A Bit Of A Rarity

[fri0701]

Unless there's something unique about the geometry of Mac prototype Twiggy drives, which I suspect is unlikely (but have no idea either way), backup via BLU is likely to work for a disk in fair condition.

From a 2013 thread about one of the other two Twiggy Macs:

The Lisa 1's file format is completely different than that of the early Twiggy Macintosh's file format. This is why we needed to use the "BLU" (Basic Lisa Utility) in order to archive and subsequently duplicate these 2 Macintosh Twiggy disks. The "BLU" (Basic Lisa Utility) has several functions - one of which is to copy any data on a disk (bit-for-bit) that is introduced.

@OldMacGuy - Sounds like a good first step will be to find someone (ideally) local with a Lisa 1, who should be able to read and back up your disk over a serial connection to a modern computer. I'd recommend pursuing a backup now before continuing to test your drive with that disk, so you don't lose any data or corrupt the disk during your testing!

As for the drive itself, there's been some good discussion about Twiggy servicing over at LisaList2 lately. Perhaps you'll find that useful at a starting point:

https://lisalist2.com/index.php/topic,80.0.html

If the controller board on the drive is identical to the one used in a Lisa, I wonder if the whole drive could be hooked up to a Lisa 1 and "exercised" by BLU, which would give you an indication as to whether or not it's working properly. Obviously, you'd have to make *absolutely* sure everything was identical before attempting this...

 

[olePigeon]

I'm still convinced the first step should be contacting Marc, who might be able to get him in touch with a real Apple Engineer who worked on the project.

 

[snuci]

If anyone wants to lend a hand with backing up the FileWare floppy and/or troubleshooting the Twiggy drive, I would be eternally grateful. I know this is a special Mac, one of only 3 of its kind known to exist. I’d love to get it working again.

@OldMacGuy I recently restored my Lisa 1 with dual Twiggy drives just this past weekend.  You can see a quick demonstration and hear the variable speed Fileware diskettes in it below.

Stepleton helped me out with my Lisa and would be a great help but if you need someone a little closer, I am in Canada at least.  I'd be happy to back up the Fileware diskette in BLU.  I could also take a look at the drive, if you wish and try it on a Lisa, if it's compatible.  I would suspect it is but I'd have to take a closer look at the top/bottom boards.  

I don't know how to add a YouTube link without it embedding the video here so here is my quick video. 

 

[stepleton]

If the controller board on the drive is identical to the one used in a Lisa, I wonder if the whole drive could be hooked up to a Lisa 1 and "exercised" by BLU, which would give you an indication as to whether or not it's working properly. Obviously, you'd have to make *absolutely* sure everything was identical before attempting this...

Mac Twiggy drives have a different connector altogether---20 pins as opposed to 26 or so. It's possible you could work up an adaptor, but I wouldn't volunteer to do it for you :lisa: .

Another possibility would be to swap the digital board (lower board) on the drive for a digital board from a Lisa Twiggy drive, then stick the resulting Frankenstein into the Lisa. Here too I would explore other options first.

There is a Twiggy expert in the UK who would be thrilled I think for the chance to learn about the Mac drive specifically. He's been studying Twiggy drives for a long time and is probably a good person to know in your quest to put the drive in working order (assuming it is not in working order already). I'll point him at this thread.

 

[Triptech]

The Mac Twiggy has a custom built digital board made purely for the Mac, the Analog is the same in the Twiggy. You need to contact James MacPhail of Sigma Seven , Maker of the X/Profile and the BLU Software as he helped to restore the other two Twiggy Macs and backup the software. As each one had different versions of ROMs He is the only person who has the expert knowledge to help you with this Twiggy Mac.

 

[OldMacGuy]

@OldMacGuy  I would recommend getting in touch with CuriousMarc:

https://www.curiousmarc.com/

I bet he would absolutely be interested in getting that machine going.  He's local here to the Bay Area in California, but has friends in high places at the Computer History Museum and actual Apple engineers who worked on the original Macintosh team.

Thanks again, olePigeon. I just emailed Marc.

 

[OldMacGuy]

The Mac Twiggy has a custom built digital board made purely for the Mac, the Analog is the same in the Twiggy. You need to contact James MacPhail of Sigma Seven , Maker of the X/Profile and the BLU Software as he helped to restore the other two Twiggy Macs and backup the software. As each one had different versions of ROMs He is the only person who has the expert knowledge to help you with this Twiggy Mac.

