13 Sep
2009
13 Sep
'09
10:15 a.m.
Hi Richard,
Looks like you got a nice computer from that auction. There are a few
different possible configurations when it comes to floppy disk drives.
I probably will be telling you things you already know, since you used
these systems in the past. Strictly speaking, if you have a 225, that
implies an 8085-based cpu board with 64k bytes of RAM on that board. It
also implies that the boot drive is the internal drive being controlled
by the IOC (Input/output controller) back panel board. That board has
imbedded on it a single-density controller. To use that configuration
there would be a 50-pin wide ribbon cable from the IOC to the Shugart
SA801 drive. In this standard configuration the internal drive is
single-density single-sided.
There was an option Intel sold that upgraded the internal 801 drive to
work in a double-density mode. That included a two-board multibus set
that could control up to four drives. Normally that two-board set
controlled up to two external two-drive packages. So up to four
double-density single-sided drives total. They also sold a special
cable that allowed that internal two-board-set to control the one
internal drive. That cable went from the interface board of the
two-board set to two connectors. One connector is the 50-pin edge to
the 801 drive directly. The other connector is a 37-pin D-type
connector that attaches to the back panel of the MDS and is for
controlling a two-drive external box. There are other permutations, but
that is the most common way to get the internal drive to be double-density.
It sounds, from your e-mail, that you may have that optional
configuration. So I have a question. What is set up in your system to
control the internal drive? The difference is whether it is
single-density or double-density.
I'm going to cc this to the classic computer list as it may be
interesting to some others there.
I should be able to help you with software, but whether you need
single-density or double-density is significant.
Dave
Richard Main said the following on 9/13/2009 11:59 AM:
Dave,
I was an engineer for Ford Aerospace in 1976 and I got my department to buy
an Intel Series II MDS-225 with an MDS-DDS and UPP-101. I used it to
develop code for Intel SBC-80/20 boards we used in some satellite downlink
equipment. I got pretty good with ASM-80/85 and even microFORTH. I bought
serial #6 from FORTH, Inc.
Last week one came up on eBay and I was the high bidder at $235.50 (item
200377495743). When it arrived, I opened the covers and found a few cables
unplugged on the I/O board and a switch in the wrong position. Fixing that,
the unit signed on with the monitor. Seems to be completely functional. It
is equipped with one built in SA801 DD disk drive, a two board disk
controller, and a three board plus pod ICE-86A.
I contacted you because I have zero software. At a minimum, I need the
ISIS-II OS. Be nice to get the ASM-80/85, ICE-86, and UPP software. A copy
of microFORTH for the MDS would be especially cool.
Best regards,
Richard
-----Original Message-----
From: Dave Mabry [mailto:dmabry at mich.com]
Sent: Sunday, September 13, 2009 4:51 AM
To: mainpatents at gmail.com
Subject: Re: Intellec MDS questions
Hello Richard,
I have most of what was ever available for the Intel MDS computers.
What is it that you would like?
Tell me a little about your MDS please. I'm always interested in those
beasts.
Thanks,
Dave
Richard Main said the following on 9/10/2009 2:23 PM:
Dave,
Do you have any Intel ISIS-II OS diskettes available? I have a Series II
MDS-225.
Richard Brewster Main, Esq.
Patent Attorney
9832 Lois Stiltner Ct.
Elk Grove, CA 95624
mainpatents at gmail.com
http://mainpatents.com/
cell: 650-575-4624
FAX: 650-641-3126
home: 916-494-2571