Rescuing Floppy Disks

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While they were cool-looking, convenient and even somewhat inexpensive after a while, Floppy Disks are out as a medium to store data on home computers. The USB stick, wireless access, the use of the internet, and a whole other range of options have rendered this medium obsolete. That said, a situation now exists where there are millions of these things out in the world, some of them containing rare or unusual pieces of history, and so there's a lot of benefit to getting all that old data off that medium.
This page is meant to be a clearinghouse for various options that a person or group of reasonable technical ability could use to rescue data from floppy disks. If any of these options seem daunting, a number of people have offered to accept floppy disks and pull the data using these tools. 
None of these options should be considered endorsements, and Archive Team does not earn commission from the sale of these items.
=== Some Basic Thoughts on Floppy Disks ===
There are three different main sizes of floppy disks that had the most traction:
* 8" Disks
* 5 1/4" Disks
* 3 1/2" Disks
8" floppies fell out of favor relatively quickly in favor of the 5 1/4" versions. In the late 1980s, 3 1/2" overtook 5 1/4" as the dominant format, but a lot of machines, such as the Commodore 64, Atari 810, IBM PC, Kaypro, Apple II and II, and a range of others all supported the 5 1/4" primarily. 
All floppies work on the same principle: a magnetic disc with a hole in the middle is inside a case, and a disk drive reads the magnetic data off the disc. Some aspects changed - where 8" and 5 1/4" discs had no built-in protection for the magnetic face of the disc except a paper cover, the 3 1/2" versions had a small spring-loaded door that was opened by the disk drive.
Storage could make a huge difference in the lifespan of Floppies, and a pile of disks put inside a box that was stored in a low humidity, non-extreme-temperature environment could last a lot longer than a floppy used constantly that was left on top of a computer monitor for weeks.
We're going to assume you're just trying to take a pile of disks from however far back and transfer the data onto something more recent. In all cases, try and avoid throwing out the original disks after doing transfer, as you might find that the transfer you've done is missing information, or that technology might have shifted in the meantime, allowing better extraction of the data.
=== The Flippy Disk Problem ===
Spend enough time with floppy disk nerds, and eventually you will hear weeping about the "Flippy Disk" situation. We'll use the FC5025 description of the issue here:
Many older computers recorded on only one side of the disk. So, people would fill one side of the disk and then flip it over to store more on the other side. Disks used this way are called "flippy" disks. 5.25" disks have a hole, called the index hole, that lets the drive know if the disk is rotating. (The index hole has other purposes also.) The problem with flippy disks is that when the disk is inserted upside-down, the drive cannot see the index hole. Many drives won't read from the disk unless they can see the index hole. If you have one of these drives, the FC5025 will be able to read from the first side of the disk only. When you flip the disk over to read the other side, the drive will not send any data to the FC5025, and the FC5025 will not be able to read that side. Please note: even the recommended TEAC FD-55GFR drive cannot read both sides of flippy disks. There is no recommended drive for reading flippy disks at this time.
=== The Copy Protection Problem ===
What you're doing, here in the future, is just what the software companies of years past were terrified you would be trying to do: make multiple, potentially unlimited copies of the software on a floppy disk they sold you. To this extent, many companies selling software would enact one of many protection schemes to prevent duplication.
Some would use the documentation or included items in the package and have the software query the user to verify they paid. Some used hardware dongles (although generally this was high-end software, not, say, a game). And yet others implemented copy protection into the disks themselves.
An example of this might be spiral tracking, where a computer would start up off the boot sector of the disk, but then the booted "OS" (really just a control program) would force the drive head to act counter-intuitive to what any regular floppy would be expected to present. For example, a spiral. This meant that a standard disk-copy program would duplicate the drive as if it had regular tracks, but would totally fail on it, and the software was protected. And also un-preserved.
This means that software being run now to duplicate a floppy disk is one good at doing a magnetic copy, since all the other rules are out the window. It means that in cases where a drive shows lots of errors copying a disk, it might not be a bad disk, just the copy protection kicking in decades after it was dreamed up. It's a problem to keep in mind.
=== Methods of Transfer (Hardware) ===
There are currently multiple ways to transfer a lot of floppy disks, some involving original hardware and others involving customized circuits to use modern hardware to pull the data off the disk.
DiscFerret
The DiscFerret is a USB device that reads magnetic flux data from disks at a sample rate of up to 100MHz. It has an interface port that can be connected to most common floppy drives, as well as MFM and RLL hard drives. This allows capture of all data, including copy protection, unusual formats, and mastering data. Though the hardware is quite powerful, the software is under heavy development at this time. A complete floppy format analyzer program is in development. All components of the board (including the hardware, firmware, and software) are under an open source license, with source code and hardware designs available at the DiscFerret Mercurial repositories. There is also a support and development IRC channel, #discferret on Freenode.
