Originally Web posted Tuesday, 13 May 2008.
Content last modified Wednesday, 29 June 2016 .
External links last verified Wednesday, 29 June 2016.
As time passes and floppy disks become relics of computing’s past (especially in the Macintosh world), folks seem to be confronting more problems accessing information stored on this older format. This page attempts to address methods and workarounds for accessing data on Macintosh floppy disks (using Apple Macintosh and clone hardware) and moving the desired data to newer Mac systems.
“Hey! I’ve got a floppy drive on my Mac, and it reads some floppies just fine, yet not others. What’s the deal?”
Depends. Below are the most common scenarios:
As is well documented, modern Macs from this millennium (and some before) no longer come with built-in floppy drives. The available option is a 3rd. party external floppy drive. All the ones i have seen connect via USB.
What is Not well-known is that these drives, being more generic, lack a crucial feature of Apple-specific floppy drives: Variable Speed. You may have noticed (or not) that long ago, when floppies were common, the original 3.5" single-side double-density (SSDD or for our purposes SS) hard-case floppies held something like 270k or 360k on PC-compatible computers (if they even used those… i didn’t and don’t know) while the same floppy formatted and used on a Mac held 400k. Similarly, double-side double-density (DSDD or for our purposes DS) 3.5" floppies hold 720k on a Wintel, and 800k on a Mac.
How did Apple do this? By using a variable-speed spindle drive system instead of fixed-speed, to cram more data on the same magnetic material space. That is why Mac floppy drives make sounds of different audible pitches as they move around the disk surface: the motor speed is changing!
As of the emergence of high-density (HD) floppies in the early 1990s, Apple was growing weary of being slammed around in the marketplace. One of many, many causes was the higher price of Macintosh computers. While there were many reasons for this, one was Apple’s penchant to innovate and improve upon the standards. As the Wintel juggernaut began to steamroll them, Apple sought ways to cut costs. It was a whole lot easier and more financially sane for Apple to go with the flow and use the same standards for 1.4 MB floppies as the Wintel world… economies of scale, dontcha know! This is all my conjecture, anyway. This is fact: With 1.4 MB HD floppies, Apple agreed that fixed-speed drive was what they would use.
Bottom line: a generic fixed-speed external USB floppy drive will work with 1.4 MB HD floppies, yet (to the best of my knowledge, and i may be wrong) not Mac 800k or 400k floppies. They’ll likely also read 720k DS floppies. My guess would be that they could read 360k SS floppies from other systems. (I don’t have/could not easily make a 360k floppy to test this theory.)
Unless you can find an external USB drive that specifically claims to support Mac 800k disks (i really doubt you will find one that supports 400k), you will almost certainly need to find an older Mac with a built-in floppy drive to access your data on DS and SS disks.
So ya say ya gotta Mac with a built-in SuperDrive that is allegedly able to handle 400k, 800k, and 1.4 MB disks, and it does work with 800k DS and 1.4 MB HD disks, yet not with 400k SS disks? Well, you need more than the drive… you need the correct Mac software.
Please look carefully at the two images just above this paragraph. They are two screenshots of the same floppy disk in the same drive of the same Mac, taken minutes apart. The difference? The Mac OS version running the machine. The “unreadable” picture was when OS 9.1 was in charge. The working, mounted disk Finder window—same disk, same conditions—was when the very same Mac was running OS 7.6.1.
You’re suffering from the MFS Blues! MFS, the original Macintosh File System, was a flat-file structure used on Macintosh computers from Day 1 until the era of the 128k ROMs and the Mac Plus, which is to say circa 1986. It had the illusion of folders, yet no actual directories. With the 128k ROMs, System 3, and all that came HFS: Hierarchical File System: folders that were actual directories and subdirectories.
For backwards compatibility yet moving the world forward, Apple decided that the Normal Order of Things would be that 400k floppies would be formatted as MFS when erased, and 800k and larger floppies as HFS. (There are tricks to circumvent these defaults… tricks i have not used and therefore not memorized. Folks who used these tricks could create 400k HFS floppies for sure, and maybe 800k MFS floppies.)
Thing is, on these early Mac OS versions which supported both MFS and HFS, there was no electro/mechanical way to detect DS from SS diskettes. Apple needed to count on the user to make the correct choice (screenshot is from System 3 running on a Mac Plus):
Clicking the One-Sided button formatted the disk as 400k MFS. Clicking the Two-Sided button formatted the disk as 800k HFS.
