Message: 2
Date: Fri, 14 Feb 2014 09:03:34 -0800
From: Christian Kennedy<chris at mainecoon.com>
To: "General Discussion: On-Topic Posts Only"<cctech at classiccmp.org>
Subject: Re: DG Nova 1210
Message-ID:<F2CB477E-C307-495B-B159-9F9A3AFF8B52 at mainecoon.com>
Content-Type: text/plain; charset=windows-1252
On Feb 13, 2014, at 1:35 PM, David Williams<dave at willomail.co.uk> wrote:
Just managed to score a DG Nova 1210 and need a
little advise & help. The system is pretty basic having only the CPU board, 8k core
memory and another I/O board (Graphic Systems 8400) It does not have any front panel, TTY
or top cover. System is coming from the US to the UK.
Does anybody have a spare front panel or TTY board?
You're looking for a 4010
"basic I/O board". They tend to turn up fairly regularly on ePay in the US; if
you can't find one I'm pretty sure Bruce or I can find a spare.
Thanks.
Might take you up on that offer.
Are there any schematics availiable for this system?
Yes. I don't have a 1200 in my collection and thus haven't bothered to find
prints for the 1200, but I'm pretty sure Bruce has a copy.
Yup, Bruce has
already been in touch :)
Can the PSU be
converted to 240v from 110 or would I need a converter?
Good question. In a 1200,
800, 830 or 840 I'd know the answer to be "yes", but the 820, 1210 and 1220
use an integral power supply that I've never seen in my life. The How To Use and
Abuse manual specifies input as 115 or 230 VAC, 47 to 63 Hz, but it's certainly not
auto sensing -- you'll have to move jumpers.
Yup, did come across some documentation on the 800 which describes
moving some jumpers on the primary transformer for 220/240v operation.
I'm new to
DG hardware and machines of this vintage so is there anything else that I need to be aware
of?
The common traps are failing to understand how the interrupt and data channel
priority and acknowledge lines (intp, inta, dchp, dacha) need to be jumpered around empty
slots and the need in larger chassis to keep a board in the topmost slot if there's
not an external terminator on the I/O bus ) -- otherwise the bus rings like a bell and the
machine will exhibit seriously unwanted behavior.
The 1210 is a baby chassis. CPU goes in slot one, slot two would*typically* get the
basic I/O board (unless you have the 8107 hardware multiply/divide option which needs to
be in slot two) with slots three and four available for memory or I/O. On the 1210 (when
viewed from the back) there's a large edge connector on the backplane that is the
external I/O bus; you may or may not find a terminator sitting on it. Next out from that
(if present) would be a card with three edge connectors; the top most would be the
connector for the factory paper tape reader option, the middle the EIA option and the
bottom the paper tape punch option. The teletype would be a push-on connector on the
backplane, although from the sounds of it you won't have this present on your machine
and you'll need to wire wrap one into place.
Thanks for the info. Clears up a few things about how it all fits together
If you're looking for a discrete paper tape reader
(as opposed to
using the reader on an ASR TTY) you'll need the paper tape reader
option on the basic I/O board, option 4011 (or you'll have to add it
yourself -- it's not hard). You should look for a copy of "How To Use
The Nova Computers". I have a preference for the 1972 (brown-covered
with a photo of a stack of 1200s) version over the 1970 version (white
cover with a photo of a stack consisting of a nova 800, a supernova
and a unicorn, aka supernova SC). It's a good one-stop shop for a lot
of stuff (although you'll still need the prints)
Downloaded a copy and will be
reading it over the next couple of weeks
whie I wait for the machine to arrive.
Welcome to the brotherhood of Edson de Castro
Thanks! :)