On Nov 28 2004, 7:50, Lyle Bickley wrote:
> My Onyx is linked to a Sun NFS/DNS server which unfortunately has a
SAS FDDI
> device - so my FDDI setup does not make a proper ring either.
Sigh...
>
> I'm on the lookout for a FDDI switch with both dual and single
capability -
> but so far haven't stumbled across one for a price I'm willing to
pay...
If I find anything, I'll let you know. I was disgusted to discover, a
couple of years ago, that our Chemistry Department threw out several
nice FDDI switches about a year or two previously, because they thought
nobody would want FDDI any more :-( This statement came from the guy
who gave me my first Indigo (and a few other machines, at other times)!
--
Pete Peter Turnbull
Network Manager
University of York
I've got an HP Paintjet printer on the bench (this is on-topic, it seems
to have been made in 1986 or so). I've figured out most of it (even the
PSU section with a complex custom DIL resistor pack), but I can't
indentify the driver chip for the linefeed motor, which is a 4-input
unipolar stepper motor.
Anyway, the driver chip is marked 1820-4864 (too late for my equivalents
list). It would seem to be a quad power driver chip rather than a stepprr
motor controller, as it takes in 4 bits from one of the microocntroller
ports. The pins, as I've traced them seem to be :
1 Input
2 +5V
3 Output
4 N/C
5 Input
6 +5V
7 Output
8 Ground
9 Clamp
10 Output
11 Input
12 +5V
13 Output
14 Input
15 +5V
16 +5V
It's a normal 16 pin DIL package (no heatsink tabs or anything).
I usspect, without prood, that it's actually 4 separate stages, AND or
NAND functionality, : 1 & 2 -> 3, 5 * 6 -> 7, 12 & 11 -> 10, 15 & 14 -> 13
Does that pinout ring any bells with anyone? It's not any of the chips in
my TI Interface Databook..
-tony
On Nov 28 2004, 14:31, Gordon JC Pearce wrote:
> Pete Turnbull wrote:
> > Our library announced they had some to get rid of a few days ago.
If
> > it's not been claimed I could get you some, but the boxes are heavy
so
> > expect to pay quite a lot for shipping.
> >
> Can you get me the postcode? One of my mates runs up and down to
> Birmingham every week and can probably be persuaded to make a detour.
> Especially since I'm doing his wheelbearings for him next weekend...
It would be a sizeable detour, from Brimingham to York. The postcode
is YO10 5DD, and if he has satnav, he'd be looking for Grid Ref SE 622
506 or 53? 56.9' north (53.9477?), 1? 3.1' west (-1.0523?).
--
Pete Peter Turnbull
Network Manager
University of York
Rich,
I have a Synertek SY6545 CRT Controller applications note (AN3 July 1980).
It is about 24 pages, I can scan it tomorrow.
Michael Holley
www.swtpc.com/mholley
>
> Someone contacted me and asked if I had ever seen an "application
> notes" document for the MOS 6545 CRT controller chip. I don't have it; all
> that I have is the data sheet.
>
> If anyone has this, please let me know. Thanks.
>
> Rich
>
On Nov 27 2004, 18:54, Dave Dunfield wrote:
> At 16:28 27/11/2004 -0500, you wrote:
> >----- Original Message -----
> >From: Tony Duell <ard(a)p850ug1.demon.co.uk>
> >
> >> What's this love of the ZX81, which I regard as a postively
horrible
> >> machine. I'd not rip one apart, though, mainly because there's
little of
> >> use to raid from it...
> >
> >You regard it as horrible because . . . ?
>
> Aside from keyboard ;-)
>
> CPU intensive video design - lose video when program running (or
SSLLOOWW
> mode for ZX81).
>
> This also makes it highly dependant on the internal firmware, so that
it's
> tough to adapt other Z80 software systems to run on it.
>
> "RF only", and poorly shielded computer make it tough to get decent
TV display.
I wonder if that's becasue it's VHF? UHF ones I've seen here aren't
*too* bad, and it's trivial to add a composite video lead.
> Limited internal RAM - and expansion very prone to connector
problems/flakiness
> (practically useless without an external keyboard so that you didn't
have to
> touch the machine while it was running).
Yu can replace the internal RAM.
> Slightly odd dialect of BASIC.
Slightly?!*!
> But... I still consider the ZX80/81 a rather interesting and
innovative design,
> because it truly was designed to get "something from almost nothing".
Most of
> the items listed above are just the "nature of the beast" - given
what it was
> (the lowest price entry on the block) and to be *VERY* cheap to
manufacture.
Yes, I would agree. I still keep mine, though I've hardly ever used
it.
--
Pete Peter Turnbull
Network Manager
University of York
Hi:
Someone contacted me and asked if I had ever seen an "application
notes" document for the MOS 6545 CRT controller chip. I don't have it; all
that I have is the data sheet.
If anyone has this, please let me know. Thanks.
Rich
Rich Cini
Collector of classic computers
Build Master for the Altair32 Emulation Project
Web site: http://highgate.comm.sfu.ca/~rcini/classiccmp/
/************************************************************/
On Nov 27 2004, 13:01, Lyle Bickley wrote:
> I always have tried to collect/restore those systems with the best
graphics
> and video options...
>
> In my SGI collection I have:
>
> Qty. Description
That's a nice collection, especially the second Onyx. FDDI, too (I
have FDDI on my Origin and two Indys and an FDDI-ATM bridge but
unfortunately the Indys are SAS devices so it doesn't make a proper
ring).
--
Pete Peter Turnbull
Network Manager
University of York
Free for postage a bunch of unused Centronics ribbons for the models 400,
455, 800, 855. Reorder number on the box is 44688116
Stefan.
-------------------------------------------------------
http://www.oldcomputercollection.com
On Nov 27 2004, 10:59, Gordon JC Pearce wrote:
> I apologise if this question has been done to death, but is there
> anywhere in the UK I can get 14 7/8" greenbar paper?
Our library announced they had some to get rid of a few days ago. If
it's not been claimed I could get you some, but the boxes are heavy so
expect to pay quite a lot for shipping.
--
Pete Peter Turnbull
Network Manager
University of York