Many Mac users have found it tough to let go of their older Macs, especially early on when they were (relatively) very expensive pieces of equipment. A person might have several Macs, one or more of them original 128k or 512k non-Enhanced “Fat Macs” (Fat=more RAM in this case) with the original 64k ROMs which only understood MFS format. Sitting in front of their 512KE or newer Mac (with 128k or larger ROMs), they might very well want to format a double-sided diskette as single-sided, for use in their older Mac(s)—especially in the latter years of the 1980s and thereafter when SS/DD 3.5" floppies first became scarce then disappeared from the market. Thus, while rare, it may not be terribly unusual within a specific floppy disk collection to find disks marked DS/DD with 400k capacity and MFS formatting.
As well, floppy disks were expensive in the mid-late 1980s. Rumors circulated circa 1987 that due to lower demand for single-sided 400k diskettes, Sony merely ran the same production line for double-sided 800k and single-sided 400k, marking them differently and probably not QAing the second side for the ones being sold as single-sided. Someone found out that the less expensive Sony single-sided 3.5" diskettes sold new during this period more often than not formatted successfully as 800k double-sided. Older Sony single-sided disks and most single-sided disks from other manufacturers would behave as expected: they would fail to format as two-sided. A failure to format dialog would appear and the disk would be ejected, as in the case of defective diskettes attempting to be (re- or initially) formatted at any capacity.
Allowing (requiring) the user to select single- or double-sided when erasing (formatting) a floppy disk remained as shown above all the way through the end of System 7.1 (7.1 Update 3). System 7.5.0 through 7.5.5 allowed writing to as well as reading from MFS-formatted floppies, but did not allow erasing/formatting SS and DS disks as anything other than 800k double-sided HFS or ProDOS (Apple II format), or 720k DOS:
The screenshot is from OS 9.1, yet other than cosmetic alterations, it’s the same dialog all the way back to System 7.5 (7.5.0).
The upshot of all this is one cannot trust the marking on the diskette! Probably the single-side/double-side marking (when it even exists in the first place) will match reality, but don’t count on it!
This is how things worked and remained pretty compatible from something like System 3 up through the end of Mac OS 7 (7.6.1). With Mac OS 8.0, Apple eliminated OS support for MFS format. From the Apple Installing Mac OS 8 Read Me:
• 400K diskettes and Mac OS 8 The 400K MFS diskette format is not supported by Mac OS 8. If you have information or programs on obsolete 400K diskettes that you want to access, copy the files to your hard disk, an 800K diskette, or a 1.44 MB diskette before installing Mac OS 8.
So, OS 9 ain’t gonna cut it. Nor is OS 8. You need OS 7.6.1 or earlier to work with 400k MFS disks. Now, disk images are a whole other story!
Specifically, OS 7.6.1 will read MFS-formatted floppy disks, but it will not write to them, including erasing/reformatting them in their MFS form:
Notice the padlock icon in the “working” screenshot above. That disk was not locked, nor was the drive having any trouble sensing the disk’s lock slider. Apple was gently guiding people away from this very old, early format, allowing them to still read data on their MFS-formatted diskettes but not create new ones nor write to existing ones. Read, copy to newer media, recycle!
This presents an interesting dilemma for folks with Beige G3 and later Macs with built-in floppy drives: These Macs originally shipped with OS 8.0 or later, and are therefore unlikely to run with OS 7.6.1 or earlier without some serious hacking! And anything earlier won’t run any OS X without a healthy dose of XPostFacto hackery. Below i discuss some ways to handle this dilemma.
As i was researching updated/corrected information for this article on 29 June 2016, i encountered the mechanical/lubrication problem on a Mac IIsi. I had cleaned/lubed the machine’s internal floppy drive in 1999, but it had not been used much since then. When i first inserted two different floppies (400k MFS and 800k HFS, under Systems 7.0-7.5), the drive/OS/Mac considered them unreadable. Inserting the same floppies into an external floppy drive on this same machine worked fine. For my testing, getting to the erase dialog was actually a time-saving shortcut, so i kept using the failing internal drive.