Thanks, Triptech. I just emailed James.

 

[OldMacGuy]

Mac Twiggy drives have a different connector altogether---20 pins as opposed to 26 or so. It's possible you could work up an adaptor, but I wouldn't volunteer to do it for you :lisa: .

Another possibility would be to swap the digital board (lower board) on the drive for a digital board from a Lisa Twiggy drive, then stick the resulting Frankenstein into the Lisa. Here too I would explore other options first.

There is a Twiggy expert in the UK who would be thrilled I think for the chance to learn about the Mac drive specifically. He's been studying Twiggy drives for a long time and is probably a good person to know in your quest to put the drive in working order (assuming it is not in working order already). I'll point him at this thread.

Indeed, the Twiggy drive in the Mac has a 20-pin connector.

 

[tattar8]

As someone mentioned, the ROM really needs to be preserved from this thing.  Do you know how to dump it?

Have ROMs from either of the other two Twiggy Macs been dumped?

 

[OldMacGuy]

As someone mentioned, the ROM really needs to be preserved from this thing.  Do you know how to dump it?

Have ROMs from either of the other two Twiggy Macs been dumped?

The ROMs of the other 2 were dumped. I just emailed the person who dumped them: James Macphail of Sigma Seven Systems in Vancouver BC. Hopefully I’ll hear from him soon.

 

[tattar8]

Good luck!

Any idea if those ROMs are on the Web somewhere?

 

[Torbar]

Awesome find!  Glad it made its way to a collector rather than a landfill.

The book "Revolution In The Valley" is all about the making of the original Macintosh, written by much of the team,  most of which has been posted to folklore.org,  so here's a relevent story about them switching from the Twiggy to the Sony drives

https://www.folklore.org/StoryView.py?project=Macintosh&story=Hide_Under_This_Desk.txt

Whole site and book is worth checking out

 

[OldMacGuy]

Awesome find!  Glad it made its way to a collector rather than a landfill.

The book "Revolution In The Valley" is all about the making of the original Macintosh, written by much of the team,  most of which has been posted to folklore.org,  so here's a relevent story about them switching from the Twiggy to the Sony drives

https://www.folklore.org/StoryView.py?project=Macintosh&story=Hide_Under_This_Desk.txt

Whole site and book is worth checking out

awesome site. I’ve read every page on folklore.org. Great stories about the gestation and birth of a world-changing product. History told by those who made it.

 

[tattar8]

The ROMs of the other 2 were dumped. I just emailed the person who dumped them: James Macphail of Sigma Seven Systems in Vancouver BC. Hopefully I’ll hear from him soon.

It looks like the ROMs out there are different from yours -- they have the normal blinking ? in a disk, not the symbol in one of your photos.

 

[slomacuser]

I can upload them to garden, they are ver 4.4 and 4.3 ...

 

[slomacuser]

I made a chart back in 2016

 

[tattar8]

I can upload them to garden, they are ver 4.4 and 4.3 ...

Thanks, that would be great!  Although the icon in your graphic seems to be yet another version than the one in OP’s photo.

 

[slomacuser]

They are up on garden, my graphics are from version 4.3 the 4.3T ROM is from 07/04/83, ROM 4.4T version looks very similar to standard Macintosh 128k ROM.
Except it has a different floppy disk driver.

 

[OldMacGuy]

They are up on garden, my graphics are from version 4.3 the 4.3T ROM is from 07/04/83, ROM 4.4T version looks very similar to standard Macintosh 128k ROM.
Except it has a different floppy disk driver.

If/When I get the ROM dumped, I will make them freely available to the community. Per DogCow’s research, the 2.45 ROM is from mid-March - mid-April 1983.

 

[stepleton]

If/When I get the ROM dumped, I will make them freely available to the community. Per DogCow’s research, the 2.45 ROM is from mid-March - mid-April 1983.

Thanks for doing this. I can't really understate how much I've gained from all of the materials the community has shared on outlets like Bitsavers, Macintosh Garden, the Internet Archive, and so on. I always try to pay it forward with stuff from my own collection.