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cruising
April 6th, 2014, 02:28 AM
When i format floppys, the head count (on screen) from 0 to 1 when each cylinder is done up to 39 cylinders. However, one of the disks did not count between 0-1, i just saw on screen that the cylinders was counting up to 39 while the heads was 0 all the way. Why did the formating doing that on just this floppy disk?

EDIT:

When it does that, the size of the floppy disk formats to 179712 Bytes free, and when it counts with heads it formats to 362496 free

Stone
April 6th, 2014, 03:30 AM
It's a single sided disk so it only formats with one head. :-)

cruising
April 6th, 2014, 04:19 AM
It's a single sided disk so it only formats with one head. :-)

Ah! thats pretty logical! so under 360 is single sided then? and 360 and above is DS?

EDIT:
But.. one thing thats not seamas to be correct, if im not wrong, it was a maxell or a M3 that formated single sided, and the rest of the very same (same box) formated as DS.
And the label on it says MD2-D and DS, HD

Stone
April 6th, 2014, 04:45 AM
DS, HD means High Density so you shouldn't be using those disks in a 360K drive anyway. They require a 1.2M High Density drive to work correctly.

cruising
April 6th, 2014, 05:30 AM
DS, HD means High Density so you shouldn't be using those disks in a 360K drive anyway. They require a 1.2M High Density drive to work correctly.

Yeah thats true, but these is all i have, and when i format them, they format to 360K. But they are not so stable to read after formating. fails sometime to read these floppies.

Stone
April 6th, 2014, 05:33 AM
That's why you shouldn't use them. You never know what you're going to get and how long it will last.

cruising
April 6th, 2014, 05:45 AM
That's why you shouldn't use them. You never know what you're going to get and how long it will last.

You mean that the floppys taking damage if i use them like that?

Stone
April 6th, 2014, 06:46 AM
No... THEY JUST DON'T WORK CORRECTLY!

cruising
April 6th, 2014, 07:33 AM
No... THEY JUST DON'T WORK CORRECTLY!

Dont scream, im new to this..

mbbrutman
April 6th, 2014, 08:44 AM
You might find this more helpful:

http://www.brutman.com/PCjr/diskette_handling.html

In short:


The original IBM PC from 1981 with DOS 1.x and singled side drives formats to 160KB per side. The geometry is 1 side, 40 tracks, 8 sectors per track. At 512 bytes per sector that works out to 160KB. You will rarely see disks in this format. Very old versions of DOS (2.1 and lower) are shipped this way to be compatible with the first IBM PCs. Some very old commercial software is shipped this way too.
A slightly newer PC with double sided drives can format to 320KB (2 sides, 40 tracks, 8 sectors per track) or 360KB (2 sides, 40 tracks, 9 sectors per track). The 320KB format is rare - you will usually see the 360KB format.
Later drives (3.5" or high density 5.25) have different sizes; see above, Wikipedia or Google. These are 720KB, 1.2MB, 1.44MB, etc.


If a floppy drive can't format track 0 it assumes that it has a single sided diskette. So you might have had a double sided diskette, but there was an error and the format routine adjusted. If it really is a double sided diskette and it is not damaged try cleaning the drive heads with a head cleaner and format again - many times these errors are just transient.

Stone
April 6th, 2014, 09:19 AM
Mike, he's using 1.2M HD media in a 360K DD drive. See post #5.

mbbrutman
April 6th, 2014, 09:33 AM
And the link I gave him covers that faux-pas exactly. He just needs to read through it and get a better understanding.

I think we need to be more patient with people and what we assume they know. It is probably better to point them at something more comprehensive than just quickly answer their questions. Which is why FAQs and Wiki articles works so well.

cruising
April 6th, 2014, 09:42 AM
You might find this more helpful:

http://www.brutman.com/PCjr/diskette_handling.html

In short:


The original IBM PC from 1981 with DOS 1.x and singled side drives formats to 160KB per side. The geometry is 1 side, 40 tracks, 8 sectors per track. At 512 bytes per sector that works out to 160KB. You will rarely see disks in this format. Very old versions of DOS (2.1 and lower) are shipped this way to be compatible with the first IBM PCs. Some very old commercial software is shipped this way too.
A slightly newer PC with double sided drives can format to 320KB (2 sides, 40 tracks, 8 sectors per track) or 360KB (2 sides, 40 tracks, 9 sectors per track). The 320KB format is rare - you will usually see the 360KB format.
Later drives (3.5" or high density 5.25) have different sizes; see above, Wikipedia or Google. These are 720KB, 1.2MB, 1.44MB, etc.