After not all that long—maybe another 5 diskette insertion/withdrawal cycles—with my having done nothing other than exercise the drive (the hot 30°C day may have helped. We don’t have whole-house air conditioning), the drive successfully read the 800k floppy. It continued to be unable to read the 400k floppy. Another dozen (give-or-take) disk insertion/removal cycles, and the drive now successfully read the 400k floppy as well.
Note that this was on a floppy drive which had been serviced within the last 17 years. Older drives which have never been serviced in some cases will work just fine, but in other cases may be even more sticky/incorrigible. You may want to keep cycling one or more disks in and out for dozens upon dozens of cycles. If any are especially valuable, it may be wise to use a less-valuable or scrap floppy if you have one. Heat may help, but don’t go crazy: i wouldn’t go farther than putting the drive (or the Mac with covers off) out in the sun with the sun hitting the drive case, for maybe up to half an hour. As good or better: if you have the time and skills, open up and clean and lube the drive. (An article from me on this subject is years or a decade or more overdue. If it ever happens, there’ll be a link here.)
I’ve presented a lot of information already in great detail. Let’s summarize it:
|System 0.7–System 2*
|System 3–System 7.1 Update 3
|Mac OS 7.6–7.6.1
|800k & 1.4MB HFS||Read||No||Yes||Yes||Yes||Yes||Yes|
|OS Erase/(Re)Format||MFS||MFS or HFS||HFS||HFS||HFS||HFS|
This table only covers standard Apple-sanctioned options with stock hardware, for diskettes intended for use on Macintosh computers (not Apple II nor DOS/Windows platforms, nor going cross-platform). It does not cover hardware limitations, such as a Mac Plus which can run up to System 7.5.5, but cannot run a SuperDrive, thus cannot work with 1.4 MB floppies of any format.
Dates are approximate, provided to help people guess what OS might have been used to format/work with floppy disks from which they may wish to gather data. Note that older Macs and Mac OS versions were often used for years and years past the release date shown.
“So wait… what can I do with an external USB floppy drive on a newer (OS X era) Mac?”
A surprising amount!
Please note that my testing has been limited to one sample of one brand/model of drive: VST FDUSB-M, from around the time of the original iMac. Since i have not worked at Apple since the mid 1990s and have not had access to their lab with every Mac since that time, the specific model and OS testing is limited as well (and may or may not be expanded upon in the future). Still, the following data points may prove informative.
I used two test floppies, both 1.4 MB (since we already know that 800k and 400k Mac floppies won’t work). One was formatted Mac OS Standard, a.k.a. HFS. The other was formatted Mac OS Extended, a.k.a. HFS+.
Back in the 1990s during the Vintage Mac (“beige”) era, all 1.4 MB HD Mac floppy disks were HFS format. This was a limitation imposed by the OS, i presume for backwards compatibility and because the main advantage of HFS+ on the original (“vintage”) Mac OS was the change in allocation block size, for more efficient utilization of disk space for high-capacity volumes (hundreds of megabytes into gigabytes). As discussed in napabar’s post on 68kMLA Forums, OS X introduced the ability to format high-density floppies as HFS+. These floppies will work on Vintage Macs, as long as the OS supports HFS+, meaning OS 8.1 or newer.
The first tests involves what happens when these disks are inserted in a floppy drive on a Mac with a version of OS X released since 2005: can they be read? Can they be written to?
The second test: can Disk Utility (re)format the disk? If it can, what are the format options? This is a good indication of overall floppy support for this machine/OS/Disk Utility version combination. It may be important when attempting to download old software off today’s Internet on a modern Mac and “take it back” to a Vintage Mac.Here are the results:
|PowerBook5,6 (PPC)||MacBook1,1 (Intel)||MacBook Air Mid-2010 (Intel)|
|OS 10.4.11 Tiger||OS 10.5.8 Leopard||OS 10.5.8 Leopard||OS 10.6.8 Snow Leopard||OS 10.8.5 Mountain Lion|
|Disk Utility (Re)Format||HFS or HFS+||HFS or HFS+||HFS or HFS+||Will erase (reformat) existing HFS standard floppies as HFS standard, but HFS+ is the only Mac option for floppies with no format or any other format.||FAT and ExFAT (Windows) options only.|
So it looks like if your Vintage Mac is running OS 8.1 or newer, you can use a Mac and OS at least as new as the Mid-2010 Air and the current version of Mountain Lion as of November 2013 and use that new Mac to put software on an existing 1.4 MB HD HFS+ (Mac OS Extended) floppy and take it back to the Vintage Mac. The news is even better if you no longer care about the old Mac(s) and simply want your old Mac data on 1.4 MB HD Mac-formatted (HFS or HFS+) floppies on your much newer Mac: you can just pop those suckahs right into your bought/borrowed/gifted on Freecycle external USB floppy drive and copy that data right on over (and hope that some modern software reads the file format).
