodore 1581 drives, HP 150, and also things like music synthesizers, embroidery machines, and word processors.


I wonder...I have a few Super-I/O cards, I wonder if the floppy controllers on any of them support 720k 5.25" formatting. Something to investigate in the future...those cards are never as simple to set up as they appear.

Since QD disks use the DD bitrate, any PC controller can use them. You just need an 80-track drive.


I figured it might be something about that (720k 3.5" disks), but was hoping maybe the format command could use the same switch for either type. Apparently not.

FORMAT can only use the disk types supported by DOS, which do not include 5.25" 720k.


I've probably missed something in this thread, but are "QD" disks actually different physically, or is it simply the recording method that differs?

It's just the recording method; there's no physical difference with DD disks. Usually, QD disks were tested more rigorously because it was thought that 80-track formatting was more demanding on the disk. I actually have two boxes of QD disks that I use on my 5150 as 360k disks.

Most DD disks will format to 80 tracks with no problems, except perhaps for some no-name brands, which as Chuck mentioned, tend to have lower-quality media.

per
September 13th, 2009, 03:08 PM
Oh, that's good to know then...thanks. I do know the head is on a rail, but I wasn't sure if it's possible to knock things out of alignment.

However, in this case, isn't it true that even an unconditional format won't format the disks to 720k, since the format command doesn't actually support 720k 5.25" disks?

There is almost nothing that can get the head out of alginment unless you drop the drive or physically alter the head manually.

Well, as I said, an Unconditional format is simply a "low-level" format of the floppy disk, and absolutely all data (including the controll data) is being rewritten. Since your disks has been formated a way they weren't supposed to, the magnetic data is all mixed up and an Unconditional format is actually the only way to fix them.

About 720KB 5.25" disks and the format utility, the format program isn't what's limiting your posibilities. when you format a disk while using the "/F:x" parameter, the Format utility checks with the BIOS to see if the drive actually IS what you specify. If the BIOS don't agree, you'll get an error. (I think. It may also check the drive itself without going through the BIOS.)

However, there is one way to override this (IIRC), and that is to manually specify the number of heads/cylinders(tracks-per-head)/sectors into the format utility. This should override the BIOS, and hopefully format it to what you want.

Just be aware that you can get into some problems by formating a 5.25" disk to 720KB. This wasn't/isn't usual for PC's, and many programs will either think that the disk is a 720KB 3.5" floppy or a 360KB 5.25" floppy.

Ole Juul
September 13th, 2009, 03:32 PM
I originally got a lot of information from Scott Mueller's Repair book. IIRC, it explains most of what I've seen here. Regarding physical writing of the disks, this Floppy Primer (http://www.accurite.com/FloppyPrimer.html) page explains, among other things, azimuth and radial alignment. I thought this might be of interest here.

I've also had a lot of educational fun playing with different formats. Programs such as the MS format command obviously have their own agenda, but there are other programs out there which allow you the freedom to make your own choices. My favourite is FreeForm, a menu-driven floppy disk formatter. It's a 91K download from Simtel.Net (http://www.eunet.bg/simtel.net/msdos/diskutil-pre.html). Look for ffrm231a.zip. Almost any combination of formatting parameters can be chosen using that program.

Because of the menus, FreeForm is very educational (to me) but for a modern formatter I use, and recommend, the one from FreeDos (http://www.freedos.org/). Look for FMT091v.ZIP here (http://www.ibiblio.org/pub/micro/pc-stuff/freedos/files/dos/format/). It will let you specify tracks and sectors and, AFAIK it is written solely for the benefit of the users. It also has no licensing encumbrances.

Didn't MicroSoft use 1.7Mb distribution diskettes at one point? I seem to recall that one purpose was that you couldn't copy them using MS's own software. Of course those were 3.5" diskettes, but I'm sure the same trick has been used for 5.25s. You can certainly format 1.2s to 1.4, although I notice that the reliability goes down.

