Mac OS 9 Lives

Classic Mac OS Hardware => Storage => Topic started by: giovariot on March 27, 2020, 06:35:59 PM

Title: PowerBook G3 PDQ 400/800k support
Post by: giovariot on March 27, 2020, 06:35:59 PM
I recently bought a 661-2048 floppy drive for my PDQ G3 PowerBook.

I read everywhere on the internet that the PDQ floppy was the last SuperDrive one in a laptop, so I was very surprised to discover that my unit (marked 821-4156-A) doesn't read DS 800k floppies, not even through DiskCopy.

I noticed there are 2 different versions of the floppy drive for PDQ G3: 821-4156-A and 825-4267-A. I own the first, are they just two revisions of the same thing or is the 4267 the SuperDrive while the 4156 is a normal one?

Thanks in advance, I couldn't find this info anywhere.
Title: Re: PowerBook G3 PDQ 400/800k support
Post by: FBz on March 27, 2020, 07:00:28 PM
May be of no help, but Adam Rosen (RIP) on a webpage about his Wallstreet laptop covers this a bit in the comments section: http://vintagemacmuseum.com/vintage-mac-museum-workhorse-wallstreet/

(Adam states on that page that he shuffles bothersome 800k & 400k discs over to a Mac Plus.)

(http://macos9lives.com/smforum/index.php?action=dlattach;topic=5402.0;attach=7335;image)

Anybody else, comments / insights?
Title: Re: PowerBook G3 PDQ 400/800k support
Post by: giovariot on March 28, 2020, 02:00:06 AM
Wouldn’t it be supposed to at least show me 800k format options in the “unsupported disk format” dialog? It only shows me 1.44 hfs/hfs+/prodos.
Title: Re: PowerBook G3 PDQ 400/800k support
Post by: GaryN on March 28, 2020, 03:20:03 PM
Wow. Curiosity (and excess virus time) got me and I found that:
The "last" Powerbook that officially came with a Superdrive was NOT your PDQ, but rather the Wallstreet  just before. That there is info on the internet that says it was the PDQ might mean some PDQs got one or simply that most people can't tell the difference between a PDQ and a Wallstreet.

Yup…that sucks for you. The problem with Superdrives is that they require a special drive controller and variable-speed motor to squeeze that extra few Kb of data onto the disk. That means of course, that even if you were to find one from a Wallstreet, there's no guarantee it will work in your PDQ because the drive controller might NOT reside in the drive itself. I do NOT, repeat DO NOT know that for certain so you may have to continue your search for info but don't be surprised if it's true.
Title: Re: PowerBook G3 PDQ 400/800k support
Post by: giovariot on March 31, 2020, 01:48:16 PM
Wow. Curiosity (and excess virus time) got me and I found that:
The "last" Powerbook that officially came with a Superdrive was NOT your PDQ, but rather the Wallstreet  just before. That there is info on the internet that says it was the PDQ might mean some PDQs got one or simply that most people can't tell the difference between a PDQ and a Wallstreet.

Where did you find this info?

Quote
Yup…that sucks for you. The problem with Superdrives is that they require a special drive controller and variable-speed motor to squeeze that extra few Kb of data onto the disk. That means of course, that even if you were to find one from a Wallstreet, there's no guarantee it will work in your PDQ because the drive controller might NOT reside in the drive itself. I do NOT, repeat DO NOT know that for certain so you may have to continue your search for info but don't be surprised if it's true.

Yes, I know, GCR is a proper (but smart) mess. Do you know if there's any way to get to know *if* the drive has an internal controller? Does anyone know of a service manual for those 661-2048 floppy drives?

Thanks in advance.
Title: Re: PowerBook G3 PDQ 400/800k support
Post by: Philgood on April 04, 2020, 02:42:40 AM
I would ask Bruce from http://recapamac.com.au
He's a chap from Australia. Very nice person. Worth a try.
Title: Re: PowerBook G3 PDQ 400/800k support
Post by: IIO on April 04, 2020, 06:17:17 AM
more modern drives usually dont read 800k disks.

if you want read in data from atari or dos systems your best bet is to have a machine froj these das which also supprts 1.44 disks and copy your data to there. on the atari side 1.44 mb support started with the STE.
Title: Re: PowerBook G3 PDQ 400/800k support
Post by: giovariot on April 07, 2020, 06:38:19 PM
So...

PowerBook G3 PDQ, like Wallstreet, can and will read 800/400k DD GCR disks, I can confirm it in a definitive way (checked 3 times that my logic/cpu board are PDQ).

Also as stated here:
May be of no help, but Adam Rosen (RIP) on a webpage about his Wallstreet laptop covers this a bit in the comments section: http://vintagemacmuseum.com/vintage-mac-museum-workhorse-wallstreet/

(Adam states on that page that he shuffles bothersome 800k & 400k discs over to a Mac Plus.)

(http://macos9lives.com/smforum/index.php?action=dlattach;topic=5402.0;attach=7335;image)

821-4156-A and 825-4267-A are probably two revisions of the same thing. This 4156 contains a Mitsubishi MF355H-497MAC, which is actually a SuperDrive.

Why wasn't mine reading DD disks? What was the culprit? It was the tiny switch to detect HD floppies: the pin that switched drive mode wasn't there anymore.

So... After a bit of welding I present you the working solution: short to read DD floppies, open to read HD ones.
Title: Re: PowerBook G3 PDQ 400/800k
Post by: FBz on April 07, 2020, 07:42:08 PM
Congratulations Giovariot!

I apologize for my doubting of your SuperDrive’s capabilities
and commend you on your dogged perseverance.
Here’s to your success! Well done indeed.
Title: Re: PowerBook G3 PDQ 400/800k support
Post by: giovariot on April 08, 2020, 11:09:35 AM
Thanks a lot! But I'll pass my huge thank you to DiskDup that's allowing me to save all that data off hundreds of floppies :D

And a bad mark to Apple for not allowing MFS read support on Mac OS 9 :D