16 Jul
1998
16 Jul
'98
5:06 a.m.
At 00:05 16-07-98 +0100, ard(a)p850ug1.demon.co.uk (Tony Duell) wrote:
I just might need to trace out the schema. As I've mentioned once before,
and just like you Tony, I have many years of experience in
reverse-engineering circuits, especially vacuum tube equipment, so it's no
big deal sometimes.
The J1 edge connector is the typical gold-plated fingers and seem to be on
0.125" centers while the J3 header is the typical ribbon cable connector
with two parallel rows of 25 0.025" gold pins on 0.1" centers. My guess
also was that J1 is host, J3 is the drive connector.
Could you give an example where we may have seen a QIC36 or QIC02 tape? It
doesn't ring a bell here.
There are actually three boards I need to ID, the third is possibly a tape
controller. Here's the rundown:
#1 A Q-bus dual width board made by DTC. Has a 50-pin header next to a
single ejector handle. All TTL chips, no LSI or CMOS devices. Two 8-section
DIP switches on board. Only markings are a FAB, ASSY, REV and S/N numbers.
The ASSY number is 007-00002.
Could this be a Q-bus SCSI board (I hope, I hope, I hope)? But there's no
I believe it's more likely to be SASI, alas. Now, some SCSI devices
(particularly older ones) will work on a SASI host adapter, so there's
some hope.
The problem is drivers. It's a pretty dumb card - TTL state machines for
the various SASI handshakes. It's certainly not MSCP. But if you feel
like tracing out the schematic and figuring out what addresses do what,
then you probably could write a driver for it. #3 This is what I feel is an Archive tape
controller. It has "ARCHIVE
CORP. Copyright 1983" silk screened onto the component side. No other
numbers on the silk screen, dang it. It is 5.5" x 7.75" with a 50-pin edge
connector (marked "J1") on one 5.5" end and a 50-pin header (marked
"J3")
at the other end. "J2" is a 4-pin recepticle which is the same as the power
connector on a 5.25" floppy or hard drive and is on the edge connector-end
of the board. The EPROM label has 80182-010 on it. Has an 8031
microcontroller chip, an 8155 and an Archive LCC ASIC plus a bunch of TTL
and one small CMOS RAM chip (Mitsubishi M5M2167P-70). Other numbers found
on the board seem to be component part numbers however there is a
hand-written number on the solder side which is 80158-013/A. Could this be
an important identifying number?
My first guess would be an interface between 2 of the following :
SCSI/SASI, QIC02, QIC36. Probably QIC02 -> QIC36, as I _know_ archive
made those (I have the first version - piles of TTL, etc - here). I would
guess J1 is the host connector, J2 is a power connector, wired
conventionally (well, very early Archive drives expected +24V, not +12V)
and J3 is the drive connector.
What pins are used on the 2 50 pin connectors?
-tony
Thanks again,
--Chris
-- --
Christian Fandt, Electronic/Electrical Historian
Jamestown, NY USA
Member of Antique Wireless Association
URL: http://www.ggw.org/freenet/a/awa/