Chuck(G)
September 13th, 2009, 03:37 PM
Are there any specific advantages to the 5.25" 77 cylinder 100tpi format? I imagine it's useless without hardware support but interesting to know.

None that I'm aware of; they were an early 5.25" format and there were comparatively few systems that used them. At Durango, we recorded GCR using a WD1781 controller and a whole bunch of glue ICs and got about 960K per 100 tpi 5.25" floppy. Had the 96 tpi drives been available, we would have happily used those instead--the Micropolis drives were glacially slow when it came to seeking.

There are some small differences in the connector assignments, but generally the drives are electrically compatible with the PC floppy interface.

Sort of an interesting evolutionary dead end, like 3.25" diskettes and Drivetec floppies.


Didn't MicroSoft use 1.7Mb distribution diskettes at one point? I seem to recall that the one purpose was that you couldn't copy them using MS's own software. Of course those were 3.5" diskettes, but I'm sure the same trick has been used for 5.25s. You can certainly format 1.2s to 1.4, although I notice that the reliability goes down.

Both IBM and Microsoft used "extreme" formats. Google "DMF" and "XDF" formats--there's plenty of information out there on them. Both IBM and MS offered to send you conventionally-formatted floppies if you yelled loud enough.


(I don't really collect either, but I have a ton of old stuff hanging around from having been in this racket for too long. Even if I could find the systems that I used when I was young, I couldn't afford to run them...)

kishy
September 14th, 2009, 11:27 AM
There's pretty much too much stuff there for me to specifically address (I'm sure you all understand).

Basically, I don't have any more questions...you've been that thorough :)

About 1.7 DMF floppies - yes, MS used them for Win95 and possibly other releases on floppies. For the person today who may be trying to write those disks, I advise you to pick disks you won't care to lose...they will NOT be reliable when formatted back to 1.44 afterwards!

Ole Juul
September 14th, 2009, 04:57 PM
About 1.7 DMF floppies - yes, MS used them for Win95 and possibly other releases on floppies. For the person today who may be trying to write those disks, I advise you to pick disks you won't care to lose...they will NOT be reliable when formatted back to 1.44 afterwards!
I doubt that the media is actually damaged and I'm fairly certain that the disc would be perfectly good if you wiped it. Of course if you don't have anything to do that with then there might be a problem, I don't know about that.

kishy
September 14th, 2009, 05:42 PM
I doubt that the media is actually damaged and I'm fairly certain that the disc would be perfectly good if you wiped it. Of course if you don't have anything to do that with then there might be a problem, I don't know about that.

I'm referring to starting with a 1.44mb floppy disk, formatting it to 1.7 DMF for holding files during an install, then formatting back to 1.44 afterwards. Every disk I used in that set (I installed Win95 via floppies once just for the experience...what a waste) was trash afterwards. Basically, you'd format the disk back, put a file on it, then pop it in a few minutes later and the file is gone (or heavily corrupted).

Ole Juul
September 14th, 2009, 05:50 PM
I just took an old Mackintosh 3.5" disk which, of course, wouldn't read on a DOS system. Then I formatted it to 1.7M and wrote a file to it and ran chkdsk. All was fine. Then I formatted it to 1.4M and wrote a file to it and ran chdsk. All is still fine! It is indeed possible to format to 1.7 and then go back to 1.44. This was all done in the drive and I did not need to remove the disk to wipe it.

The program I used was FreeForm v2.31. I tried reformatting with FreeDos Format v1.0 and it appeared to work but upon writing a file or running chkdsk it complained. So, it looks like it all depends upon the formatting program. :)

I have heard people complaining about inadequacies of the MS format program, but I am surprised that the FreeDos program has the same bug. However, I am not completely sure that the FreeDos program would not be able do it if given the correct parameters. It has several ways of using it. FreeForm is just a no-brainer that's why I used that.

kishy
September 14th, 2009, 06:28 PM
I just took an old Mackintosh 3.5" disk which, of course, wouldn't read on a DOS system. Then I formatted it to 1.7M and wrote a file to it and ran chkdsk. All was fine. Then I formatted it to 1.4M and wrote a file to it and ran chdsk. All is still fine! It is indeed possible to format to 1.7 and then go back to 1.44. This was all done in the drive and I did not need to remove the disk to wipe it.

