Mystery hardware query

[dempson@actrix.gen.nz (David Empson)]

One of my workmates has been given two mysterious boxes I haven't heard
of before. Does this ring a bell for anyone?

Symbiotic
Mac //c Winchester Adaptor

(And yes, that is how it is written.)

It is a metal box a little larger than a 5.25" floppy drive, with an
internal mains power supply.

It has the following connectors on the back:

5-pin DIN (270 degrees)
DE9 male
IDC-26 male

The name suggests it is some kind of hard drive interface, though I'm
not sure how it is supposed to connect to the computer, and whether it
is an Apple II, Mac or dual purpose product.

One guess is that it is an ST506 interface with a serial connection to
the host computer, but it doesn't have the right connectors - ST506
needs a pair of ribbon cables (one 26-way and one 20-way, if I remember
right). Perhaps it might be SASI? I've never seen one of them.

It appears to have been manufactured in 1984, judging from the serial
number and the date codes on some chips.

It contains two circuit boards:

A permanently mounted board has a 65C02, 2KB static RAM, 12 KB EPROM
(2764 + 2732), 16 MHz crystal.

The second board looks like an Apple II or III slot card, complete with
the standard 50-pin connector and "sloping corner" to allow for the lid.
It says "SYMBIOTIC FAST NOXY CARD" and has another 2 KB RAM, an
unidentified large chip: SCN2651C, and another 16 MHz crystal. It has
two blocks of eight DIP switches on top. The rest of the card is full of
TTL logic but I haven't had a close look for things like PROMs.

The two boards are connected with a 50-way ribbon cable (going to an
Apple II slot connector at one end). The rear panel 26-pin and DIN
connectors go to the FAST NOXY card, and the DIN one appears to go to a
series of LEDs on the card. The DE9 connector goes to the permanently
mounted card with the 65C02.

My workmate is doing some further investigation, including identifing
the chips in more detail and disassembling the ROM. We'll also track
down where the DE9 goes and have a stab at its pinout.

I've taken some photos (using my phone, so not best quality) and can put
them on a temporary web site later if anyone wants to see more detail.

-- 
David Empson
dempson@actrix.gen.nz