Data General NOVA 4/C help

[R SMALLWOOD]

Ok good
               I don't think the heads will load until the floppy disk is turning. 
If its a belt driven drive (most 8" drives were) replace the belt anyway.
I have seen plenty of drives where the belt has become sticky and glued itself
to one of the drive wheels.  It tries to turn and breaks. 
So clean off any residue on the drive wheels.

I am short on DG knowledge but the norm was disk present plus door closed would cause motor start 
either as a drive function or via a CPU interrupt.  


----Original message----
>From : henk.gooijen at hotmail.com
Date : 18/10/2015 - 16:48 (UTC)
To : cctalk at classiccmp.org
Subject : Re: Data General NOVA 4/C help

Thanks Rod,

I feel stupid ... It would have been a simple check to see whether
the floppy drive actually rotates the floppy [dumb, dumb, dumb].
I did transport the disk drive very carefully ... The trip was not
bumpy, and most of it was on a (smooth) highway.
Keeping fingers crossed.

Checking the drive belts is a good idea!  May have fallen off,
I have seen that before on DEC drives (RX01, RX02). Whether the
hard disk has a self test, I don't know (yet).
I have the terminal connected that was used with the system,
a Dasher D200. I am pretty sure that the connection is correct,
but now I start having doubts.

Floppy diskette still OK is the big question. Interesting system,
I need to study the documentation!

greetz,
- Henk


-----Oorspronkelijk bericht----- 
From: Rod Smallwood 
Sent: Saturday, October 17, 2015 11:50 PM 
To: General at classiccmp.org ; Discussion at classiccmp.org:On-Topic Posts 
Subject: Re: Data General NOVA 4/C help 

Whilst I have no experience of DG systems I am familar with drives of 
that era.
The red label is important. If you did not put the shipping locks in we 
must assume it travelled without.
Thats not good. If the journey was not too bumpy then you may be ok.

I have seen floppy drives with shipping locks but its not usual. So the 
floppy drive might be a good place to start.  The drive may be fine but 
disks do not last forever. I would want to be sure the actual disk was ok.


Does it have any kind of power on self test?

As it appears that system does not boot nor do you get any out put on a 
terminal.
(You do have a terminal  attached) perhaps a good  mechanical check of 
the floppy drive.
Things like belts and rubber components are worth a look.

Rod



On 17/10/2015 21:16, Henk Gooijen wrote:
> I picked up the NOVA 4 last Thursday. I had help carrying all the stuff
> (disassembled) downstairs from the attic. At home I had to unload the van
> single-handed. Went well, although I felt my back that evening ...
>
> Today, I cleaned the rack, as all boxes were still on the floor. There
> was little dust, the machine was well taken care of.
> After the cleaning I mounted the hard disk drive on the slides. The hard
> drive is a model 6101-S2 (12.5 MB fixed disk). On the top plate of the
> hard disk is an 8" Qume floppy disk drive mounted. The hard disk and
> the floppy disk form one unit, never seen this construction before!
> The colored twisted-pair flatcable from the floppy drive goes to the
> hard disk and another colored twisted-pair flat cable goes to the
> NOVA 4/C computer, connecting on a paddle board using an edge connector.
>
> See my website: www.pdp-11.nl/dg/nova4/nova4.html
> After everything was connected I applied mains. The fans start to run,
> so far so good. Then I switch on the NOVA and then the hard disk unit.
> The POWER LED on the NOVA and on the hard disk is lit. I can hear the
> hard disk "hum", and when the humming sound stops after a few seconds
> the READY LED is lit.
> However, when I press RESET on the NOVA and then PR.LOAD, the READY LED
> on the disk flashes momentarily (brief), but nothing further happens.
>
> On the disk drive are (behind the panel) two small switches. One has
> the text "NORM" and "PROT", the other has several texts (forgotten),
> but with that switch you can set the hard disk as device 0 and the
> floppy drive device 1, or the hard disk as device 1 and the floppy
> disk as device 0. Basically you can set the boot device, as the machine
> starts from device 0. I have this from the accompanying documentation.
>
> When I put that switch in the other position and press RESET and then
> PR.LOAD on the NOVA, the floppy disk LED is lit for a few seconds,
> but I do not hear a head load ("clunk"), nor head stepping sounds.
> Of course, the floppy drive is loaded with a floppy disk. The label
> on the floppy says "opstart" (Dutch for start up). As the floppy disk
> access LED turn on, I guess that I can say that the NOVA itself is OK.
>
> As far as I know, I have the BERG connector put back on the pins
> where it was before I did the disassembly. That cable connects to the
> terminal. The question might be whether it was on the correct pins
> for starters. I do not get any character(s) on the Dasher D200 terminal
> that came with the system. For that reason, I assume that the terminal
> settings match the settings for the NOVA.
>
> One more remark. On the hard disk is a red label glued. The text on
> it says "remove 2 shipping brackets before operating unit unlock
> pivot arm (see over)". On the rear side of the label is a drawing
> that shows the "front left corner". At the side is a screw (???) to
> lock/unlock the head(s). However, I just don't understand the drawing
> and cannot localize that screw.
> I mailed the previous owner whether he remembers something ...
>
> Anybody has info on the 6101-S2 disk drive? A drawing of those
> shipping rackets, and more info about head locks?
>
> Thanks,
> - Henk