back to article Longstanding bug in Linux kernel floppy handling fixed

Linux kernel 6.2 should contain fixes for some problems handling floppy disks, a move which shows that someone somewhere is still using them. This isn't the only such fix in recent years. As a series of articles on Phoronix details, there has been a slow but steady flow of fixes for the kernel's handling of floppy drives since …

  1. A Non e-mouse Silver badge

    I doubt the larger floppy formats would have delayed the rise of the writeable CDs & DVDs. The capacity they offered was far greater than anything the floppy drive ever offered.

    1. Anonymous Coward
      Anonymous Coward

      > The capacity they offered was far greater than anything the floppy drive ever offered.

      And durability also (for good quality CDs).

    2. sarusa Silver badge
      Thumb Up

      They were all proprietary too. SuperDisk, Zip drive, anything from Sony. The beauty of the plain old 5 1/4" and 3 1/2" floppy disks was that anyone could make the disks or the drives, and they did.

      1. DrXym

        SuperDisk was neat technology but it was delayed too long into irrelevance. I thought it was cool though because the drives were backwards compatible - in theory you could buy a PC with a SuperDisk drive instead of a normal one and out of the box you got this extra storage capacity. It would also mean that the disks would be the same dimensions as regular disks which was handy for storing them.

        Didn't really matter by the time they appeared though because Zip disk had been out for years. I had a 100Mb zip drive and it worked fine too but it was kind of galling to have to run two devices where one could have served both roles.

        1. doublelayer Silver badge

          "It would also mean that the disks would be the same dimensions as regular disks which was handy for storing them."

          I really hope they were still easily distinguished, because otherwise that sounds like a recipe for getting confused why this floppy doesn't work in that older standard-only drive. It reminds me of a time when someone mixed a stack of blank CDs with some ones that had been written to, requiring me to insert each one to find the ones with actual data on them. Although I arrived too late to prevent that, I did get there in time to prevent them mixing in the blank DVDs too.

          1. Liam Proven (Written by Reg staff) Silver badge

            [Author here]

            > I really hope they were still easily distinguished

            SuperDisks from DSHD? Very easily: the HD disk's shutter was rectangular, and slid; the Superdisk's was triangular, and it pivoted.

            DSHD from DSDD: double density had 1 write-protect hole, with a sliding cover; HD had a 2nd hole in the other corner on that edge, with no cover.

            SSDD from DSDD: nope. Format it and hope for the best.

      2. Hans Neeson-Bumpsadese Silver badge

        The beauty of the plain old 5 1/4" and 3 1/2" floppy disks was that anyone could make the disks or the drives, and they did.

        I think that another attractive feature might have been the fact that blank floppy disks in the company stationery cupboard fit neatly in a pocket and work exactly the same as the ones available in the shops for personal use

    3. DrXym

      I never even heard of these 2.88Mb floppies and they certainly weren't mainstream. People who wanted more storage would buy an Iomega Zip drive or similar.

      Once CDROM drives turned up there was little reason for floppy disks except for installing drivers or boot disks. And even Iomega Zip drives became irrelevant as things like rewritable media and USB sticks turned up.

      1. Liam Proven (Written by Reg staff) Silver badge

        [Author here]

        > People who wanted more storage would buy an Iomega Zip drive or similar.

        2.8MB floppies appeared in about 1990.

        Zip disks appeared in 1994.

        Around that time, the industry was moving much faster than this century. That was a *long* time.

        1. jake Silver badge

          "Around that time, the industry was moving much faster than this century. That was a *long* time."

          Coincidentally, I was just looking at receipts from a long-time client of mine.

          In January of 1990, he paid $1199 for a 40 Meg Western Digital HDD (with a one year warranty). In November of 1994, he paid $849 for a 1 Gig Seagate (five year warranty). That's roughly a drop from $36/meg to 85¢/meg.