If your goal is to transfer Vintage files from the modern Internet or modern archival mass storage back to your Vintage Mac which is running Mac OS 8.0 or earlier, you are going to need to reach back to a Mac which can run OS 10.5 Leopard (Intel or PPC) or earlier so you can create and/or write to HFS (standard, not +) formatted HD floppies. The newest Macs which appear to run (e.g. ship with) OS 10.5 Leopard are the Mid 2009 models. This will take you all the way back to the Mac SE s and Mac II (no suffix)s which had FDHD (1.4 MB high-density-capable) floppy drives, a.k.a. the floppy incarnation of Apple’s SuperDrive. Earlier SE and II models with the 800k drives and all older Macs cannot be assisted by an external USB floppy drive (as noted at the beginning of this article).
I did not do any new (Nov. 2013) testing of this combination. To the best of my knowledge, all external (USB) floppy drives are based around a standard floppy mechanism as used in PC-compatible hardware. I verified in the past that 1.4 MB HD and 720k DS FAT formatted floppies can be read on OS 9 and OS 10.4.11 Tiger on PPC Macs, but i did not perform write testing. During the above testing of the Mac formats, i noticed that all Disk Utility versions i checked had at least the FAT format option available. Newer versions of DU add the ExFAT format. DU for Mountain Lion only formats floppy disks as FAT or ExFAT. To me, this formatting support indicates full read/write support in the OS/Finder, but i did not test it out. In other words, if you have DOS/Win PC 3.5" floppies which you want to use on your modern Mac, seems like you can pop ’em in your attached external floppy drive and go to town.
Vintage Mac users with a Vintage Mac new enough to run whatever version of PC Exchange (or equivalent Apple-bundled software for handling PC-originated media) came with the particular Mac OS in use may have another option to move files from a modern Mac to their Vintage Mac. As recently as the OS 10.8.5 Mountain Lion/MacBook Air Mid-2010 combination, one could attach an external floppy drive and format a 1.4 MB HD or 720k DS (and probably 360k SS but i’ve never tested that) as FAT (listed as MS-DOS in older versions of Disk Utility), load up the files, and via the PC Exchange mechanism have the Vintage Mac read the files. This ought to work for any Vintage Mac for which there was a version of PC Exchange (or equivalent… i think it may have been built into the OS later on). Quick research indicates that a SuperDrive and System 7 are required on the Vintage Mac to use PC Exchange, but i did not research this in depth.
Warning: PC-formatted disks (floppy and otherwise) and other non-Mac-formatted disks don’t understand resource forks. Your Mac-to-Mac files may be damaged in the transition unless they’re compressed, which realistically probably means Stuffit or Zip compression.
“Alright… I’ve got my floppy data on This Old Mac. How do I get it onto my new Mac? They don’t seem to talk to each other!”
You got it! Old Macs have floppy drives, SCSI, and LocalTalk networking. Newer Macs have Optical SuperDrives, FireWire, and Ethernet. What to do?
Trying to span too big an era gap is highly problematic… there really is no way a stock 128k Mac is going to directly talk to a stock G5 desktop or G4 PowerBook/iBook (don’t even think about the MacTels!). Spanning smaller gaps is less problematic, down to the point of being almost easy. Multiple hops may sometimes be unavoidable. The specific solution options depend quite a bit upon the available Macs.
There are likely a few others that can be found by a competent WWW search. These are the ones i know of as i type this. For that matter, this whole section is likely to be less comprehensive than much of what is out there already. I mainly wrote this as a convenient one-stop quick answer spot for the most common scenarios for folks wanting to get stuff off floppies. If you find any pages/sites that are more comprehensive and feel like letting me know, i will certainly consider linking to them. Today, i prefer to type my own thoughts rather than web surf for superior comparables.
