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Posted by whiteblossom 14 hours ago

Copy That Floppy – Cambridge guide for preserving data from fragile floppy disks(www.digipres.org)
152 points | 60 comments
samgranieri 2 minutes ago|
Heh. Copy that floppy. I remember being in the computer labs in high school in the mid to late 90s seeing posters saying "Don't copy that floppy" with strong anti-piracy warnings.
AkBKukU 2 hours ago||
I do a lot of floppy imaging and some of my work on it has previously be discussed here[1]. I do not understand where they got the idea of "there are a number of disks that the Greaseweazle struggles to capture, namely the Apple formatted disks. If you have these disks in your collection, you may need to use an Applesauce controller."

The Applesauce is a macOS exclusive tool that has a contingent of dedicated users. While I have not imaged a wide sample set of Apple II and 800k Mac disks specifically, from my current experience the Greaseweazle is plenty capable of reading them. I would speculate the author was trying to use an included diskdef(a flux to binary decoding definition) for an incompatible disk. The Zone Bit Recording[2] Apple drives use is irrelevant when you increase the sample rate of the controller to accomplish the same thing. Similarly C64 disk drives are also ZBR but change the clock rate instead of media speed. So do not think that this means you need multiple drives and controllers when getting into floppy imaging, you can use standard PC drives with a Greaseweazle to read and write Apple II and Mac disks as well as almost anything else.

I have opened an issue on their github page for this site to seek clarification on this.

[1] https://news.ycombinator.com/item?id=39495973 [2] https://en.wikipedia.org/wiki/Zone_bit_recording

cortesoft 57 minutes ago||
A few years back I underwent an effort to image a bunch of old 3.5” floppies I had from when I was a kid. I used KryoFlux, and had a close to 100% success rate (eventually)

Some things I learned:

1. Different drives could read different sectors. I am not exactly sure why, but some disks would show bad sectors when read from one drive, but would have a different set of bad sectors when read from a different one. I had 5-6 different drives I was using (I bought a bunch of used drives, they are pulled from old hardware and resold). I think it likely has something to do with the heads being slightly misaligned or something, so they would struggle with different sectors.

What I would do is scan a disk with one drive, and if I found any bad sectors, I would re-scan with a different drive. I would repeat this process until I had at least one good scan of each sector. I would then pull the missing sectors in one scan from a scan that succeeded on that sector, and would patch together an entire image.

2. I didn’t realize how varied the formats are for disks I had. I remember single vs double sided, but there were quite a few other variations I found in my collection.

3. If you hang out with computer nerds of a certain age, you are going to be surprised by how many of them still have a collection of old floppies that they can’t access anymore. I had so many requests to help archive many different collections!

felooboolooomba 5 hours ago||
As a kid back then, floppies were expensive if you were using your pocket money or hard earned side hustle stash. Floppies were used, abused and reused until that dreadful bad sector. Even after the bad sector if you knew its location. But you knew the floppy time was up.

Kids today will newer know the feeling of unwrapping a fresh package of 10 floppies. The sound, the smell, the texture, the stickers, the formatting, the wast free space, ... as much as retail therapy is a thing, I think that was floppy therapy.

bartread 3 hours ago||
There was a time when, for me at least, the 3.5 inch floppy seemed like the pinnacle of portable storage technology, especially as compared to the cassettes and 5.25 inch floppies I’d been used to.

I made regular use of 3.5 inch disks as portable storage up until, if you can believe it, 2000 when I mostly switched to Zip disks and, occasionally, CDRs. I never found CDRWs that useful.

Writable CD storage was always a bit of a faff to use though, whereas Zip disks behave exactly like floppies, only a lot bigger.

Fast forward to 2002 when I first got home broadband, and it just became easier to simply transfer files directly over the internet rather than toting disks around.

Not long after that cheap USB sticks started to get usefully large but, really, I’ve barely used them in 20-odd years.

It’s funny how, once floppies became too small for most practical uses - even though I’d used them exclusively for 10 years - I didn’t spend much time with anything else before jumping to just relying on the network for file sharing, syncing, and transfers.

Very occasionally I do still use them today: I’ve got an old Korg Trinity synth that uses 3.5 inch floppies for storage, and I’ve got a minty fresh box of them still hanging around in my office. I’ve also got an Amiga 1200 that uses DD as opposed to HD floppies.

actionfromafar 2 hours ago|||
The 1200 is a little weird in that it can also use HD floppies.
bartread 1 hour ago||
Whoa, wait, what? It can? I did not know that. Back in the day I had an A500, and only bought the 1200 decades later. Had no idea it would accept HD floppies. TIL. Thank you!
amiga386 52 minutes ago||
It can't. The GP is mistaken.

The stock A1200 floppy drive cannot read/write HD disks, though you can format most HD disks as DD and physically use them as DD (depending on the brand of floppy disk; back in the late 1990s I used to buy HD floppies because they were the only ones I could easily get, and they were cheaply made and weren't all that reliable on the Amiga, but became more reliable when formatted as HD in an HD floppy drive)

This remains true for the A1200s sold by Escom, which used deliberately downgraded PC HD floppy drives. Still can't read/write HD, and can't easily modify these rare models downgraded drives to support HD.