          The price of RAM lagged HHDs ... In 1990, RAM was about a hundred bucks per meg. By ~'92 it was hovering between $92 and $95 per meg, where it stayed until about 1997 when the price started to plummet. By '98 or so you could get SIMMs for about $5/meg.

          People who weren't in the industry as adults during the late '80s and early-mid '90s have no clue how fast things were moving.

          1. keithpeter Silver badge

            Somewhere on that time line were Syquest removable hard drives. Mainly a Macintosh thing I believe. Designers toddled about with Photoshop and a pile of work on their Syquests and went from Mac to Mac.

            Zipslack (a small Slackware that you copied to a Zip drive) was a learning experience (back on generic Pentium hardware)

            Icon: ancient history

  2. Nate Amsden

    1.9MB floppies

    I remember some app back then allowed you to format a regular 1.44MB (which I think was otherwise 2MB unformatted) floppy into a usable ~1.9MB disk, and I think it was done in a standard way no special software needed to read it.

    I remember being excited to buy the retail version of win95, after having used pirated betas for a while. Bought from Fry's Electronics (RIP), wasn't paying attention since it wasn't until I got home I realized I bought the floppy version. Ugh. Then I made that same mistake again with OS/2 Warp, though I remember OS/2 being far worse(more disks? slower access?), or maybe that memory was incorrect. Also the OS/2 Warp addon that gave internet support? I didn't use it long just played with it, and multi booted with system commander(?).

    Last time I think I was in a situation that required floppy disks was in 2009, needed to update the firmware on many Seagate drives on several older Dell rackmount systems, and the only way to do it was a DOS floppy. Fortunately I wasn't the one that had to go connect a USB floppy to each system and boot/update them but I did figure out what the issue was(after the company struggled to find a solution before I was hired for a year). It was the first time in my career where I needed to update the firmware of a disk drive.

    1. MacroRodent

      Floppies against the passing of time

      I last used 5 1/4" floppies in anger in 2017 to rescue the electronic forms of my grandmother's and some of her ancestors' memoirs. She had not entered the texts, one of my uncles had done them in the 90's when preparing a self-published book in WordPerfect. Despite the passing of the time, no problems in reading them, except I had to resuscitate an old PC to do it. LibreOffice then interpreted the WordPerfect files nicely. The 360k floppy appears to be fairly robust against aging, if stored decently. Of course it is not so durable mechanically. This floppy had probably been written and read only a few times, and then left alone for years.

      1. Paul Crawford Silver badge

        Re: Floppies against the passing of time

        My father has a Sharp "word processor" which was basically an electric typewriter but you could preview the text before it started hammering the paper, and save it to floppy. Eventually it died and he desperately wanted access to the saved files which, to be fair to him, he generally had saved two copies on different disks.

        Unfortunately the floppies were oddly formatted, sort of MS-DOS but not quite, and any windows machines saw them as corrupt/unformatted so wanted to format them and so trash the data. Also the file format was something peculiar to Sharp and they did not have any information on it (presumably long lost code).

        I was able to make an image of the floppy disks using Linux and the 'dd' utility, then I could mount a copy of that image as a virtual floppy on a VMware machine running DOS 6.22 that could chkdsk them without damage and so render the files readable without cross-links, and then copy all of the files off. All dated Jan 1980 as the typewriter had no clock, of course.

        Finally I was able to write a small C utility that would extract the test from the odd .doc files and translate some of the special characters such as 1/2 or 3/4 into Unicode, etc, and render a version that could be printed on a modern computer in a manner that was tolerably close to the paper copies of some letter he had that I used to reverse-engineer the formatting of the files.

        1. Mowserx

          Re: Floppies against the passing of time

          Quite impressive!

    2. anothercynic Silver badge

      Re: 1.9MB floppies

      I remember being given the 28 (?) disk version of OS/2 Warp to install... it failed because my laptop for some reason had a SCSI interface built in, which couldn't be disabled, and which OS/2 Warp tried to configure and failed. I still have that box here somewhere...