Whether this option works at all depends upon exactly what you have and/or can borrow:
I find that these options are usually not available, so i usually move onto, and prefer:
Take advantage of the fact that there exists no Macintosh unable to network. Now, whether it will directly connect to your flavor of network is another question! Even if it does not (or seems like it won’t), this still can be a good way to go.
AppleTalk is my method of choice, especially for Macs of disparate generations. The first 128k Macintosh spoke AppleTalk. The new-in-November 2005 15" PowerBook G4 Dual-Layer with OSeX Tiger 10.4 still speaks AppleTalk. Perfect, right? End of story, right?
First, there is the physical connection layer: Older Macs speak AppleTalk over serial ports. Newer Macs no longer have serial ports, and instead speak AppleTalk over ethernet and AirPort. Older Macs that have ethernet or can be adapted to support ethernet or Wi-Fi are usually quite easy to network to current or at least recent (pre-MacTel definitely works) Macs using ethernet and AppleTalk. The 128k and 512k Macs have to stay with serial port AppleTalk, and if the Mac Plus or newer does not already have an Ethernet adapter, finding one is likely to be difficult.
Second, there is a protocol issue. The original AppleTalk protocol was Apple proprietary, and only works over serial ports. In the mid-1990s, Apple encapsulated AppleTalk datagrams (i may be misusing some of these terms, in their strict sense) inside standard TCP/IP packets, or in English, AppleTalk was now able to operate over TCP/IP networks. This option became available circa Open Transport 1.3, and continued to the end of Mac OS 9. Mac OS X Tiger 10.4 and newer requires AppleTalk to be over TCP/IP, so only Macs that can run OpenTransport 1.3 or later can AppleTalk directly to OS X Macs… if they have the correct hardware for Ethernet (or something else that can handle TCP/IP that the new Mac can also handle).
A low-priority life project of mine is to do further research in this area. Should this ever happen, i plan to eventually update this section with more detailed and carefully verified information. For now, if one straight jump from your very old Mac to your very new Mac is not working, try the Puddle Jumping method of intermediate steps, or some other option.
While not especially elegant, if the older Mac can go online, this may be an easy option.
Any files on floppy disks are by definition small enough to travel well via email. Since email protocols have changed less than those for the WWW, the odds are better getting an old email client working on a very old Mac than getting a modern enough browser going. Authentication may be a problem, since in the old days authentication was not required for sending email, yet in recent years it has become more common, often now mandatory. If you find you cannot send via an old email client, you may need to look into the specifics of how this can be handled via your particular ISP and/or see if there is an alternate email program which supports the authentication your ISP requires. In some cases doing a mail check on a modern computer opens up a window of opportunity for a few short minutes to send from the same IP address without further authentication.
The files should be Stuffed with an appropriate version of Stuffit, or otherwise compressed with a tool which will “fold” the resource fork (where it exists) into the data fork for each file, making a smaller single-fork single file for emailing. Note: there may be issues of lack of compatibility between Stuffit products version 4.5 and earlier and 5.0 and later… intermediate steps may be required. If the floppy material can be Stuffed with a Stuffit product version 5 or newer, that is most likely to work out best. If not, use the newest version which will work on the old Mac/OS. There should be plenty of information on this subject elsewhere, if this brief description is insufficient.
All the old email programs i remember for the Mac Plus and System 7.0 took care of binhexing or otherwise converting the 8 bit file into a bigger 7 bit file for emailing (and any Mac email client on an OS 9 or newer system will have no problem automatically doing the reverse conversion, to the best of my knowledge and experience). You should not have to think about this sort of conversion… i only mention it in case emailing is not working, as an area to investigate. Eudora 1.5.x can be set to handle this, and i vaguely remember its defaults being suitable.
Once the files from the floppy disk(s) are properly pre-processed (compressed with no resource fork on the compressed file) for emailing, just email the file to yourself, either at your own, same email address or another one. There are so many variables in terms of emailing and ISP variations that this page cannot possibly cover them. If email proves too difficult, another method may be a better choice.
