Intel MDS Further Information - test-drb@ccmp.vtda.org

1 Nov 2004

Hi Scott
 This is a Series II machine, not a Series I ( no such thing
as a Series I ). The IPC card is the indicator. That was only
used in the Series II's and Series III machines. The Chassis
should also have a non-multibus card called the IOC card that
runs the terminal and the SD controller.
 The IPC card is the main processor card. It is the one that
runs any code that you'd normally run from the disk. Also,
you should note that there is an small interconnect for the
aux bus connector that goes between the two disk controller
cards. This may be bolted to the frame but it need to be there
for the cards to work.
Dwight

...
 From: "Scott Stevens"
&lt;chenmel(a)earthlink.net&gt;

This weekend I had the time to pull open the Intel MDS system I
mentioned last week, and record info and photograph all the Multibus
cards.  I've put the info up on some personal web space.  All are
invited to comment on and advise me on what I've got.

The URL is:  http://sasteven.multics.org/MDS/Intel_MDS_Cards.html

Here's the 'text' of the page, which includes board numbers, etc. (go
to web page for a photo of each board)

----------------
 These boards are out of my MDS system.  It was
targeted as an ICE for
the 8051 microcontroller.  The emulator POD plugs into one of the board
sets below.

This page is organized to document the boards as they are installed in
the Multibus cage from the bottom going up.

---------------------------------

Bottom Board on Rack-

Floppy Disk Interface
Double Density
PWA 123857-002
S/N 023767

This board has a cable plugged into it's top edge connector.

---------------------------------

Next Board Up

Floppy Disk Controller Channel
PWA 10000457-05
(may have copied down one extra 'zero' in above part number)

This board does not have a cable plugged into the 'top' edge connector. 
Edge connector shows 'weathering' from not having connector on it.

---------------------------------

Next Board Up

Trace Board
PWA 162249-001
S/N 13904

J10 and J11 headers which are brought out to the Emulator Pod.

---------------------------------

Next Board Up

Controller Board
PWA 162380-005 Rev M

This board has an 8080A Processor on it.
The Multibus P2 board edge is 'bridged' to Trace Board (above) on a
two-slot interconnect board.
Has header on it brought out to Emulator pod and also power header to
emulator pod.

---------------------------------

 Open Slot, second from top.

---------------------------------

Top Board

I.P.C. board
PWA 123192-003
S/N 084111

This board has an 8085 Processor and array of memory chips.
Also has two 8251 and two 8259 chips.
Board has row of buttons to generate interrupts that faces out to front
of system. 
It appears I have here an 8085 based system.  Is this correct.  It
also appears that there's an 8080 controller as part of the emulation
system.  I'm assuming (?) the system would run with the Emulator
boards (Trace Board and Controller Board) not installed.

Some questions: 

1.  Is the memory array on the top board (board with 8085 processor)
the main system memory.  It looks like four rows of 4116x8, for a
total 64K.

2.  The system has a built in CRT display, and a keyboard input.
Where is the video generated and keyboard I/O circuitry?

Any and all insights into this system are welcomed.  Probably I'll add
in any info I receive into the HTML for the page.

Thanks,
Scott