      1. bouvin

        Re: 1.9MB floppies

        > I remember being given the 28 (?) disk version of OS/2 Warp to install... it failed because my laptop for some reason had a SCSI interface built in, which couldn't be disabled, and which OS/2 Warp tried to configure and failed. I still have that box here somewhere...

        As I recall, IBM was quite free with giving out the OS/2 Warp install kits, which was great as a student, as blank floppies were expensive.

        1. vtcodger Silver badge

          Re: 1.9MB floppies

          "as blank floppies were expensive."

          Not in the US. Most of us got by reformatting the free floppies that AOL sent us (it seemed) every 3 or 4 weeks to try and get us to sign up. But yeah, 28 free floppy disks would be a windfall.

        2. Benegesserict Cumbersomberbatch Silver badge

          Re: 1.9MB floppies

          All but the boot disk were the 1.68MB XDF format which took more than twice as long to read each track, something to do with having interleaved sectors.

          You could reformat them, if you were lucky.

    3. spuck

      Re: 1.9MB floppies

      Microsoft also distributed software on 3.5" disks (see which gave them ~1.6MB on a 1.44MB disk by adding a few sectors per track, as well as limiting how many sectors the FAT12 tables took up.

      I don't remember how many floppies Win95 came on, but I guess if you could squeeze it down enough to save even 1 disk per copy, that adds up.

      Every byte counts when you're buying them by the cargo container.

      1. Anonymous Coward
        Anonymous Coward

        Re: 1.9MB floppies

        > Every byte counts when you're buying them by the cargo container.

        You were buying them in the docks, too? You could get a lot of cheap stuff there back in the day.

    4. usbac Silver badge

      Re: 1.9MB floppies

      I last used floppy disk (5 1/4) to boot my original Apple ][ about two years ago. I was selling it off on ebay, and wanted to make sure it worked okay. I had a couple of original Apple DOS disks dated 1979 on the label. They still booted just fine (I cleaned the drive very well before trying it). The old Apple powered up and worked totally fine. I even had an old Commodore color CRT monitor for it that originally came with a Commodore 64.

      Someone paid what I would consider a ridicules price for the thing on ebay. They were happy to get it, and I was happy to have the space back in the garage (and the cash too).

    5. DrXym

      Re: 1.9MB floppies

      OS/2 used a weird format for its boot disks that stored more than 1.44Mb on a floppy. Not sure what they did to achieve this but it did mean less disks to insert when installing the thing. After installation though, it was just a regular floppy disk drive with FAT formatted disks. Can't remember if OS/2 supported FAT32 info or not.

      1. milliemoo83

        Re: 1.9MB floppies

        "OS/2 used a weird format for its boot disks that stored more than 1.44Mb on a floppy. Not sure what they did to achieve this but it did mean less disks to insert when installing the thing. After installation though, it was just a regular floppy disk drive with FAT formatted disks. Can't remember if OS/2 supported FAT32 info or not."

        1.8MB XDF. Along the lines of M$'s 1.7MB DMF.

    6. Stork

      Re: 1.9MB floppies

      Last I used a floppy was in 1999, the inside as a filter to observe the solar eclipse.

    7. Michael Wojcik Silver badge

      Re: 1.9MB floppies

      the OS/2 Warp addon that gave internet support?

      I think you misremember. IIRC (and Wikipedia appears to confirm this, for what that's worth), OS/2 Warp included TCP/IP. Warp Connect added LAN Manager / NetBIOS / SMB / DLC / etc. support. Warp 4 had all of that built in, plus Java and speech recognition.

    8. Ignazio

      Re: 1.9MB floppies

      If memory serves, double sided high density floppies could be formatted with 21 sectors, and some floppy drives - not all - could stick two tracks extra on the disk. Win95 floppies contained a single file that was larger than 1.44 megabytes and used that formatting scheme.