The program I used was FreeForm v2.31. I tried reformatting with FreeDos Format v1.0 and it appeared to work but upon writing a file or running chkdsk it complained. So, it looks like it all depends upon the formatting program. :)

I have heard people complaining about inadequacies of the MS format program, but I am surprised that the FreeDos program has the same bug. However, I am not completely sure that the FreeDos program would not be able do it if given the correct parameters. It has several ways of using it. FreeForm is just a no-brainer that's why I used that.

I suspect there's more to it than the program...it's probably much more drive and media dependent. I used WinImage for the ones I did.

Chuck(G)
September 14th, 2009, 06:47 PM
There's no basis that I can think of for 1.7M not formatting to 1.44M again. Heck, I reformat disks to all sorts of weird layouts all of the time with no problem.

On the other hand, most new 1.44M media is pretty terrible--and the way drives are mounted in cases nowadays also makes them dust magnets, leading to reading/writing problems.

kishy
September 14th, 2009, 06:59 PM
There's no basis that I can think of for 1.7M not formatting to 1.44M again. Heck, I reformat disks to all sorts of weird layouts all of the time with no problem.

On the other hand, most new 1.44M media is pretty terrible--and the way drives are mounted in cases nowadays also makes them dust magnets, leading to reading/writing problems.

It's not that it didn't format back...it did. It just didn't actually hold any of the data anymore (which would suggest the process of 1.44 -> 1.7 -> 1.44 physically stressed the media to the max). They were pretty much brand new disks (less than a year old, a couple of them used briefly and reliably) in a brand new drive at the time.

Chuck(G)
September 14th, 2009, 07:40 PM
It's not that it didn't format back...it did. It just didn't actually hold any of the data anymore (which would suggest the process of 1.44 -> 1.7 -> 1.44 physically stressed the media to the max). They were pretty much brand new disks (less than a year old, a couple of them used briefly and reliably) in a brand new drive at the time.

I think you have a mistaken idea of how media is formatted and written. When you format a diskette, every bit on the track is written, used or not. The differences in formats are primarily the placement of the address marks. Anything not used on a track is filled with "filler" bytes. So, there's really nothing different happening when you format a DMF or XDF floppy, other than the address marks (which are data patterns that are missing one or two "clock" bits are in a different spot.

As a roughly analogous situation, this is like saying that once you record "I am Curious (yellow)" on a VHS cart, the tape refuses to hold a copy of "Rebecca of Sunnybrook Farm". It may be, but there's no good technical reason for it. :)

Ole Juul
September 14th, 2009, 07:43 PM
physically stressed the media to the max What does that actually mean? With all due respect, that sounds like some newfangled physics to me. :)

If there is some kind of drive problem like Chuck(G) hinted at then there's nothing you can do about that. If there is residual magnetization on the media it can be completely removed by wiping the disk. By wiping the disk, I mean using a demagnetizer such as used for tape. This is usually done in the audio world because you cannot record on previously used tape without having higher background noise than on fresh tape. That is easily solved with a demagnetizer (ie wiping it) and the media is then pretty much as good as new. The erase head, you see, is not very good even in the expensive heavy duty 16 track machines. The same problem exists for floppys but digital recording is much less critical. Where problems come in (apart from dirt and physical damage) is the possible inaccuracy of tracking. That can cause intermittent problems when the signal induced is borderline. In any case, wipe the disk and you're magnetically back to new again.

PS: Tape demagnetizers have been discussed here before and there are lots of cheap ones around. Radio shack sells them.

kishy
September 15th, 2009, 02:04 PM
I am very easily and quite likely not understanding something with regards to this, but using a floppy drive (and no other tools, besides of course the software to use said drive) it is not possible to get one of those disks to come back.