If your email is via the WWW rather than a standard email client, most of the issues above apply, yet there may be more or fewer. Again too many variables to discuss. Your best bet for a web browser on the older Mac which will actually work with today’s web mail is iCab. PPC Macs running OS 8.6 or later can and should use iCab 3.0.5 as of this writing (or a newer iCab 3. iCab 4 or later is not an option). Older Macs back to some of those running System 7.0.1• can, with care, run iCab 2.9.9 (available in versions for 680x0 and PPC).
While far from my first choice, if you have/can find FTP space, this can be a good option, as again FTP protocols have not changed over the years anywhere near as much as WWW or even email. No further details here… many Vintage Mac FTP options from which to choose.
Sometimes it is much easier to just use an intermediary system than to try to find a way to get directly from a very old Mac system to a very new one.
What to use here will depend a great deal upon what is readily available. At some future point (if i ever get around to it), either on this page or a separate one, i hope to have an extensive diagram showing what connects to what else successfully. For now, i leave you to your own devices and searches to discover if what you have will interoperate.
If you do not have an intermediary Mac, or perhaps you expect this may come up often in your life and want to have the most flexible Mac for this purpose, there is one series of Vintage Macs which i find to be especially “golden” when it comes to being a file transfer intermediary: the PowerSurge family of PPC desktop Macs. These are the “G2” PCI-based PowerPC Macs, and include:
There are other models of this era which were not strictly part of the PowerSurge family, yet will likely be close enough in abilities to be equivalent in most or all ways. I am thinking specifically of the 7200 and 8200. These were lower-priced transitional models, with many (not all) of the advantages of the PowerSurge models listed above, yet with older, slower processors. This mattered a great deal when these machines were current, for everyday primary computer usage. For occasional light file transfer usage in the present, the older, slower processors are a non-issue. Given the choice and the low/free price of the actual for-sure PowerSurge models listed above, i recommend the latter. If you would like to see the full model enumeration as a bullet point list, for this reason and for another opinion/general edification i recommend Porter Olsen’s digital curation-oriented article Accessing Mac Formatted Floppy Disks without a Kryoflux.
With my 9600/350, i can directly transfer to/from floppy, Zip, USB flash memory, an external FireWire or USB or SCSI drive, CD, DVD, or network in any number of ways to any arbitrarily older or newer (so far as of the date this was originally written) Macintosh. Appropriately configured, the same applies for the other models listed.
I give mine one or more PCI cards for FireWire 400 and USB 1.1, and partition the internal hard drive so there is at least an OS 9.1 startup volume for general use and an OS 7.6.1 startup volume for accessing those old MFS floppies. The floppy drives are clean and ready to go!
For those with limited space and/or who prefer smaller, self-contained systems, the portable Mac equivalent was the PowerBook 3400c. The same considerations which make the PowerSurge desktop models suitable apply as well to the PB 3400c, other than the PowerBook having a PC Card (PCMCIA) slot rather than desktop PCI slots for expansion. There did exist a 3rd. party (VST i think?) Zip drive which could take the place of the floppy drive in the drive bay, though it’s equally good and possibly easier to use an external SCSI Zip drive (far more common)… if you can find the not-so-common DB-25 (Zip drive) to HDI-30 (PowerBook SCSI port) SCSI cable or equivalent adapter.
Please note that the base 180MHz configuration had built-in Ethernet as an option. The 200 and 240 MHz higher-end models had built-in Ethernet as part of their standard configuration. Finding a USB PC Card is likely to not be too terribly difficult. I’m not sure that there ever existed a FireWire PC Card which would work on this model, and if there was one/were any, they were not common when new and would be even more rare now. If FireWire is part of the equation, you’ll do better with a desktop Rosetta Mac.
If Ethernet is not a concern, or you’re willing to add an Ethernet PC Card (and possibly struggle to ensure the OS has compatible drivers and will work with it), two other models become options:
I worked at Apple at the time all 3 of these machines (and the PowerSurge and other same-era desktop machines) were under development/currently being sold. The 2400 models were rare and i have reasons i dislike the PB 1400 models, though honestly my issues with them are germane for primary computer usage in the mid-late 1990s, not occasional mass storage file cross-format transfer in modern times. Any of these three should be good choices, as long as they work and they support the media formats you wish/need to use.
These machines—desktops and portables—have been priced at/near “doorstop”/giveaway value for the last few years… get ahold of one (or more) and hold onto it/them before they all disappear in e-waste!
