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RolexTM
February 13th, 2013, 01:05 AM
We recently discovered a Data General Nova computer in our local computer musuem...standing forgotten
in a dark corner of a storeroom. After replacing some of the broken input switches it seems to execute our super advanced test program

1: jmp 2
2: jmp 1

fine ;)

We have absolutely no peripherals (discs, terminals, tapes whatever) - just the bare machine.
It has 2 memory cards in it, one CPU and two other boards without description on it (if i remember right)

It's time now to test the terminal funnction. I wrote a simple test program with the dga cross assembler
that at least runs fine on the simulator.

If the machine turns out to be usable or at least repairable we might try to emulate a tape or
even disk and run one of the os-es. From my slight unterstanding the machine is a simple nova, it does
not have the program load option. I still fail to understand the disc channel DMA functions properly,
even if it looks very basic ;)

If anyone has infos on what to do next, what to try or check please chime in. I already sighted most
of the software and documentation of bitsavers and simh which is luckily very complete.

We might also "dump" out the core memory once the terminal is working. Just curious if theres anything
of interest left inside ;)

Will keep you posted with pictures of the actual machine on thursday.

Chuck(G)
February 13th, 2013, 09:12 AM
You're probably more likely to turn up people who know these systems intimately on the the classic computer list (subscribe at http://classiccmp.org.)

dave_m
February 13th, 2013, 09:51 AM
That's probably true but I hope RolexTM keeps us posted here also as I have a soft spot for the NOVA computers.

Doug G
February 14th, 2013, 02:45 PM
Is it a Nova, or Nova 2 or Nova 3? I used to service some Nova 2 and clones years ago but never got in to any coding. My recollection is the system I maintained had an external System Industries disk controller and I think a CDC Hawk or maybe SMD drive, and a Hazeltine terminal as the console terminal.

RolexTM
February 14th, 2013, 02:52 PM
1186311864118651186611867

RolexTM
February 14th, 2013, 02:58 PM
11868118691187011871

Sorry, i am currently posting from the phone

It is a Standard Nova. I guess.


Problem is the ACs dont work. There are
Lots of Bits Stuck on 1 as you can See
In the picture. Its the Same Pattern for
All ACs. Will Report back later when i am
At the pc.

Qbus
February 22nd, 2013, 04:20 AM
That looks like a great little system, appears to only have four registers (AC0 to AC3) but like the small size. Imagine the Nova three and four were more advanced. Any idea on when it was built?

RolexTM
February 25th, 2013, 06:03 AM
The boards say Copyright 1968...... Pretty old.

dave_m
February 25th, 2013, 08:21 AM
It may be a NOVA 1200, a fairly early version of the NOVA minicomputer: NOVA (http://users.rcn.com/crfriend/museum/misc/NovaCon.html)

Be careful with your little test program. As I recall from NOVA school, a jump to zero running at location zero will overheat the system if left running to long. The OP Code for a direct JUMP to location zero is octal 00000.
-Dave

RolexTM
February 26th, 2013, 02:24 AM
Yeah, we already put in some test programs and repaired the AC error. Next step is trying to get our hello world
to run..... and the memory voltage distribution board that is subject to overheat failure is already repaired and was repaired
at least once before because of a semi desastrous failure where the board is more black than brown....

Marty
June 19th, 2014, 11:20 AM
Hi All;
Dave-M, its NOT a Nova 1200.. Its a plain Nova.. It looks like some-one did some modification on it, from looking at the picture of the Back..
THANK YOU Marty