Would anybody happen to know what the storage size is for a 3½-inch floppy disk? Specifically a "common" floppy disk (like the save icon?)
They seem ubiquitous but I can't seem to get a single answer when it comes to their sizes? Wikipidia mentions 264 KB for HP single sided on this page (https://simple.wikipedia.org/wiki/Floppy_disk) but then also 250 KB with a citation needed on this page (https://en.wikipedia.org/wiki/List_of_floppy_disk_formats)?
Search also gives many different sizes, what gives?
[#]retrocomputing
=> More informations about this toot | More toots from chronocide@mastodon.social
Apologies if I'm showing my age here, but I've never used floppy disks so apologies if this question is missing context!
Every now and again I see people measure things in floppy disks but I have no clue what size that would amount to.
=> More informations about this toot | More toots from chronocide@mastodon.social
@chronocide there isn't one answer to this because it varied depending on whether the disk was double sided and/or high density. So for the IBM PC floppies most people used they were generally either 720kb or 1.44mb, but there were also some other sizes that were possible but rare.
[Edited to remove incorrect info]
=> More informations about this toot | More toots from megmac@treehouse.systems
@megmac @chronocide I don't think 2.88MB disks ever saw the light of day? None of my Windows disks ever had a 2.88 option and I never saw a 2.88 drive. As far as I know it was just a theoretical "someday they might make this" thing but floppies started phasing out in favor of CDs by the time 2.88 might have happened.
I used 1.44MB disks most of of my entire time with floppies with barely a handful of 720s.
Firstly, to be clear, there were three main official floppy disk sizes. 8", 5 1/4", and finally 3.5" in release order. The "save icon" is based on the the 3.5" which had the 720KB and 1.44MB options.
One thing that might skew averages is other hardware sometimes had different formats or similarly sized disks that were actually different in size/shape (see FDS.)
=> More informations about this toot | More toots from nazokiyoubinbou@urusai.social
@nazokiyoubinbou @chronocide you're right Windows didn't come on those. They did use some tricks to use higher than 1.44mb density with existing drives and that was what I was thinking of. But only 1.6mb. https://devblogs.microsoft.com/oldnewthing/20050819-10/?p=34513
=> More informations about this toot | More toots from megmac@treehouse.systems
@nazokiyoubinbou @chronocide that said I definitely feel like I remember 2.88mb drives existing in the wild but, as you say, basically never used.
I think I had a zip drive by then.
=> More informations about this toot | More toots from megmac@treehouse.systems
@megmac @nazokiyoubinbou @chronocide They existed, IBM sold them but you needed the IBM disks to achieve that 2.88MB.
I also remember 1.86MB XDF format that iirc took advantage of a quirk in drives to use extra tracks and variable sector size. I have a copy of PCDOS 7 in that format that I haven't been able to read.
=> More informations about this toot | More toots from rlonstein@mastodon.sdf.org
@megmac @chronocide I never saw that either though?
One thing that some later Windows disks (like 9x era) did do was to compress everything but the system files into a compressed archive (cabinet if I recall -- MS loved their cabinets, still does I think) and decompress that into a small RAMdrive thus allowing them to fit almost two floppies worth of stuff. This was mostly necessary because it had a boatload of different CD-ROM drivers.
Could you be thinking of that? It easily would be 1.6MB or so when decompressed. Maybe even more. Very troublesome if the RAMdrive conflicted with anything (I did have that happen before with something. I forget what.)
=> More informations about this toot | More toots from nazokiyoubinbou@urusai.social
@nazokiyoubinbou @chronocide I mean, I think if anyone would know it would be Raymond Chen ;) they did also use cab files on those disks, but that's a separate thing.
Here's the wiki page on it: https://en.wikipedia.org/wiki/Distribution_Media_Format
And you can see the disk images on the IA: https://archive.org/details/microsoft-windows-95_202404
=> More informations about this toot | More toots from megmac@treehouse.systems
@megmac @chronocide Interesting. I don't think I recall ever seeing DMF disks in those days. I would have been pretty wowwed by the idea. I was always searching for a way to store and move stuff better. (Did a lot with a bunch of different archive formats like LZH and such.)
My guess is they chose to forgo some protections kind of like mode 2 on a CD losing some ECC in favor of more space. If so it may not have been as reliable.
Not really sure. I never saw the DMF disks I guess. But we had Windows 95 on CD with only a bootdisk. (And on that subject I find it really interesting that the first disk in that series is 1.4, not 1.6. I'm guessing it had to use its own software even to read the disks.
=> More informations about this toot | More toots from nazokiyoubinbou@urusai.social
@nazokiyoubinbou @chronocide yeah I think they wanted to make sure that first disk was readable from basically any version of dos anyone might have been using at the time for maximum compatibility, but after that you're in the installer and it can do whatever it wants.
=> More informations about this toot | More toots from megmac@treehouse.systems
@chronocide PCs were normally 1.44MB on them, going upto 2.88MB rarely (some IBM models had the 2.88 drives). Atari ST's and some others had half that at 720KB on 3.5"
=> More informations about this toot | More toots from penguin42@mastodon.org.uk
@chronocide the most common is 1.44MB, that's for a PC formatted disk.
=> More informations about this toot | More toots from Gammitin@mastodon.social
@chronocide Your question was answered several times already, but I gotta say, Wow this makes me feel old. Thanks for that! 😉
=> More informations about this toot | More toots from mike@fosstodon.org
@chronocide the way information was encoded had a big impact on the the amount of data you could put on a 3½" disk. Apple used the GCR encoding which allowed them to store 800 kB where the same physical disk on a DOS machine which used the MFM encoding would contain 720 kB, the Amiga also used GCR and managed to squeeze 880 kB in the same disk.
=> More informations about this toot | More toots from thias@mastodon.social
@chronocide
the original Mac launched in 1984 with a 400kB single-sided 3.5” floppy drive as its only storage medium.
That doubled pretty quickly to 800kB double-sided by 1986 and then High Density drives arrived in 1989, bringing the common 1.4MB size with them.
PCs used the same drive mechanisms but a slightly different recording method (CAV vs CLV) and so stored slightly less per disk.
=> More informations about this toot | More toots from shyra@bitbang.social
@shyra @chronocide Seconded. By the 90s when I was using them, the 1.4MB number was ubiquitous.
=> More informations about this toot | More toots from kwf@social.afront.org
@chronocide@mastodon.social mine are 100kb
=> More informations about this toot | More toots from Stellar@mk.absturztau.be This content has been proxied by September (3851b).Proxy Information
text/gemini