Need A MacBottom Serial Driver for 128K/512K

[Mac128]

So I just picked up this MacBottom serial hard drive for the 128K/512K. It's a pretty cool thing, but nearly useless without a driver. Anybody got any idea where I might find one? Otherwise, could I use some other generic drive formatting software from the era that looks for drives on the serial port, where Apple told developers to implement hard drive interfaces?

This MacBottom oddly has a MiniScribe drive (model 8425) from 1987 in it. Not sure if it is a replacement or MacBottom was still making serial drives for the 512K as prices made them more affordable. Either way it's a loud mother! I have no idea the capacity, but it's a half-height, 3.5". It appears to have a 54-pin connector on it, but assuming there's any data on it still (probably the blessed driver I need!), I'm not gonna be able to read it even if it's SCSI compatible anyway.

Interestingly it has a gold-plated 68008 processor onboard. It also uses the exact same square-shaped & coloured connector as the original Mac mouse and appears to have a serial pass-through port, along with a couple of internal dip-switches. The most amazing thing is it has NO power switch. It is designed to come on automatically when the Mac turns on. And it does all of this perfectly well. However, a standard boot disk will not mount it via normal startup (which is to be expected). Unlike the HD-2o it's only about 2-inches tall and only has vents on the bottom and top. I really should post some pictures when I have a chance to take a few.

So, anybody got any ideas how I can access this ancient beast?

UPDATE: Found this: http://www.redhill.net.au/d/d-a.html indicating a 20MB MFM drive and the specs: http://www.alyon.org/InfosTechniques/informatique/drives/miniscribe/mfm/8425.txt

 

[Charlieman]

Sorry, Mac128, but the only way that it will work is with the original installation disk. The original Mac OS did not realistically support "external drivers". The INIT interface existed but was poorly documented, so manufacturers of serial hard disks inserted the driver code straight into the System file. Depending on the manufacturer, you received a new boot floppy or a disk that would patch an existing boot disk. Apple were continually making major changes to the Finder and System at this time, so version compatibility is a further problem.

As you've discovered, prior to SCSI, most third party disk manufacturers used generic MFM drives. Plus a serial or floppy port interface to connect to the Mac. I think that we must assume that all OEM interface boards are different and require individual drivers. But it is always possible that the design was shared by other manufacturers.

Mac128: Mail me privately for a copy of my notes about HD20 alternatives.

 

[JDW]

What's the 68000 doing on an external hard drive? I'd like to know its specific function.

Charlieman, are these notes you mention too private to make public? Could you put them on the web in Google Docs format for us?

 

[Charlieman]

Charlieman, are these notes you mention too private to make public? Could you put them on the web in Google Docs format for us?

I'm reluctant to share work in progress of this kind because it may contain factual errors or may be open to misinterpretation. There is enough inaccurate information on the internet already, but when I'm confident about stuff, I share it more widely. See http://www.vintagemacworld.com/.

Using Google Docs to share information? Sounds like a good way for collaborative working, but I need to take a better look.

 

[Charlieman]

Interestingly it has a gold-plated 68008 processor onboard. It also uses the exact same square-shaped & coloured connector as the original Mac mouse and appears to have a serial pass-through port, along with a couple of internal dip-switches. The most amazing thing is it has NO power switch. It is designed to come on automatically when the Mac turns on. And it does all of this perfectly well.

A serial pass-through port was common on serial port drives. Typical buyers were already using the two ports on the Mac for an ImageWriter and for a modem, so the pass-through port was a big selling point. Some drives also functioned as print spoolers for an ImageWriter.

The drive powers up by detecting the +5V line. Thus the drive will not work with a Plus onwards unless you provide an alternative +5V source.

See:

http://docs.info.apple.com/article.html?artnum=3202&coll=ap

The 68008 is unsurprising and would have been used as a general purpose controller. It appeared on a few third party NuBus serial boards.