I am of course referring to my own experiences with my own disks.
From my perspective, those disks became damaged because they were no longer able to be recovered using "just" a floppy drive.

Much like how a CRT TV with no degauss function (which has been discoloured by a magnet) will be "broken" until someone uses one of those degausser tools on it.

Chuck(G)
September 15th, 2009, 02:52 PM
Okay, two items of clarification.

First, are these "factory" DMF diskettes? In other words, are they ones you formatted yourself or ones that someone else (e.g. Microsoft) formatted? The reason I ask is that it was the practice of some duplication houses to crank the write current way up, making it more difficult to reuse disks without degaussing.

Second, are you re-formatting them under DOS and not Windows? Windows formatting involves a check of an existing format before laying down a "hard" format.

Otherwise (I just tried it), I have no problems formatting and then reformatting DMF disks with a standard DOS 80x2x18x512 format.

per
September 15th, 2009, 03:14 PM
I am very easily and quite likely not understanding something with regards to this, but using a floppy drive (and no other tools, besides of course the software to use said drive) it is not possible to get one of those disks to come back.

I am of course referring to my own experiences with my own disks.
From my perspective, those disks became damaged because they were no longer able to be recovered using "just" a floppy drive.

Much like how a CRT TV with no degauss function (which has been discoloured by a magnet) will be "broken" until someone uses one of those degausser tools on it.

AT LEAST try an unconditional format (/U parameter) with the /F:360 parameter included. If that doesn't work, you need a bulk ereaser.

kishy
September 15th, 2009, 03:44 PM
Okay, two items of clarification.

First, are these "factory" DMF diskettes? In other words, are they ones you formatted yourself or ones that someone else (e.g. Microsoft) formatted? The reason I ask is that it was the practice of some duplication houses to crank the write current way up, making it more difficult to reuse disks without degaussing.

Second, are you re-formatting them under DOS and not Windows? Windows formatting involves a check of an existing format before laying down a "hard" format.

Otherwise (I just tried it), I have no problems formatting and then reformatting DMF disks with a standard DOS 80x2x18x512 format.

I'm pretty sure I specified they were "factory" 1.44MB disks, not DMF. I formatted them TO dmf then used them for the win95 install, then formatted back to 1.44 and had issues.

I formatted "under" Windows (XP) but, as I said, using WinImage. Given that similar operations of 1.44 -> 720 -> 1.44 go over with no issue (assuming of course I tape off the second hole), I'd say the issue is the media I used just doesn't stand up to it. Anything involving a tool outside of my computer would be classed as "repair" to me, meaning the disks were in fact "broken" after the "1.44 to DMF then back to 1.44" thing.


AT LEAST try an unconditional format (/U parameter) with the /F:360 parameter included. If that doesn't work, you need a bulk ereaser.

per, I believe you may be confused (as would happen EASILY in this thread).
We are now on the topic of 3.5" 1.44MB media being formatted to and from DMF (1.7MB)

About those 5.25" disks, all of them are now performing exactly like they should (as 360k disks) except for that one...the "96tpi DSDD" disk. I'll give the unconditional format a try...right....NOW (powering on the "TV tray computer")

kishy
September 15th, 2009, 03:50 PM
Well per, it appears /u wins. (see what I did there?)

the "96tpi dsdd" disk took the 360k format like a champ, with no unusual noises or pauses, and there are now apparently zero bad sectors (the more I mess with this stuff, the more it looks like bad sectors simply represent an incorrect format)

per
September 15th, 2009, 03:51 PM
per, I believe you may be confused (as would happen EASILY in this thread).
We are now on the topic of 3.5" 1.44MB media being formatted to and from DMF (1.7MB)

About those 5.25" disks, all of them are now performing exactly like they should (as 360k disks) except for that one...the "96tpi DSDD" disk. I'll give the unconditional format a try...right....NOW (powering on the "TV tray computer")

Ok. I just didn't see when the topic changed.

