Originally Web posted Tuesday, 13 May 2008.
Content last modified Monday, 30 December 2013 .
External links last verified Thursday, 28 November 2013.

Working with Macintosh Floppy Disks in the New Millennium

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.


Floppy Can’t Be Read

“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:

400k and/or 800k Floppies with an External USB Floppy Drive

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![1]

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 causes 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[2]. 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[3]. 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.

400k Floppies and Mac OS 8.0 or Later

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.

“Huh? Whut?”

MFS — Macintosh File System

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[4], 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.)

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!

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.

Any Floppy Format: 1.4 MB HD, 800k DS, 400k SS: Some Work, Some Don’t

Defective Floppy
  • Try inserting it again… and again… and again…. If you get it to mount, copy the data right away!
  • Most of the usual repair utilities that can repair hard drives can also fix floppy disks. Try what you have. I start with the latest version of Apple Disk First Aid my Mac will run (8.6.1 for Power PC Macs, 8.2 for 32-bit 680x0 Macs, 7.2.4 for 24-bit Macs), then move to AlSoft DiskWarrior 2.1.1 (end of the 2 series). I’ve not been desperate enough to go beyond these for the very few floppies unable to be fixed by these two programs.
  • There used to exist some old custom floppy fixing programs. I never used these much, and don’t know if they can do anything that DFA and DW cannot.
Floppy Drive Alignment
Drive alignment varied quite a bit. It is very possible that the drive that originally wrote the disk, the drive you are now using to read the disk, or both, are/were misaligned. Try another drive for reading. Also, the insert again again again trick can sometimes help here, as well.

The Rest of the External USB Floppy Story

“So wait… what can I do with an external USB floppy drive on a newer (OS X era) Mac?”

A surprising amount!

Mac-Formatted HD 1.4 MB Floppy Disks in a USB External Drive with modern Macs

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 no longer have access to their lab with every Mac for the last 7 or so years, 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+. One of these two formats will normally be found on all 1.4 MB HD Mac floppy disks from the Vintage Mac (“beige”) era.

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 is also known as the 15" PowerBook G4 1.67 GHz January 2005 a.k.a. 15" PowerBook G4 Aluminum 1.67 GHz low-res. and/or single-layer (optical) SuperDrive a.k.a. the very next-to-last ever 15" PPC PowerBook.
MacBook1,1 is also known as the very first model white MacBook.
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
HFS Read Yes Yes Yes Yes Yes
Write Yes Yes Yes No No
HFS+ Read Yes Yes Yes Yes Yes
Write Yes Yes Yes Yes Yes
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 (no, the Air isn’t getting 10.9 Mavericks just yet) 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 7.6.1 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. The newest Macs which appear to run (e.g. ship with) OS 10.5 Leopard are the Mid 2009 models[5]. 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).

PC Formatted (FAT etc.) Floppy Disks in a USB External Drive with modern Macs

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.


Getting Data from Old Mac to New Mac

“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.

Some Options

  1. Sneakernet: Common Mass Storage Device (floppy, CD, Zip, Hard Drive, Flash Drive,…)
  2. Networking
    • Local Network
    • Internet
  3. Puddle Jumping (intermediate smaller steps)

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.

1. Sneakernet

Whether this option works at all depends upon exactly what you have and/or can borrow:

External (USB is all i’ve ever seen) Floppy Drive
The natural response would be to get a floppy drive for the new Mac (bought or borrowed), and just stick in the floppy. As discussed in the section above, this is an excellent way to go for 1.4 MB HD floppies (details in that section), yet is not likely to work for older 400k SS and 800k DS Mac floppies, for reasons discussed further above. (Ironically it probably will work for 360K SS and 720K DS floppies from other platforms.)
SCSI CD-R or CD-RW Drive
This will jack right in (maybe with adapters) to any Mac from the Plus through the PB G3s and somewhere in the early Blue & White G3 desktops (though there are better options for anything that new). Add an appropriate Toast (not sure there was one for the Plus), write that CD, drop that CD in the new Mac, and get happy. Note that older versions of Toast, which may be required for the earliest Macs, will only support the oldest 1x/2x SCSI drives. This may not be the best way to go for 68000 Macs.
Zip Drive
You may hate it, and most folks don’t recommend it for long-term storage, yet this format may bail out your butt! Attach that SCSI Zip drive to the same machines just listed (again, this gets silly once one gets to the Power PC Macs… there are easier options), copy to a Zip disk. Take that Zip disk and drop it in a USB Zip drive attached to the modern Mac. Hey, lookie there… there are your fossilized files!
Macs with Add-Ons
Your older Mac, especially PCI Power Macs, may have add-ons like an ATA hard drive bus, USB, or FireWire. If any of these are available, it is very likely that an appropriate device can be attached, loaded with data from floppy (or wherever) on the old Mac, and then disconnected, moved, and reconnected to the new Mac to complete the transfer. Beware of missing drivers or incorrect driver versions blocking progress!

I find that these options are usually not available, so i usually move onto, and prefer:

2. Networking

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

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?

Wrong.

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).

I am slowly doing further research in this area, and 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.

Internet

While not especially elegant, if the older Mac can go online, this may be an easy option.

Email

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. 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.

Web Mail

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).

FTP

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.

3. Puddle Jumping

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, 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:

Why are these so special?

There are other models of this era which may or may not strictly be part of the PowerSurge family, yet may be close enough in abilities to be equivalent in most or all ways. I am thinking specifically of the 7200 and 8200, models with which i have not had enough experience to precisely recall their suitability. Given the choice and the low/free price of the actual for-sure PowerSurge models listed above, i recommend the latter.

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!

These machines have been priced at/near “doorstop”/giveaway value for the last couple of years… get ahold of one (or more) and hold onto it/them before they all disappear in e-waste!


KryoFlux: A Whole Different Approach (Mac OS X/Windows/Linux)

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): Possible disadvantages 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.


[1] 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.)

--
David Empson
dempson@actrix.gen.nz

See also the Reliability and Simplicity paragraph of this Low-End Mac article.

[2] 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.

[3] 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.

[4] 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[smile]. 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.

[5] 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.

[6] For those who were not there, LocalTalk is the proper name for the serial hardware connection between Macs which carries the AppleTalk protocol.


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