If a floppy drive can't format track 0 it assumes that it has a single sided diskette. So you might have had a double sided diskette, but there was an error and the format routine adjusted. If it really is a double sided diskette and it is not damaged try cleaning the drive heads with a head cleaner and format again - many times these errors are just transient.

I see! my FDD use 40 tracks and im trying to use floppys with 80 tracks if im not wrong, if so, i understand why it doesnt work properly! thanks for th link, it was some interesting reading.

And what does MD2-D means? MD is Mini-floppy Disk,but 2-D?

luvit
April 6th, 2014, 09:52 AM
Mike, in agreement, comprehensive answers are most valuable.
I just wanted to add it's easy to see some some vets to respond "search around the VFC site, it's been here a million times".
It can be an ugly mess to attempt to piece together fragnented (but valuable) thread responses unless you find just the right thread where there was thorough responses.

Sometimes we're assuming that that information should be easy to follow and still assumes they have a relatively-full laymen experience.
Some newer members don't know what to ask because they don't know what experience they are missing.
At times, we may have to ask them more questions for clarity before lobbing quick answers over the fence.

krebizfan
April 6th, 2014, 09:55 AM
I think some steps got skipped in all this:
Which operating system are you using?
Which computer model?
Which floppy drive model?
Are the disks reused? Do they look worn or does the disk sleeve have what looks like dust in it?

5.25" floppy drives can be trickier because there is also the Single Sided Quad Density (360kB) format used by Sharp and DEC (and a few others). Many drives have jumpers which can cause them to be in single sided mode even if the drive has two heads. Those are unlikely situations but sometimes one can get focused on the wrong cause and fail to get things working.

cruising
April 6th, 2014, 10:25 AM
I think some steps got skipped in all this:
Which operating system are you using?
Which computer model?
Which floppy drive model?
Are the disks reused? Do they look worn or does the disk sleeve have what looks like dust in it?

5.25" floppy drives can be trickier because there is also the Single Sided Quad Density (360kB) format used by Sharp and DEC (and a few others). Many drives have jumpers which can cause them to be in single sided mode even if the drive has two heads. Those are unlikely situations but sometimes one can get focused on the wrong cause and fail to get things working.

Im using DOS 3.20
IBM XT
Tandon TM100-2

Some is new unused, but 1.6M HDs, and some with no labels on that i think is regular DDs when they have a hub ring in center witch suppose to be on double density disks.
And i do have one of these quad density disks.

And if i have got this right, i should use DS,DD ?

Stone
April 6th, 2014, 11:08 AM
And if i have got this right, i should use DS,DD ?Yes, anything else will only cause more problems.

krebizfan
April 6th, 2014, 11:16 AM
Im using DOS 3.20
IBM XT
Tandon TM100-2

Some is new unused, but 1.6M HDs, and some with no labels on that i think is regular DDs when they have a hub ring in center witch suppose to be on double density disks.
And i do have one of these quad density disks

The ones with hub rings should be double density. If the disk had never been formatted before and it successfully formats, then the drive is working correctly. I don't remember if DOS 3.2 tried to keep an already formatted diskette with the same format so an ancient DOS 1 disk (single sided) would stay single sided. Don't bother trying the high density diskettes or any diskette showing signs of damage.

I think there were switches to force a 360kB double sided format on an already formatted disk but I don't remember the 3.2 specific method for it. I think "format a: /4" would be right but double check with documentation.