If you don’t have and can’t get or don’t want access to an actual Vintage Mac, you still have an option, as site correspondent Chris T. reminds me: KryoFlux. KryoFlux is a hardware device which connects a standard (non-Apple) floppy drive to just about any modern Mac or Windows or Linux machine with a USB 2 port. With its supplied software (free for personal use), it reads the actual magnetic flux changes (which is to say: 1s and 0s) right off the floppy disk. The recovered 1s and 0s are stored in an image file which as Chris notes “can then be extracted from these with appropriate software or mounted in software emulators”.Possible advantages of using a KryoFlux setup (my opinion):
This page is not going to further cover the KryoFlux system, as it is a whole different approach and has its own active support community (and because the author of this page doesn’t have one and has never used one). The point of this section is to mention that such a device exists, and may be the best choice for certain people.
If you have further information or specific questions related to floppy drives in Macintosh computers, email me. For more information, there is (was) an excellent website on the history of Apple and the floppy drive.
 Depending upon the exact hardware, this variable speed ability comes from one or both of the drive mechanism circuitry and/or the IWM or SWIM chip (or superseding equivalent) floppy controller on the Mac logic board:
The variable speed of rotation is hard wired into the Apple 3.5 Drive. […]
(Note that the older Macintosh 400K and 800K drives used a timer output from the VIA chip on the motherboard to control the rotation speed, so the speed could be controlled through software. This mechanism was built into the drive for the Apple 3.5.)
See also the Reliability and Simplicity paragraph of this Low-End Mac article.
 See the Sat, 19 Jan 2002 post by iluvmacs on the MacInTouch Mac Plus to iMac page for at least partial corroboration of my suppositions. Especially the part about the 1.6 MB SuperDrive that apparently never happened.
 I tested several 720k DOS (FAT) format floppies on my VST FDUSB-M external USB floppy drive, on both a 9600/350 running OS 9 and a PowerBook G4 15" 1.67 GHz next-to-last model running OS 10.4.11 Tiger: mounted and readable on both systems. I did not test writing to the floppies.
 Systems 0 (or 1) through 4 (or, in my world, 5) were known by the separate, non-matching version numbers of the System and Finder files. What i am calling System 3 is actually System 3.2/Finder 5.3, which i have also seen referred to as System 1.0 (source: d e v e l o p, the disc; issue 2). As Eric Rasmussen points out in his excellent, comprehensive page The develop CD and its spawn, it was not until System 4.2/Finder 6.0 that Apple officially started using single-number system software nomenclature. As a Mac user and member of BMUG at the time, i distinctly remember people still using the split System/Finder reference until System 6 came out. Guess it took some of us awhile to get on board. I very highly recommend Eric’s carefully researched site Apple Macintosh before System 7 for just about any information related to this class of early vintage Macs.
 The statement that the newest Macs able to run OS 10.5.x Leopard appear to be the Mid 2009 models is based upon searching for the newest Macs which originally shipped with some version of that OS. There are usually some “speed bump” newer models which ship with a newer OS X which are still capable of running off older OSes than that with which they shipped. Thus it is likely that certain Mac models newer than Mid 2009 can likely run off Leopard and thus format 1.4 MB HD floppies as HFS standard. I found no easy way to find a list of these models.
The apt term “Rosetta Computers” appears to have been coined by Doug Reside. Cited (with a link to the Reside source) in Porter Olsen’s excellent article Accessing Mac Formatted Floppy Disks without a Kryoflux. Porter’s article approaches many of the same concerns presented right here in my article, from a digital curation perspective.
 For those who were not there, LocalTalk is the proper name for the serial hardware connection between Macs which carries the AppleTalk protocol.
 The common name for the connector is HDI-30. There were positions for 30 pins, but the usual PowerBook-to-device cables only had 29 pins. The special cables meant for connecting a PowerBook (as an ersatz external hard drive) directly to a desktop Mac, ironically with DB-25 connectors on the other end, actually had all 30 pins: the 30th. pin electrically switched the PowerBook into what was then called SCSI Disk Mode and on later/newer Macs lacking SCSI became known as Target Disk Mode. Some 3rd. party adapters have all 30 pins and a switch to select Normal (“I’m attaching an external drive or scanner or whatever other SCSI device to a PowerBook running normally”) or SCSI Disk Mode.
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