      (Yeah I bought it, on purpose - my computer didn't have a CD drive at the time. Box of floppies still somewhere in a cupboard. Not sure if any of the computers that are still operational in the same cupboard actually have a motherboard slot to plug in a floppy drive ribbon)

  3. Alan J. Wylie
    1. David 132 Silver badge

      Re: Boeing use(d) them

      Yes. I'm sure that if the remaining user(s) of floppy disks with Linux are ever identified, they'll turn out to be needing them for an embedded industrial application of some sort. CNC lathes, aerospace, or whatever. I highly doubt that there's any general-purpose home/office PC users still reliant on them... surely?

      1. An_Old_Dog Silver badge

        DIAGNOSING Embedded Industrial Systems

        is a process using bootable Linux floppies. tomsrtbt jumps to mind. So does that bootable floppy diskette which chain-boots CDs ('cause the older systems' BIOSes aren't designed to boot from CD).

        1. Citizen99

          Re: DIAGNOSING Embedded Industrial Systems

          tomsrtbt Brlliant, I have it migrated to later media. Before retirement 20yrs ago,we got a loaned Linux PC back from a contractor. Used tomsrtbt to smash their root passed and bingo we have control.

      2. heyrick Silver badge

        Re: Boeing use(d) them

        With older machines that don't have Bluetooth, or have weird networking setups (or, shudder, a lone BNC socket for that), sometimes dumping files onto a bog standard 1.44MB floppy is the least annoying way of getting stuff from one machine to another.

        There's probably no excuse or reason for floppies if none of your hardware predates Game of Thrones, but if you have stuff from the '90s then they can be useful.

      3. Martin Gregorie

        Re: Boeing use(d) them

        I'm certain you're right that embedded industrial applications ARE still running productively on kit that used to boot its firmware off floppies.

        That's why hardware devices like Gotek units are still being manufactured and sold. These are hardware devices built to the same form factor and using the same connectors as 5.25" and 3.5" floppy drives and were designed from the outset to be replacements for the original drives. They provide legacy equipment with access to floppy disk images recorded on SD cards and/or USB sticks.

        I've not used one myself, but I know that, apart from those keeping older computer-controlled tools in productive use, another gang using them is the 8-bit computer enthusiasts, who are more numerous than you may realize, and who use them, both as replacements as their 3.5 and 5.25 floppy drives die, but also as a hedge against the increasing deterioration of their original floppy disks: the Gotek also provides a convenient way to store and copy disk images when the original floppies and drives have died.

        1. F. Frederick Skitty Silver badge

          Re: Boeing use(d) them

          Gotek and HxC drives are popular with musicians as well. A lot of highly sought after gear such as synths, samplers and sequencers use floppy drives for storage.

          If recent Linux kernels disable raw device access, then that's a pain though. These machines often have proprietary disk formats and need to be read by specialised software to image them.

          1. ChrisC Silver badge

            Re: Boeing use(d) them

            TBH, despite being a somewhat active member of the retro computing scene, I'd never heard about this feature of Linux - whenever people talk about wanting to grab a raw disk image, it's in reference to one of the various bits of custom hardware built for this purpose, e.g. Kryoflux. So I suspect there's something in the Linux implementation which leaves it a bit lacking compared with the hardware solutions.

            Anyway, I guess my point here is that, even if Linux does lose this ability forever, it won't mean that the ability to image old proprietary/copy protected/damaged/etc disks will be out of reach of the average enthusiast and left to professional data recovery places - these bits of custom hardware aren't prohibitively expensive to buy in their ready-made forms, and IIRC there was at least one where the design was open-sourced so you could build the hardware yourself out of a STM32 devboard and some anciliiary components.

      4. jake Silver badge

        Re: Boeing use(d) them

        I do an annual cleaning & adjusting (if needed) of a couple of 8" floppy drives that have been in near daily use since the late 1970s. They are attached to a couple pieces of equipment at a machine shop located in SillyConValley. I've replaced the read/write heads, the motors and other parts[0] a couple times each with NOS[1] parts that I squirreled away in the '90s .... sometimes being a packrat helps pay the bills.

