While I don't know if this is actually useful information
as I have not attempted to build any (yet), but this site
has information on a replacement G888 board:
If anyone gets around to making some of the these before I
do, please let me know. I would be interested in the results
and some bare boards.
--tom
On 5/18/14, 3:05 PM, Ian S. King wrote:
Date: Sat, 17 May 2014 18:38:02 +0200
From: Marco Rauhut <marco at familie-rauhut.eu>
To: General Discussion: On-Topic and Off-Topic Posts
<cctalk at classiccmp.org>
Subject: Re: DEC TU56 dual drive and it's modules
Message-ID: <5377906A.8060909 at familie-rauhut.eu>
Content-Type: text/plain; charset=ISO-8859-15; format=flowed
The tip with the look on the wiering of the backplane bring "light" into
the darknes.
Now the most Modules in right placees....
Only two module places left for confirmation.
Thanks to all so much!
Am 16.05.2014 22:33, schrieb Tony Duell:
> In the engeneering drawings "Module
Utilization" are shown special
> places for each module. In my drive the Modules on different places then
> in the drawing.
> Is the backplane a real bussystem or got i use the ports shown in
drawings?
The T56 is most definitely not a bused backplane, the modules have to be
in the right slots.
I think exacltly which modules you need depeends on the controlleryou are
uisng it with. So you might need ot check that.
And DEC often drew the modual utilisation diagram looking a the _wiring_
side of the backpl;ane, not at the modules. It's a mirror image of what
you might expect.
-tony
This may have been mentioned and I missed it, but just in case: if the
drive unit was connected to a TCxx (typically a TC08) then it will not have
the G888s in its backplane. I believe you stated you want to connect this
to a TD8E, in which case you need the G888s. I'm sorry to say, they are
quite hard to find and when you do find them (quantity 5), you will pay
dearly for them. That's been my experience - I have a TU56 that's been
languishing while I try to locate G888s for less than a mortgage payment.
Also, in case you haven't noticed this already: the TU56 has an internal
power supply that runs the motors and some of the control circuits, but
also requires an external supply for the logic. -- Ian