Chuck(G)
April 6th, 2014, 11:28 AM
I'm sorry that I haven't been following this thread. In later versions of DOS (but not Windows 9x; i.e. DOS 7+), FORMAT has a /U switch to force unconditional formatting, rather than try to re-verify the floppy. Thus, in DOS 6.22, you could FORMAT A: /U /F:360 to force a 40x2x9x512 format, no matter what the disk had been originally. Later versions (i.e. Windows 9x) assume that if you're specifying a format explicitly, you mean to unconditionally format the drive. In 2K/XP, the FORMAT command is a bit different--the system always tries to read the floppy and deduce something about it before formatting. I've had some success specifying the filesystem explicitly to force a low-level format; e.g., FORMAT A: /FS:FAT /N:9 /T:40

If you've got a bunch of disks to format, particularly if you have more than one drive, have a look at FORMATQM--just pop the floppies in and out--it's always low-level formatting--and there's a "PERFECT" switch to reject any disk with even one bad cluster.

cruising
April 6th, 2014, 11:29 AM
Yes, anything else will only cause more problems.

Ok thanks, then i know what i need to look for.

cruising
April 6th, 2014, 11:36 AM
The ones with hub rings should be double density. If the disk had never been formatted before and it successfully formats, then the drive is working correctly. I don't remember if DOS 3.2 tried to keep an already formatted diskette with the same format so an ancient DOS 1 disk (single sided) would stay single sided. Don't bother trying the high density diskettes or any diskette showing signs of damage.

I think there were switches to force a 360kB double sided format on an already formatted disk but I don't remember the 3.2 specific method for it. I think "format a: /4" would be right but double check with documentation.


Yes the ones with the hub rings (DDs) formats successfully and do work, and also the HDs successfully formats to 360k but is unstable reading, but now i know that i should never use a HD in a DD drive! And i dont think there is any wrong with the drive when it could read a already formted disk with DOS 2.xx on it, and it did even boot on that disk. But of some reason it does not boot on that disk anymore but can be read when booting to HD.

vwestlife
April 6th, 2014, 02:37 PM
If a floppy drive can't format track 0 it assumes that it has a single sided diskette. So you might have had a double sided diskette, but there was an error and the format routine adjusted.

I've seen that happen. If FORMAT encounters an error on track 0 side 1, then it assumes it is a single-sided disk and proceeds to format it as 180K single-sided. (If track 0 side 0 has an error, then it fails with the "Track 0 bad or disk unusable" message.)

modem7
April 7th, 2014, 12:03 AM
The ones with hub rings should be double density.
I am glad that you used the word, "should".
Right now, I am looking at a Fuji Film 5.25" 2S HD floppy that has a hub ring.

cruising
April 7th, 2014, 12:48 AM
I am glad that you used the word, "should".
Right now, I am looking at a Fuji Film 5.25" 2S HD floppy that has a hub ring.

Yeah, i was reading that some HD floppy also sometimes has that hub ring.

RWallmow
April 7th, 2014, 01:13 AM
I have never seen a HD with a hub-ring :rolleyes: Learn something new every day.

I have however never seen or heard of a DD without a hub ring, but you never know what you will find.

MikeS
April 7th, 2014, 05:58 AM
The thinner coating tends to make 5.25" HD diskettes slightly translucent.

Chuck(G)
April 7th, 2014, 08:56 AM
I have never seen a HD with a hub-ring :rolleyes: Learn something new every day.

I have however never seen or heard of a DD without a hub ring, but you never know what you will find.

Got samples of each--particularly the DD without rings. The DD case is interesting and can be laid squarely on two issues:

1. The motor on 5.25" drives is a DC motor and made controllable by software. 8" drives usually had mains-powered AC motors (but not all--later half-height ones sometimes used DC motors). If you insert a disk in a 5.25" when the motor power is off and the drive doesn't have the "spin on insertion" circuitry, much of the time, the hub area will get wrinkled and the floppy may not seat correctly.

2. Micropolis had their own clamping mechanism which did the hub-mangling thing better than any other drive until they modified the drive to turn on the motor when the door begins to close. We battled that one hard and one day, the factory rep showed up with a kit consisting of rings and a jig to install them on floppies. After that, they were standard features on Verbatim and Dysan floppies--and other manufacturers followed.