        Granted, they aren't running Linux.

        [0] We started calling them "Theseus's Floppy Drives about two decades ago ...

        [1] New Old Stock ... brand new original box product that's been on the shelf for a while.

        1. Anonymous Coward
          Anonymous Coward

          Re: Boeing use(d) them

          In the late 1990's, I went to the London Science Museum and saw a set of 8" floppies there. A week or so later, a customer sent in identical drives to be fixed! Fortunately, my colleague had to deal with it!

          1. dr john

            Re: Boeing use(d) them

            A friend of mine in the late 80s early 90s had a job servicing 8" floppy drives in building societies which used ancient computers. The cost of getting their custom software re-writen and tested to work on a PC was so great and so risky, they had to keep the drives working for a very long time. He as regularly driving a couple of 100 miles every day to rescue these drives.

    2. An_Old_Dog Silver badge

      Boeing Uses Floppy Discs

      The last 747 rolled off the line, but it, and all the other 747s in service, will still need software updates.

    3. Cliffwilliams44 Silver badge

      Re: Boeing use(d) them

      It took NORAD (the nuclear missile folks here in the US) until 2019 to upgrade their systems to no longer use 5 1/4 floppies in thier launch control systems. What pushed them to upgrade was all the guys who knew how to maintain these system were in their 60's.

  4. Scoured Frisbee

    I used them in mid-2010s at a prior employer, we had an oscilloscope that would only store images to 3.5" floppy. It was oldish but sufficient for that company's occasional needs, and sufficiently expensive that there wasn't will to upgrade, so it's probably still in use barring a catastrophic failure.

    1. BenDwire Silver badge

      I bought one of those too, a Tektronix if memory serves. We even managed to get trace printouts by using an odd Epson laser printer in some strange compatibility mode.

      'Scopes used to cost a fortune compared to the cheap Chinese devices we can buy now. But then again I used to have a 1960's Cossor scope in my bedroom as a kid, so I'm more than a bit weird.

  5. Anonymous Coward
    Anonymous Coward

    Compaq Softpaqs

    The last reason I ever found myself scrabbling round for a floppy drive connected to a PC.

  6. amacater

    tomsrtbt 1.722M on a 1.4M floppy ... probably the most useful thing since sliced bread.

    1. Citizen99

      Also migrated to later media; use case on earlier thread response

  7. Missing Semicolon Silver badge

    Looks like I'll not be updating then

    .. if they've disabled raw access to the controller.

    I have an old Core2Duo box, which I think is the last motherboard new enough to support modern 64-bit linux, but old enough to have a floppy interface. I keep it for data recovery from old floppies.

    1. Dan 55 Silver badge

      Re: Looks like I'll not be updating then

      You can compile a kernel with CONFIG_BLK_DEV_FD_RAWCMD in the meantime, before they remove it sometime in the future.

      Rather disappointing that they've decided to clobber the option instead of fixing the race condition.

    2. jake Silver badge

      Re: Looks like I'll not be updating then

      If you just need it to recover data from old floppies, Shirley running Linux 2.6.x would suffice? Or even 2.0.x, for that matter. Not sure why 64bit would make a difference one way or the other.

    3. Liam Proven (Written by Reg staff) Silver badge

      Re: Looks like I'll not be updating then

      [Author here]

      > the last motherboard new enough to support modern 64-bit linux, but old enough to have a floppy interface.

      I have such a box, too. Two in fact. The snag is that the last era of PC motherboards with floppy interfaces only supported 1 drive. I had a few of them. You can connect 2 floppies, that's easy -- they used the same port and just a 3-ended cable -- but you can only use drive #1. I suppose the cheaper FDC chip saved money.

      The problem was I wanted to get data back from both 3½" and 5¼" floppies. That meant 2 PCs. Very annoying cost-cutting measure, for me.

  8. werdsmith Silver badge

    I can’t remember the last time I used a floppy but I found a sealed box of them (5 1/4) in a data centre about 3 years ago.

