There was a PDP-8 (rack straight 8 with asr33) that was on ebay that
disappeared..anyone know if it was sold? I can't find it, maybe the seller
pulled the auction to sell privately.
Bill
Here's a question for all our Computer Museum curators.
Have any of the old GEAC Library systems ever been salvaged and put into
a museum? They were curious boxes and I think would make a nice addition
to a collection.
bill
Hi all
I re-discovered some eurocards I found in a box at a swapmeet long ago.
It looks like a complete 8085 system. Lots of RAM, 2K EPROM, I/O, FDC.
The strange thing is that the EPROM is mapped at F800, the code in there
looks like 8085 code, and looks like it wants to live at F800. And there's
RAM at 0000.
The DIN41612 A/C 64 pin bus has provision for 16 bits data.
Pics here http://retro.co.za/8085/Microcom/
Anyone maybe have more information on this? I'm curious.
W
I have my faulty VT100 now passing the RAM test, but it is still not
producing any output to the screen. Looking at the DC012 chip it seems to be
permanently asserting the interrupt line and not generating any DMA HOLD
REQUEST signals. It seems that all the clock inputs are running (DOT CLK,
CHAR CLK, VERT RESET). Unless there are other clock inputs not shown on the
schematic, I think this suggests that the DC012 is faulty.
Does anyone know of any other reason why the DC012 might behave this way?
Anyone have a spare DC012 chip?
I have posted a bit more detail here:
https://robs-old-computers.com/2023/10/01/vt100-ram-fault/
Thanks
Rob
Hi Tony and all
>It might have run CP/M (which will run on an 8080, and therefore on an
>8085). That needs RAM at location 0000 [1].
I know of CP/M, I even used CP/M (on my Apple) but I did not know it
needs RAM at 0000. That's kind of strange, since everything that ran
CP/M (OK, everything -80) has vectors at 0. I guess there was a reason
behind it.
I see the CPU board has a jumper "F000/F800" so I guess it does something
to map that address to 0 after reset.
W
I have some open slots in some of my racks. I do have some old DEC
rails, but I have a fair amount of equipment, from both DEC and other
manufacturers, for which those rails are not suitable.
Does anyone have any specific recommendations for shelving? (where
equipment could just be slid on top of, if the equipment isn't too wide
- some pieces are very close to 19 inches all by themselves, and were
designed for front cantilever style mounting.)
Would also be interested in specific recommendations for the following:
DEC VR14 (I have one on a PDP-12 with proper rails, but have another to
mount and don't have proper rails for it)
HP 88780 (Perhaps a shelf is the best bet for these?)
JRJ
Same place as last year in the big parking lot across from Brookdale and
down the street from InfoAge Science and History Museums.
We have Southern Monmouth County Firehouse museum selling food and drinks
in the middle.
This is a fundraiser for both museums (VCF and Firehouse museum) which are
both part of InfoAge.
All the info is here: https://vcfed.org/vcf-swap-meet/
Thanks!
Jeff Brace
VCF National Board Member Chairman & Vice President
Vintage Computer Festival East Showrunner
VCF Mid-Atlantic Event Manager
Vintage Computer Federation is a 501c3 charity
https://vcfed.org/ <http://www.vcfed.org/>
jeffrey(a)vcfed.org