3. By the time the HD 5.25" drives showed up, the drive clamping problem had largely been solved, so there was no need for the rings on HD media, though some manufacturers initially put them on anyway.

vwestlife
April 7th, 2014, 09:16 AM
I have seen non-HD 5.25" floppies without the hub ring. However, they were all single-sided disks that were originally used with non-PC systems (Atari 8-bit, TRS-80, etc.). I have also encountered some disks where the hub ring came loose, so rather than risk it getting stuck in the drive, I just took it off, and the disk continued to work fine without it.

And I have encountered some 5.25" drives which tend to wrinkle the floppy if you yank down on the lever or door too quickly when the computer is turned off -- perhaps another reason why most manufacturers told you to wait until after turning on the computer to insert a disk (in addition to the potentially-data-corrupting electromagnetic spike that might occur when you first switch on the power).

Chuck(G)
April 7th, 2014, 10:10 AM
As a curious legacy item, note that 3.5" drives spin the motor briefly when a disk is inserted, just to get the metal hub indexed to the spindle mechanism.

Trixter
April 7th, 2014, 11:28 AM
The DD case is interesting and can be laid squarely on two issues:

It's nuggets like this that I'm glad I subscribe to this forum.

I'm curious what you thought of the 3.5" "HD hole" punching machines to "double your diskette capacity for free!". (Joking -- I know what you think of them.) One of the advertising blurbs at the time was "We wrote and read the diskette continuously for 30 days without a single byte of lost data!"... What the advert failed to mention was what happened when you tried to read that disk six months later.

I own a punching apparatus not for practical use but rather as a museum piece.

luvit
April 7th, 2014, 12:30 PM
What the advert failed to mention was what happened when you tried to read that disk six months later.
I own a punching apparatus not for practical use but rather as a museum piece.
I had a long term positive experience with those. i understand i shouldn't have had such good luck, but i did.
in 1992 i bought 100 used disks for a few dollars and converted all of them. i used the floppies for for 8 years or longer.
i never bought 3.5" floppies again after that.

Stone
April 7th, 2014, 12:34 PM
It's nuggets like this that I'm glad I subscribe to this forum.

I'm curious what you thought of the 3.5" "HD hole" punching machines to "double your diskette capacity for free!". (Joking -- I know what you think of them.) One of the advertising blurbs at the time was "We wrote and read the diskette continuously for 30 days without a single byte of lost data!"... What the advert failed to mention was what happened when you tried to read that disk six months later.

I own a punching apparatus not for practical use but rather as a museum piece.I couldn't agree with you less!

I just pulled 25 disks that I punched, formatted and then wrote to between 1988 and 1994. They all read and tested perfectly. That's 20 to 25 years of storage without any data loss. That kinda puts your 'six months later' statment in question, doesn't it? I understand that not everyone and not every media will realize this type of success rate with this particular issue but even some HD media will fail within six months without needing to have a hole punched to double it's existing storage capacity.

Chuck(G)
April 7th, 2014, 02:04 PM
Well, when DSHD floppies were $50 (1984 dollars) per box of 10, I did resort to stacking up a bunch of 2Ds on my drill press table and drilling a 1/8" hole right through the stack. They worked for a time, but one by one, started failing. I don't think I have a single one from that time. Of course, I don't have a single one of the $50/box floppies either.

One thing that interests me is the use of HD media in ED mode. Again, new ED disks were expensive and some folks claimed that they could format up HDs to 2.88M and they worked just fine. Unlike the DD-HD case, ED media is quite different from HD media--for one, the coating is usually barium ferrite, not iron oxide.

Does anyone have any surviving HD floppies recorded in ED mode?

offensive_Jerk
April 7th, 2014, 06:39 PM
Well, when DSHD floppies were $50 (1984 dollars) per box of 10
$50 in 1984 has the same purchasing power as $117.06 in 2014.
Each disk was almost $12 (2014 dollars)!

How did anyone afford computer stuff in the 80's?

lowen
April 7th, 2014, 07:33 PM
It wasn't easy.

I remember as a high school student in 1983 buying a plastic flip-pack of two Maxell DSDD 5.25 diskettes for $10 or so, and that $10 was pretty hard to come by. Those diskettes, formatted with TRS-80 Model III TRSDOS 1.3, still read fine, too, with my catweasel. Some CDC diskettes bought at the same time (for just as much money, too!) shed oxide and end up looking like a CD that's gone through the microwave for 30 seconds on high power. And the older Tandy/Radio Shack media has lasted well, too. You can even look at the old RS catalogs of the day at http://www.radioshackcatalogs.com/ ; a three-pack in 1983 would cost you $13.95, for TRS-80 branded single-sided certified media.