    I can remember having a feeling of being a bit uncomfortable when I first got a PC that didn’t have a floppy drive.

    I think I still have a Cd/DVD drive on a usb cable in a drawer somewhere.

    1. Tom Womack

      I bought a new USB CD/DVD drive last Christmas, because I wanted to rip my Christmas CDs and my Mac Mini M1, whilst wonderful in almost all ways, lacks an optical drive. For as long as media is distributed on shiny discs, people will want to watch the shiny discs on computers ...

      1. doublelayer Silver badge

        They'll keep making those external drives for a while, I'm sure. I value not having to carry it around or integrated into every machine, though. While they still make laptops with optical drives, every model ends up being a lot bigger and heavier than one that ditches it. I don't use the media enough that going to my closet and retrieving the USB one is a problem.

    2. Ace2 Silver badge

      I buy $1 DVDs at the thrift store and then rip them with an external DVD drive and Handbrake. It works great and is cheaper than any streaming service.

      1. Grunchy Silver badge

        My library still loans out CDs and DVDs, for nothing! Most are still readable.

        (I save up my $1s and use them to buy "Certs" candy instead!)

  9. Number6

    I still have a machine with floppy drives on it. I don't remember where I picked up the drive unit, but it's a single half-height 5.25" form factor and has both a 5.25" 1.2M and a 3.5" 1.44MB floppy in it. As far as I know it still works, although I've not inserted a 3D model of a save icon in there for some time. There's probably a 3.5" USB drive somewhere on the shelf too, as well as a Zip drive.

    For good measure I have a BBC Micro B (modified a bit) with dual floppies, although probably no original media to use with them.

    1. Grunchy Silver badge

      That dual-drive is a TEAC FD-505, they are desirable. Though you are right, hardly none of them work anymore. Well, they need new belts, you see.

  10. Dante Alighieri


    1.6MB floppies with ADFS, yes supported in linux. Not so sure about my custom MO-Drive (640MB) acorn formatted discs, possibly unique on the planet...

    And a few MO discs from many US machines where they were core transfer media

  11. Retrograde

    Sometimes use floppies

    I think it's a cool idea if Linux still supports them as long as the code to patch the drivers isn't delaying more pertinent and modern features that most people use. For a retro tech enthusiast like myself and many others it could be handy to keep in the toolbox. Who knows.

  12. Crypto Monad Silver badge

    Virtual machines

    I've seen plenty of VM setups where virtual floppy disks are used to attach configuration data. As long as less than 1.44MB or 2.88MB of data is required, "floppies" may live on this way for years to come.

  13. Screwed


    Thank goodness ZIP drives didn't become standard. At least, not while they were still affected by click of death. Did that ever get fixed?

    And remembering processor usage they could achieve. (SCSI ones were much better.)

    1. Sandtitz Silver badge

      Re: ZIP

      "Thank goodness ZIP drives didn't become standard. At least, not while they were still affected by click of death. Did that ever get fixed?"

      Some had the click of death. My parallel port ZIP100 from circa '96 worked well for uh... the 5 years I used it for and the Zip floppies were very durable as well, never had a single failure.

      The parallel port drive was the slowest model, yet it was perhaps 10 times faster than normal floppy drives. It was also quite portable (apart from the power brick) and every PC had a parallel port.

    2. Henry Wertz 1 Gold badge

      Re: ZIP

      Yeah. The parallel port zip my parents had was immune to the problem, and the early production run was in general (along with later production, presumably.). At some point during production, for a few months they decided to try (if I recall correctly) conductive glue on the read/write heads instead of solder; the glue didn't do the trick, the head would come unglued. The click was just the same "lets try whacking the head around to 'recalibrate' it" kind of thing hard drives do when they hit bad sectors, this of course was not going to help when your read head has fallen off. It became contagious, apparently the read head would just straight up fall into the Zip disk sometimes and it'd tear up the next zip drive you put it into. My parents missed out on that since they weren't exchanging Zip disks with anyone.

