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Mac128
May 3rd, 2009, 10:11 PM
After a long journey, I've finally located the fabled Dr. Dobb's
articles written by John Bass detailing his MacSCSI solution for the
original Macintosh 128K & 512K utilizing the original 64K ROM. I have
published the PDF file at this link (Beware it is a 6MB file):

http://www.mac128.com/MacSCSI.pdf

There is complete software driver documentation and the hardware seems
pretty straight forward. This could well be the start of a means to
equip original 64K ROM Macs with SCSI drives and/or flash drives to
replace the failing HD20 hard drives, something that both the Apple II
community and even the Lisa have enjoyed for several years now.

Hopefully, some of the members of the group with software programming
skills might step up to the challenge of helping to adapt the code to
some contemporary options.

Micom 2000
May 22nd, 2009, 02:22 PM
I have a 512 with a hardware solution of the mid-80s. It's a Dove Macsnap SCSI card and has another Dove memorycard. A 25-pin SCSI socket was mounted over the battery slot. I just checked it out and it has Hi and Lo ROMs and a smaller 128 rom. The memory card has 8 256k chips. There are 2 other vacant banks above the populated one,
the pinholes of which are solder-filled. They must have been meant for additional memory expansion. That's the only thing that makes sense for the unused space and extra circuitry on the card. I'll have to see if I can find any data on expanding the memory.

I have tried several external SCSI HDDs on it, a MI Romac and a GCC Ultradrive 120 and IIRC they seemed to work fine, but never installed any data on them cause I was using them on several later model Macs.


Lawrence

Micom 2000
May 25th, 2009, 08:42 PM
Interesting. A hardware solution to a hardware limitation without any comment.

Reminds me of my Intel Inboard 386 posting which allowed even a common IBM PC to accept VGA and run Windows. Is there some sort of trait of negation which runs thru the psyche of computer collectors which ties them to the drawbacks of older technology and deny that it could be better even within the framework of possibilities of the machine ? Possibly the reason most are into vintage computers ?
A response to the baffling technology of the newest machines. An attempt at empowerment with-in the technology ?

In my case it has until recently been attempting to approach it, since I could never afford the newest whiz-Bang machines. Always on the trailing edge of technology and making the best of it.

Oh well.

Lawrence

Starshadow
June 20th, 2009, 09:16 PM
A friend of mine has a External hard drive that plugs into the floppy port on the back of a 512k or a Plus. He has it paired to a plus but he also has a 512k that I keep telling him it would be the better machine for the strange hd since the Plus has SCSI.

equant
June 21st, 2009, 08:50 AM
After a long journey, I've finally located the fabled Dr. Dobb's
articles written by John Bass detailing his MacSCSI solution for the
original Macintosh 128K & 512K utilizing the original 64K ROM. I have
published the PDF file at this link (Beware it is a 6MB file):

http://www.mac128.com/MacSCSI.pdf

Wow, thanks for scanning and posting that, lots of good info. The SCSI controller chip might be hard to find though.