As far as formats go, PC's and Clones have it easy; there aren't that many. When you get to other systems the formats get more esoteric rather quickly.

What's always been a stumbling stone, in the non-PC world at least, is the 'density' moniker to distinguish between FM and MFM encoding; 'High Density' is MFM recorded at double the bit rate (and on the 5.25 at 360RPM versus DD's 300RPM); 'Quad Density' like used in the Tandy/TRS-80 2000's drives was DSDD 80 track for 720K (and I know the T2K isn't a 'PC Clone' but it is an MS-DOS machine nonetheless).

The DEC RX50 is fun, and those disks, as I recall, did not have hub rings, but the dual RX50 drive, again, as I recall, was pretty good about properly clamping and centering the cookie in the sleeve and drive. Those disks also have a bit of an odd format, and with the DEC Rainbow that could run its own MS-DOS on the RX50, that is somewhat on-topic.... just make sure you remember to put the bottom diskette in bottom-side-up!

And as far is 'cheaping out' on disks is concerned, I have more than a couple of flippies that are still readable. If you're not familiar with that term, that's using both sides of a diskette in single sided drives by cutting another index hole and write enable hole in the sleeve, and flipping the diskette over to use the top side. If done with real double-sided media it worked fine every time I tried it. The drives on the TRS-80 were single-sided anyway, and it saved money to use the otherwise unusable side. There are some 'dangers' we were all warned about back in the day, but with DS media I never had a problem with sleeve 'grain' or any of the other maladies everyone feared.

Of course, IBM shipped the TM100-2 double-sided drive (or equivalents) and flippies never really caught on in clone-space like they did in C64 world, Apple universe, and Tandy land.

krebizfan
April 7th, 2014, 07:36 PM
$50 in 1984 has the same purchasing power as $117.06 in 2014.
Each disk was almost $12 (2014 dollars)!

How did anyone afford computer stuff in the 80's?

Buy cassette tapes. Cheap, cheap, cheap. That covered the home market.

It didn't take long for floppy diskettes to drop in price as production increased. Just was not prudent to be an early adopter of new high capacity disks, made that much worse with all the teething problems initial production models had.

Remember how small documents were before graphics became common. A box of floppies could cover years of work for one person. Storage capacities increase, price per megabyte declines, and systems need more storage for better looking documents; the net result is the preferred amount of storage has kept about the same cost over the past 30 years.

MikeS
April 7th, 2014, 08:19 PM
...It didn't take long for floppy diskettes to drop in price as production increased.AOL probably did more than anybody to bring diskette (and CD) prices down, not to mention a free source of diskettes for the rest of us.
Interesting tidbits from http://techcrunch.com/2010/12/28/aol-floppy-disk/

...the first large mailing program began in the Spring/Summer of 1993, with about 200,000 discs (technically, still 3.5-inch floppy disks at the time) and other non-disk mailing being sent out at that time.
...
Incredibly, each floppy disk cost AOL $1.19 to make at first. And that’s just for the disk.
...
A few years ago, CrunchGear noted an AOL 1.0 disk selling for $5,000 on eBay.

DDS
April 16th, 2014, 06:42 AM
No one else has mentioned it yet so I will. There are incompatibilities between the write field strength and track width on 360k (48 tpi) and 1.2m (96 tpi) drives.

This is explained in detail here: http://www.retrotechnology.com/herbs_stuff/drive.html#thin

The worst case scenario in my experience is when you write a high strength half width 1.2m track right down the middle of a low strength 360k track. Neither drive will be able to reliably do anything with that track ever again until you throw the disk away in disgust or bulk erase it.

Back in my Heathkit H89 days I had a rig that allowed me to add the hub rings to disks that didn't come with them. The presence or absence of the hub ring doesn't really tell you much about the disk itself or how it was formatted (if at all) at the factory. I too have one of the punches that allowed you to make 1.44m disks out of 720k disks. some of them wouldn't work right off the bat, some are still good after 20 years. I also have had 1.44m disks bought bulk at the big box stores that curiously all had the same "random" volume number assigned when they were "formatted" somewhere in China. Those disks weren't worth a tinkers damn brand new out of the box.