You may try to use the following parameters instead of the /F: x parameter:

(/1 for one-sided media, skip it for two-sided media)
/T:tracks_per_side
/N:sectors_per_track

The Standard 1.44MB format of 3.5" disks uses 80 tracks/side and 18 sectors/track.
The Microsoft 1.68MB format (DMF) of 3.5" disks uses 80 tracks/side and 21 sectors/track.
For IBM XDF format, I have no idea. It may even be a non-standard layout, making it unable to format with the satnadard format program.

Chuck(G)
September 15th, 2009, 04:49 PM
For IBM XDF format, I have no idea. It may even be a non-standard layout, making it unable to format with the satnadard format program.

XDF is very different, using differently-sized sectors on each track; something that requires a little "trickery" to do with the standard PC controller.

IBM supplied a utility called, I think, XDFCopy to handle making duplicates.

Ole Juul
September 15th, 2009, 05:38 PM
kishi: Anything involving a tool outside of my computer would be classed as "repair" to me, meaning the disks were in fact "broken" after the "1.44 to DMF then back to 1.44" thing. You can think that way if you like, though I would think that it is the computer which is "broken" in that case. :) To me it is not reasonable to expect computers to do everything. That could just be a generational thing though. lol I have to rewrite the labels on my floppies when I want them to say something else, even though there is no reason that a floppy drive couldn't print too. It's just more practical to make drives with limited functionality and then do some things independently. Demagnetizing magnetic media is just one of those "outside" things which practitioners of magnetic recording have been doing for a long time - even if you haven't. Please don't take offense - I'm just pointing out that peripherals are an acceptable thing to many people. :)

I also don't wish to deny what has obviously been your experience. You could have a quality problem with your drive, or drives. "Broken" software is another avenue to explore. Not being familiar with MS-Windows, I can't comment directly on Winimage, but it is distinctly possible that it has some limitations. Not to put down MS, but they have been known to make some programming choices which may limit the users options.

kishy
September 15th, 2009, 06:18 PM
You can think that way if you like, though I would think that it is the computer which is "broken" in that case. :) To me it is not reasonable to expect computers to do everything. That could just be a generational thing though. lol I have to rewrite the labels on my floppies when I want them to say something else, even though there is no reason that a floppy drive couldn't print too. It's just more practical to make drives with limited functionality and then do some things independently. Demagnetizing magnetic media is just one of those "outside" things which practitioners of magnetic recording have been doing for a long time - even if you haven't. Please don't take offense - I'm just pointing out that peripherals are an acceptable thing to many people. :)

I also don't wish to deny what has obviously been your experience. You could have a quality problem with your drive, or drives. "Broken" software is another avenue to explore. Not being familiar with MS-Windows, I can't comment directly on Winimage, but it is distinctly possible that it has some limitations. Not to put down MS, but they have been known to make some programming choices which may limit the users options.

It just occurred to me that you PM'd me the other day and I forgot to reply...in essence, you're welcome :)

Very true about not expecting the computer to do everything, but a lot of this does come back to perspective. In my 'generation' of computing (which is, realistically speaking, 486-current), a lot of this "do it yourself" attitude was diminishing and automation was expected. One (of my perspective) would consider a floppy disk (or removable media in general) a zero-maintenance device, one which you use until it stops working easily/normally and then consider nonfunctional. That's not to say it actually isn't...in that case it is my perspective that is flawed.

Quality issues are quite likely, the one I was using at the time was brand new so understandably...it will be of significantly lower quality than a precision designed and built drive of, say, the early 1990s. I wouldn't put it past the media either though, again it was pretty much brand new and as has been stated in this thread they aren't made like they used to be.

WinImage is, in case you're not aware (it could go either way based on your reply) actually third party software which has - by far - better and more capabilities than the built in Microsoft (or whatever company they stole it from) formatting tools. That of course isn't to say MS drivers don't hamper operation of the drive (which I think is what you were hinting at).