At this time the boards are not available for purchase, and the hardware side of the project has been largely discontinued.
SuperCardPro
The SuperCardPro is a USB magnetic flux reading device based around a 160Mhz PIC24HJ256GP210A microcontroller along with 512K of SRAM. As a generic flux reading device, it can handle reading raw flux data (synchronized by index marks) at most common rates. It connects to any mini-shugart (34-pin) interface floppy drive (3.5" or 5.25"), or an 8" drive with the 'wide-shugart' interface, if an appropriate adapter is used. The software allows sector-level copying and decoding of the flux data, as well as raw storage of the flux data.
The SuperCardPro software and firmware is closed source, and old versions of the website, software, documentation and manuals are explicitly excluded from the Internet Archive.
The SuperCardPro hardware is available for purchase (August 2021).
AppleSauce
The AppleSauce FDC is a USB flux reading tool based around a Teensy 3.1 microcontroller development board. The AppleSauce device is used to power and control an original Apple Disk][ 5.25 drive, to image Apple][ diskettes at the flux level.
The AppleSauce hardware, using an original Apple Disk][ 5.25 drive, is capable of reading all quarter tracks up to track 36 or 37 on an Apple][ formatted 5.25" disk in about 3-5 minutes, depending on what tracks are used. With an added (included) index sensor, it is capable of correctly imaging the vast majority of Apple][ software diskettes, whether or not they employ copy protection. It can also do very fast (<1 minute) imaging of unprotected Apple][ diskettes.
The AppleSauce hardware also supports reading from 3.5" Apple][ and Macintosh 800k and 1.44MB 'SuperDrive' external drives, and by using the 1.44MB 'SuperDrive' can also image PC 720K and 1.44MB 3.5" disks.
Copy-protected 3.5" disks for either the Apple][ or Macintosh can be imaged using an (optional) index sensor.
An updated AppleSauce hardware revision for additionally using the 34-pin mini-shugart floppy interface for reading 5.25", 3.5", 8" (with an adapter) drives, as well as any other drives using the same interface, is in development as of August 2021.
The AppleSauce hardware is available for purchase (August 2021).
KryoFlux
 Another choice is a USB device called the KryoFlux connected to a modern floppy drive (3.5" or 5.25"). This hardware solution utilizes a floppy head to read a floppy disk not as a bunch of data but the actual magnetic flux of the disks themselves. What this translates to, in the vast majority of cases, is a disk image that includes any copy protection, unusual write schemes, or trickery. Naturally it captures the full data of the disk as well, and this is likely overkill if you're digitizing a personal set of files, but it's good to know the option is there. Kryoflux boards are for sale at the Kryoflux site. Please note that the Kryoflux software license may cause legal issues if the resulting images are not intended solely for personal use, or the Kryoflux is intended to be used in any commercial or preservation/museum capacity. The personal use license had, in Mar 2012, an anti-compete clause in it, preventing the user from using any competing disk-imaging product or sharing any 'resolved' disk images created with the product, although the license was amended sometime around 2013 to make it somewhat more permissive. The commercial/museum use license for Kryoflux is rumored, as of July 2020, to still have all of these anti-compete clauses and media distribution restrictions in it.
The KryoFlux hardware is available for purchase (August 2021).
CatWeasel
The Individual Computers Catweasel is a PCI card that allows connecting a floppy drive. Just as the DiscFerret and the KryoFlux, it reads disks at the magnetic transition level. It also has SID sockets and Amiga peripheral ports, but the quality and performance of these is disputed and the use is limited.
As of 2012, the CatWeasel MK4plus and other hardware appears to be unavailable for purchase. The official CatWeasel software was last updated in 2009.
FC-5025
A slightly less expensive and more directed version is the FC-5025, from Device Side Data. The FC5025 is a controller board exclusively for use with 5.25" floppy drives. Also consisting of a circuit board with USB and floppy drive connectors, this hardware can read a certain number of disks as well, although there are some disk variations it can't.
ZoomFloppy (C-64 Only)
If you're looking to duplicate just disks for the Commodore 64, the ZoomFloppy from RETRO Innovations will allow you to do so with an original 1541 (and compatibles), 1571 or 1581 disk drive, and plug it via this card into your Windows, Unix, or Mac OSX system. As an extra bonus, it'll allow you to hook up commodore printers to your modern machine, just in case you were looking for that.
