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Floppies are not dead...

24bit

6502
During a correspondence with another member here, Max1zzz pointed me to the fact, that RAW images can be copied to floppy with dd rather simple.

I wrote a first how to here: http://www.emaculation.com/forum/viewtopic.php?f=7&t=8208

On a second thought, I tried the same procedure with a 2DD floppy and yes it can be done and the 2DD volume shows up in FusionPC without issues.

Fusion OS is 7.1 without PC-Exchange installed. Gestalt ID=7, MacIIfx.

YV.jpg


I presume such a dd solution might be really helpful for people with vintage Macs and only a working floppy drive.

As I do not have a old school Mac any more, I would like to ask for confirmation.

Would somebody be so kind to try whether the above does work with a 720k floppy and a e.g. a Mac Plus?

If my memory is correct, I could have 720k floppies HFS formatted with my MacII, but that was ages ago.

(Please bear with me, if this was discussed in the past. OSX 10.5 or lower can of course write HFS floppies from userland.)

 
Would somebody be so kind to try whether the above does work with a 720k floppy and a e.g. a Mac Plus?If my memory is correct, I could have 720k floppies HFS formatted with my MacII, but that was ages ago.
No. (If exchanging data with 800k-drive-Macs were this easy I sort of think it would have been documented by now.)

It may well be "possible" to format a Double-Density floppy to 720k with HFS instead of 800k on a Mac equipped with a "Superdrive"* (I honestly have no idea, it seems like sort of a pointless thing to do), but the IWM controller in the Mac 128k->early Mac SE/original Mac II is incapable of reading a 720k MFM formatted disk. And of course a PC disk controller can't handle the 800k GCR Mac format. This isn't an artificial software limitation, the state machine inside the IWM simply can't do it. (It's hardwired to depend on every 8th bit always being a "1" and throws errors if it doesn't get state transitions at the correct times. An MFM format breaks these rules.)

*Since many (most?) Mac II's were upgraded with Superdrives and SWIM disk controllers your memory may well be correct, although, again, I'm not sure how you'd do it or why. If you're using a DD disk and putting a Mac format on it you probably want to exchange data with Mac Plus-sort of machines which wouldn't be able to read your MFM-format 720k HFS disk.

 
I see. Thanks for reading!

Would have been too easy indeed. :)

Apple File Exchange won't help either I presume, as it was a hardware related issue of the IWM.

All Macs with the SWIM controller should be able to read the 1440k/720k floppies made in 10.8 with dd, right?

I´ll tell my friend rather to do that, than tinkering with BasiliskII build 142 or HFV Explorer on a old notebook.

 
Yes, "dd" is fine for making 1.44MB floppy images to work with SWIM-based Macs. (Lately I've regretted getting rid of my Quadra 650; between the SuperDrive and the Ethernet port data exchange was cake with that box.) I was kickin' that old-school back in 2003-ish. (I was "dd-ing" disks on a Linux box, not OS X, but it's exactly the same thing.)

It might be an interesting experiment to see if a real Mac accepts an HFS filesystem on a 720k floppy. As I said, there's no good reason I can think of to make such a thing on a real Mac but I suppose if you have a pile of 720k disks lying around and want to use them to directly sneakernet files from your emulator setup you could see what happens.

 
Piles of 2DD floppies, he,he. I really had those, like many others here I presume.

I even drilled holes in some to make them HD, it was working mostly.

I sometimes regret giving away our Centris with the 601 upgrade card too.

Maybe my MacII with the Daystar upgrade could have been fixed as well with the help of the very knowledgable members here.

Too late for regretting. :b&w:

 
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