      Amusingly, it acutally is a SCSI Zip drive with a parallel to SCSI adapter on it, I recall firing it up in Linux. "Bit banging" the paralell port at 100s of KB/sec really hoses your system response but with the 400MB or so HDDs of the time having an extra 100MB at at tiime on disks was pretty nice.

  14. Potemkine! Silver badge

    Good news everyone!

    Works every time

    == Bring us Dabbsy back! ==

  15. Anonymous Coward
    Anonymous Coward

    The odd thing is that they've survived so long despite not evolving.

    Unless they've kinda reached "perfection".

    A wander through most museums will reveal tools that are instantly recognisable despite being 2000+ years old. They simply cannot be improved on.

    Something the current crop of i-whatever fans need to remember.

  16. Grunchy Silver badge

    Yup, I still run the 3.5" floppy disk. I got my TEAC 27L4226 USB portable drive specifically to read old 1.44MB diskettes (most of my collection were still readable!)

    When I was about 12 I bought my first storage media, a 3-pack of 5.25" diskettes from Radio Shack for $20 that held 360kb each for a combined total of over 1 MB! When a 20MB hard disk could cost thousands of dollars, and here any kid with $20 could buy convenient, interchangeable media of about the same order in size. I paid $20 for the TEAC drive (new) and don't think it's worth any more, though there are lots of people begging as much as $45. Just scrounge harder. Lately I splurged $40 for a 512GB SanDisk "Ultra Fit" USB 3.1 flash device which is about the size of a "Certs" candy. I'm aware of certain CNC tools that can still load G-Code from floppy but come on, modernization is cheap & easy. All of my 3d printers utilize SD card media.

  17. the spectacularly refined chap

    From the article:

    Normally you don't need that to read and write to diskettes: it's only for things like handling floppies with formats other than the basic PC- and Mac- 1.4MB "high-density" format, or handling copy-protected disks, and so on. This sort of stuff won't work if you use a USB floppy drive, anyway: their embedded controllers only understand standard formats, and so can't handle classic Mac or Amiga double-density disks from the 1980s.

    That's actually conflating two slightly different issues. The PC style high capacity formats such as DMF and XDF generally either crammed more sectors on a track or used a higher than normal number of tracks.

    The former reduced the inter-sector spacing demanding higher tolerance in speeds and timings, and so was only really suited for single pass format-and-copy use such as software distribution. They were decidedly "dodgy" for general purpose use especially between machines, any slight mistiming could cause the end of one sector to overwrite the start of the next.

    The extra tracks were of a "this is out of spec but works on most drives and disks" thing, relying on the fact most drive heads could physically seek slightly past the track 40 or 80 position and most disks still had usable media for another couple of tracks. Fine, until you encountered a drive or a disk where those assumptions didn't hold.

    The Mac and Atari high cap formats worked differently: those used additional sectors per track but only on the outer (longer) tracks. Timing and spacing were preserved by physically spinning the disk slower when accessing those outer tracks. It is not a question of software or even firmware - a standard PC floppy drive is mechanically incapable of altering speed to read those disks.

  18. Tiago

    Big Box PC Gamer Here!

    Don't be so surprised!

    A lot of people still uses floppies, I know that some military and old airplanes uses them.

    But in my case is more fun than work. I collect big box pc games, and most of them are indeed in floppies (even 5'4" ones) and I use an USB floppy drive on my modern PC, although I also have some old machines laying around.

    Almost every week I'm reading floppies and even burning floppy images on fresh diskettes.

    That's awesome that we'll got fixes!

  19. david1024

    I still use them!

    Have a portable pre-wifi oscilloscope that stores data on them.

  20. Holobob

    Japan still uses them, the government has just started a campaign to get rid of them in government departments. I've been to one of our local hardware shops in Japan, and they still sell floppies, minidisks, blank CD's and fax machines, so someone must be buying them....

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