There are also the older X1541 series cables but these require a built-in parallel port which most PCs are no longer equipped with.
SIO2PC (Atari Only)
The SIO2PC allows your Atari 800, 130XE, etc to see a PC as another floppy disk drive, making it easy to copy floppies to it, as well as providing a handy way to run your Atari without using a floppy drive. They can be bought various places like AtariMax or you can build your own from the original schematics.
RetroFloppy (Apple Only)
RetroFloppy makes cables allowing an Apple II or III to be hooked up to a modern PC, at which point disks can be copied using the open-source ADTPro software. This method does not support copy-protected disks, however.
FDADAP
The FDADAP is a small adapter by D-bit that allows connecting a 50-pin full sized shugart interface on an 8" floppy drive directly to a standard 34-pin mini-shugart interface floppy port. It takes care of re-mapping the different pinouts of the shugart to the mini-shugart interface, and also has a microcontroller on it to keep track of the current head position. The microcontroller is used to generate the the shugart interface TG43 signal as needed, which is required for writing 8" disks. It also has a convenient 7-segment 2-digit indicator which shows the current track which the drive head is positioned on.
The FDADAP hardware is available for purchase (August 2021).
Disk2FDI
Disk2FDI is a shareware utility written by Vincent Joguin running under DOS to create Formatted Disk Image (FDI) files from actual floppy disks. It reads the following disks to standard sector-dumped disk image files: Amiga (".ADF") Apple disk ][ (".DO") Atari ST (".ST") Commodore 1541 (".D64") PC (".IMG") single-density (".DSK") Please note that to read any of the above disks, except Atari ST and PC disks, you will need 2 floppy disk drives. (The Disk2FDI comes with a modified cable if you order the deluxe version, so it's listed under Hardware.)
GreaseWeazle
The GreaseWeazle is a USB 34-pin mini-shugart floppy interface hardware device series and software developed by Keir Fraser for flux imaging using standard PC-compatible (or other 34-pin mini-shugart compatible) disk drives. The hardware has several active versions:
* The "GreaseWeazle F1" based on the STM32F103 MCU (Cortex M3) "Blue Pill" board, which has very limited (~96k) on-board ram and can only be used in USB streaming capture mode.
* The "GreaseWeazle F4" based on the AT32F403 MCU (Cortex M4) on a more custom board, which has ~128k on-board ram and can also usually only be used in USB streaming capture mode.
* The "GreaseWeazle F7" based on the STM32F730 MCU (Cortex M7) on a more custom board, which has ~256k of ram available and can be used to flux image an entire track at once before sending it to the PC, which is more reliable and less prone to timing dropouts. It can also be used in streaming capture mode, if desired.
Note that other hardware versions are in development as well.
The GreaseWeazle software is open source, UnLicense licensed, and uses features from Keir Frasier's 'disk-utilities' package for decoding flux images, although the 'FluxEngine' software below can also be used with the GreaseWeazle hardware.
The GreaseWeazle hardware is available for purchase (August 2021).
FluxEngine
The FluxEngine is a USB 34-pin mini-shugart floppy interface hardware device and software developed by David Given for flux imaging using standard PC-compatible (or other 34-pin mini-shugart compatible) disk drives.
The FluxEngine hardware is based around the Cypress PSoC5 MCU (Cortex M3), which has ~64k on-board ram and can only be used in USB streaming capture mode.
The FluxEngine software is open source, MIT licensed, and is also compatible with the GreaseWeazle hardware above.
The FluxEngine hardware also supports reading hard-sectored media.
The FluxEngine hardware is available for purchase (August 2021).
Pauline
The Pauline is an FPGA-based, network controlled flux level floppy controller and device emulator developed by Jean-François Del Nero (of HxC Floppy Drive emulator fame). It works with standard mini-shugart compatible drives (3", 3.5", 5.25", 8") as well as Apple II and Macintosh drives. Pauline also has the ability to emulate up to four drives from flux stream based images.
It uses a DE10-Nano FPGA board and runs Linux. All the disk imaging and emulation processes are done internally by the board itself and any device with a web browser can be used to control it. Alternatively, the HxC Floppy Emulator software can also be used to control it. The device also supports some standard network services: ssh, scp, ftp, and Windows SMB share, among others.
Pauline currently supports flux sampling resolutions of 25MHz and 50MHz and is able to stream and store up to 16 channels per signal coming from the floppy drive. The floppy emulation functionality is stream based and can support any disk formats (soft-sectored and hard-sectored disks).