The easiest and best way to read/write HD floppies is to either buy an external HD floppy drive, available for any Amiga though I believe you'll need Workbench 2.0 or later for it to work, or buy an A4000 or A4000T, the only models of Amiga with a native HD floppy drive.

wolvoleo 20 minutes ago|||
Any HD disk could be formatted as DD anyway. And on an Amiga you had to reformat every disk anyway because they used a different format.
actionfromafar 32 minutes ago|||
Yes I must have mixed it up with A4000, I never had a 1200 so probably just assumed they were similar in that respect too, both being AGA and all.
LargoLasskhyfv 2 hours ago|||
I thought https://en.wikipedia.org/wiki/MiniDisc like that. But, too little too late for too much money.

But conceptually, haptically, optically...phenomenally!

al_borland 56 minutes ago|||
I was a big MiniDisc fan. They were like digital cassette tapes. I could record from the radio, trim out the DJ, re-order the tracks, and give them titles. Looking back, it was all a bit tedious to do on the player/recorder itself, but paired with modern software and a reader for the PC, I'm sure it would be outstanding.
bartread 2 hours ago|||
Yeah, it's funny they never really took off as a data storage format the way zip disks and CDs did.

To me a MiniDisc would have been far better than a Zip disk but I never encountered MiniDisc used in that context. Certainly, whereas all the machines in the computer lab during my masters had Zip drives and floppy drives, making Zip the logical choice for my home PC, I don't ever remember seeing a PC with a built-in MiniDisc drive anywhere at all - not even in computer shops.

Shame really. I'm sure they probably existed but maybe rarely enough that they'd classify as oddware? (HT to LGR for that piece of terminology.)

wing-_-nuts 19 minutes ago|||
>Kids today will newer know the feeling of unwrapping a fresh package of 10 floppies.

Even as an elder millennial most of the floppies I used back then were formatted aol install disks. I don't recall ever buying floppies, but maybe my father did

dghughes 1 hour ago|||
The jump from 1.44MB on a 3.5 floppy to a 650MB CD was astonishing.
artisinal 5 hours ago|||
> the feeling of unwrapping a fresh package of 10 floppies

For us floppies just appeared in the home! I think my dad took them from the office so he could work from home.

mghackerlady 4 hours ago||
Perhaps it's similar to the feeling of unwrapping a pack of CD-Rs
ozymandiax 37 minutes ago||
A practical tip that works miracles on 5.25 diskettes: rub their edges against a table top or whatever, making them sit looser in their sleeves. Does miracles to disks that cause read errors - strange as it sounds.

Also, using an 80 track drive to read a 40 track disk works most of the time. But if you get any read errors, trying with a 40 track drive solves a lot of them!

Lastly, have multiple drives. A read error on one drive might not be a problem on another drive.

I recovered more than a thousand floppies some years ago. And learned that read errors in most cases are not irrecoverable. Try another drive, rub the diskette's edges - the two things that fixed most problems.

Dwedit 5 hours ago||
The rule for preserving floppies is to not use Windows. Windows is known for automatically writing to disks, so you're not preserving the original anymore, you're preserving the changes that Windows made to the disk.
jchw 1 hour ago||
If you're using Kryoflux or a similar controller solution (and they mention several) it should bypass this problem since then the drive doesn't show up as a normal floppy drive at all. So in this case it shouldn't matter.
hypercube33 5 hours ago||
Dont most disks have write protection? Would that not be sufficient?
anjackson 3 hours ago||
Unfortunately, some USB floppy drives ignore the read-write tab. It's not enforced at the hardware level.
tmountain 9 hours ago||
Floppy disks were ubiquitous when I was in college. When I got into Linux, I did an experiment raw writing zeros to floppies with dd to see what percentage of them had I/O errors. I tested with a stack of about 50 of them that were left in our computer lab over the years (different brands). The failure rate was staggering. Something like 30-40% of them had bad sectors. After that, I realized that I could never rely on them as a storage medium for anything important without regular backups.
pdw 8 hours ago||
Floppy reliability dropped of a cliff in the mid-90s. It came to a point where it wasn't unusual to see I/O errors even on completely new floppies.

But with older drives and older media, produced to a higher standard, they were pretty reliable. (After all, IBM invented them to store CPU microcode, they had to be.)

HPsquared 9 hours ago|||
I wonder if anyone made an error correcting driver or file format for unreliable data storage like this. Did anyone ever implement RAId (redundant array of independent diskettes)? Edit: apparently RAR had an option to add internal error correction data to the archive, and you can also use PAR2 files for another layer (I think that's able to reconstruct the archive if one file is totally unreadable)
6LLvveMx2koXfwn 8 hours ago||
. . . simultaneously over-writing the last remaining copy of the original Linux!
SilverBirch 7 hours ago||
Don't copy that floppy! - https://www.youtube.com/watch?v=up863eQKGUI
evandena 2 hours ago|
I love watching old Computer Chronicals episodes and seeing that warning from the Software Publishers Association.
djmips 9 hours ago||
I can't afford an the recommended Applesauce for Apple II disk preservation so I'm hoping that the Adafruit work which added Apple II drive support will work for me.

https://github.com/adafruit/Adafruit_Floppy

Balooga 2 hours ago|
FYI; In South Africa, the 5 1/4 inch is a "floppy". The 3 1/2 inch is a "stiffy". I don't understand why this isn't so everywhere.
mikestew 2 hours ago|
Colloquially it might be correct, but not technically correct. The “floppy” part never referred to the casing, but the media inside.
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