Chuck(G)
April 16th, 2014, 08:35 AM
No one else has mentioned it yet so I will. There are incompatibilities between the write field strength and track width on 360k (48 tpi) and 1.2m (96 tpi) drives.

This is explained in detail here: http://www.retrotechnology.com/herbs_stuff/drive.html#thin

I think it's been mentioned repeatedly, just not on this thread specifically in those terms.

Not all 96 tpi drives are "1.2M", nor all "1.2M" drives capable of 360K to further muddle matters.

MikeS
April 16th, 2014, 01:32 PM
No one else has mentioned it yet so I will. There are incompatibilities between the write field strength and track width on 360k (48 tpi) and 1.2m (96 tpi) drives.Actually, I thought Mike's link in post #10 mentioned and explained it quite clearly:

Double density 5.25" drives use 40 tracks per side. When high density 5.25" drives were introduced, they doubled the number of tracks to 80 per side. To do this, a narrower disk drive head had to be used.

A high density 5.25" drive can read a low density diskette just fine, even though the drive head is narrow compared to the track. However, if you try to write to the diskette, you will write a new track of data that is much narrower than the existing data. This will generally make the diskette unreadable in a double density drive, because the double density drive has the old "fat" drive head that will see a narrow data track laid on top of a normal sized data track.

Other high density drives may not deal with this diskette well either, depending on their calibration.

If using a double density 5.25" disk in a high density drive, only do reads from it - make sure that you do not write to it!

As to
Neither drive will be able to reliably do anything with that track ever again until you throw the disk away in disgust or bulk erase it.Bulk erasing is certainly preferred, but most of the time an HD drive will be able to read an HD track on top of a DD track (there are erased guard bands on both sides of a track), and reformatting on a DD drive (several times if necessary) will often make the disk usable again.

vwestlife
April 16th, 2014, 02:37 PM
In my experience, newer half-height 360K drives have much less problem exchanging data back and forth with 1.2MB drives on 360K disks than the old full-height drives. Maybe once high-density drives became common they started using narrower heads on 360K drives as well.

MikeS
April 16th, 2014, 02:50 PM
In my experience, newer half-height 360K drives have much less problem exchanging data back and forth with 1.2MB drives on 360K disks than the old full-height drives. Maybe once high-density drives became common they started using narrower heads on 360K drives as well.I don't know that the heads are any narrower but with more modern manufacturing and QA procedures they are probably more precise; also, track positioning is probably more accurate and repeatable.

Chuck(G)
April 16th, 2014, 04:02 PM
Somewhere, kicking around in my old stuff, I have a driver that will record a second 360K image on a DSDD disk written in an HD drive. It just uses the odd-numbered tracks, where the "360K" normal format uses the even ones. I used to snag forensics trainees with that one back in the day. They'd try something like Norton on the disk and not find the evidence...

Stone
April 16th, 2014, 04:17 PM
Would you kindly dig that one out so we can have a go at it?

Chuck(G)
April 16th, 2014, 05:56 PM
I'll dig around. BTW, I did find another that creates a 160K phantom DOS drive on a 1.44M floppy. Nowadays, that 160K would be utterly invisible if read on a standard 1.44M USB floppy.

If you have a Catweasel, I have another than hides data in the inter-sector gaps.

Shadow Lord
April 16th, 2014, 10:36 PM
Well after going through this thread I did a quick search for FormatQM and there is a full version for sale on fleecebay for the low low sale price of $90 + S&H... I guess I'll have to dig up a SW version just to see it in action at least!

Chuck(G)
April 17th, 2014, 08:25 AM
$90? :shock: I think we offered registration for it for $10. There's not much difference between the share/registered versions, anyway.

Shadow Lord
April 17th, 2014, 08:34 AM
$90? :shock: I think we offered registration for it for $10. There's not much difference between the share/registered versions, anyway.


Yes you did according to the readme. He also has a copy of CopyQM for the same price.