Both the hardware and software is open source, actively developed, and available to everyone.
The Pauline manual can be found here.
Its source code is maintained here.
Firmware updates are available here.
FluxTeen
The FluxTeen is an up-and-coming device not-yet-released USB 34-pin mini-shugart floppy interface hardware device and software developed by PAW for flux imaging using standard PC-compatible (or other 34-pin mini-shugart compatible) disk drives.
It is based on the Teensy 4.1 IMXRT1062 (Cortex M7) with 1MB of ram, and can image a full track at once.
The FluxTeen is designed to image and decode hard-sectored 8" and 5.25" floppy disks. It is currently in the middle stages of hardware and software development although functional.
The "FluxCopy" software package for the "FluxTeen" hardware is currently closed source, and may use custom closed formats for storing the imaged floppy data, but this is subject to change.
The FluxTeen hardware, at this time, exclusively supports reading hard-sectored media.
The FluxTeen hardware/FluxCopy software is still in closed beta testing, and is not yet (August 2021) available for purchase.
DrawBridge
The DrawBridge is an arduino-based USB 34-pin mini-shugart floppy interface hardware device and software developed by Robert Smith, for flux and MFM reading and writing of disks using standard PC-compatible 3.5" disk drives. This software and hardware are particularly focused on interfacing to the WinUAE Amiga emulator.
The hardware, being AVR8 based, is very limited in available RAM and microcontroller speed, meaning it can only work in streaming mode.
The DrawBridge hardware and software are open source under the 'GNU General Public License Version 3'.
The DrawBridge hardware is available but on a waiting list (August 2021), however it is possible for the user to build their own hardware, as it uses all off-the-shelf components and microcontrollers.
=== Methods of Transfer (Software) ===
There are many programs for modern operating systems that can read and write to floppy disks through original hardware.
Raread/Rawrite
Raread and Rawrite are complementary programs that allow the read and write of pre-formatted 3.5 inch floppy disks. These utilities were 
built for DOS systems, with clones written that run on OS/2, NT, and Win32.
For a comprehensive list of floppy disk imaging programs, see this page (FreeDOS).
=== Methods of Transfer (Volunteers) ===
If you're interested in volunteering to transfer disks for people, please put your information here. Note that this same page has been mirrored to here on the Digitize Wiki as well, and people are also actively putting their names in there, so check both places.
* Gene Buckle - geneb@deltasoft.com - I can process Commodore 8 bit media (1541, 1571, 1581). I can also image most 5.25" CP/M formatted disks.
* Ira Goldklang - ira@trs-80.com - Ira's web site describes his offer to convert TRS-80 M1/3/IV diskettes. see this page AND these email instructions. (TRS-80.com)
* Michael Drüing - michael `at` drueing `dot` de (trying to fool spambots here...) - I have a KryoFlux board and can dump and image almost any 3.5 and 5.25 disk at the flux level (except flippy disks). I'm in Germany so if you're in the EU and thinking about getting your disks dumped it might be easier/cheaper/faster to send them within the EU than to send them overseas. I have some possibilities for other media as well (Commodore "flippy" disks might be possible, as well as DDS/DAT or Ecrix tapes, for example)
* Robert Megone - robert@robertmegone.com - Kryoflux user based in the United Kingdom. I can dump 3.5" and 5.25"(with the exception of flippy disks).
=== Methods of Transfer (Service) ===
** RetroFloppy.com - Specialists in data extraction from a broad range of floppy formats and transformation to modern file types.
=== Some Links ===
* General
** A Sad Day for Floppy Disks by Rob O'Hara
* Dumping services
** The C64 Preservation Project's volunteers will dump and return any original disks containing commercial software for the C64.
* FC5025
** Use Guide for the FC5025 Floppy Disk Controller by the Maryland Institute for Technology in the Humanities
** A Review of the FC5025 by Jason Scott
** Rescuing 5.25" Floppy Drives from Oblivion by Spellbound Blog
** Conclusion to CTOS Forensics by Dirk von Suchodoletz of Open Planets Foundation
* ZoomFloppy
** ZoomFloppy Product Page
** ZoomFloppy: First Impressions by Rob O'Hara
* KryoFlux
** The Kryoflux Product Page
** The Software Preservation Society (Makers of Kryoflux)
** The KryoFlux Floppy Controller: A Magnetic Media Miracle
** Archivist's Guide to KryoFlux
* DiscFerret
** The DiscFerret page
** The DiscFerret store (currently closed)
** DiscFerret source code and board designs
** DiscFerret IRC channel (#discferret on Freenode)
Category:Physical media