At 09:14 AM 3/11/2018 -0500, Adrian Stoness wrote:
>get some thick plexi glass to cover it and sit it up for display to look in but not touch ;)
Good idea! And easy to add to the simple base frame I had in mind. Zero changes to the machine.
I was too stuck in modern fast digital thinking - 'RF-tight metal case' etc.
Ha ha, on reflection I don't think so.
Guy
At 11:40 PM 2/11/2018 -0500, you wrote:
>still supper clean id love to have that even
I know how you feel. I've never had _any_ possibility of finding an old PDP machine before. Very happy to have this one.
Re dirt - actually it's pretty grimy. I did a preliminary dust off for the pics, but later it will get a
complete cleaning. After I have docs on where all the flip chips should be, and I figure out a non-marking way to
record which ones were in which slots, as I remove them to clean each one and the backplane.
With precious museum pieces like this, you DON'T write numbers on them in marker pen.
Just doing a quick eval now, since I'm already ridiculously stack-pushed with multiple other projects.
Highest priority: Make a mechanical guard for the wired backplane pins. As it is now, just putting the machine
down on a desk wrong could do major damage.
Have to do this before I even pack it away in the box again. It's just been *really* lucky so far, with only minor pin bending despite inadequate packing.
Guy
For those interested in Rolm / Data General Nova Minicomputers I have
scanned the hard-to-find Rolm Corp Rugged Nova 1601 brochure from 1970. I
also scanned what price and module docs I have and uploaded them all here:
https://www.vintagecomputer.net/ROLM/1601/
I don't believe this has been uploaded by anyone yet.
Bill
>the i860 found at least a little niche on graphics boards, so somehow
>not a complete failure ;-)
I'd be mildly surprised if Intel ever made enough from selling i860s
as GPUs to cover the cost of developing and marketing them. At the
time, Intel was pushing them as their RISC processor, and put a lot
into the program. Going to take over the world and all that. Maybe
not a 'complete' failure...just mostly.
From: Chuck Guzis <cclist at sydex.com>
>On 10/26/18 6:10 AM, Gordon Henderson via cctalk wrote:
>
>> However it was a royal PITA to code for although a 32-bit CPU, it would
>> read memory 64 bits at a time (actually 128 IIRC to satisfy the cache),
>> with half that 64-bit word being an instruction for the integer unit and
>> half for the floating point unit, so you effectively had to build a
>> floating point pipeline by hand coded instructions, so 8 (I think)
>> instructions to load the pipeline, then each subsequent instruction
>> would feed another value into the pipe, then another 8 at the end to
>> empty it. Great for big matrix operations, rubbish for a single add of 2
>> FP numbers.
>
>My impression of the i860 was that it might have been fun for about 2
>weeks for which to code assembly, but after that, you'd really start
>looking hard for an HLL to do the dirty work for you. While there's a
>sense of accomplishment over looking at a page of painfully
>hand-optimized code that manages to keep everything busy with no
>"bubbles", you begin to wonder if there isn't a better way to spend your
>life.
It wasn't fun for the whole 2 weeks. And the i860 is Yet Another
example of Intel claiming their compilers were going to be so smart
that all the architectural complexity/warts will never be noticed.
Wrong, and they didn't learn and said the same thing about Itanium.
The interrupt stall issue that Gordon pointed out was so bad they were
basically relegated to single-task software in the end.
KJ
Hi,
Most of the documentation is found here:
http://www.bitsavers.org/pdf/dec/pdp8/pdp8a/
For some basic testing look here:
http://www.bitsavers.org/pdf/dec/pdp8/pdp8a/EK-8A001-OP-002_PDP-8A_Operator…
in chapter 5.1 (pdf page number 48).
To do basic memory read and write:
Press MD and DISP (memory data register will be displayed on the four digits)
Then press 0200 and LA (load address)
Press 5050 and D-THIS (deposit to memory on this adress, no increment).
Press E-THIS (examine on this memory address, no increment) and you should
get the same result back.
Another good place to be is to post in the DEC category on the VCFED
forum: http://www.vcfed.org/forum/forumdisplay.php?23-DEC
Good luck!
/Anders
> Date: Fri, 02 Nov 2018 08:56:08 -0700
> From: Columbia Valley Maker Space <info at cvmakerspace.ca>
> To: cctalk at classiccmp.org
> Subject: PDP8/a Initial Power Up
> Message-ID: <27c485c4ae4ef3a32a0756739e85c28b at cvmakerspace.ca>
> Content-Type: text/plain; charset=US-ASCII
>
> Hello everyone - my first post, so be easy on me!
>
> I have just acquired a PDP8/a and a Remex punch tape reader. The unit
> starts up and displays some data on the displays, and that is about all
> I can tell you.
>
> I am going to do some googling about this, but I am looking for basic
> initial tests .... something I can enter via the keypad.
>
> I learnt some basic programming in 1978 on a PDP8, but that was the last
> time I touched one, so if you are going to suggest some tests, I need
> complete instructions. I don't know how to modify a memory location, let
> alone enter and check a program. I will pick all this back up very
> quickly and I do use computers in my work a lot - I am also an
> electronic hobby guy and have been for years. My point is I am OK with
> component level measurements, I have a scope and probes, etc.
>
> So there you go - hope to hear back form you guys.
>
> Cheers,
>
> Brian
>
> --
> Brian McIntosh
> Columbia Valley Maker Space Communications Guy
> info at cvmakerspace.ca
> 250 270 0689
>
> Date: Fri, 02 Nov 2018 08:56:08 -0700
> From: Columbia Valley Maker Space <info at cvmakerspace.ca>
> Subject: PDP8/a Initial Power Up
>
> Hello everyone - my first post, so be easy on me!
>
> I have just acquired a PDP8/a and a Remex punch tape reader. The unit
> starts up and displays some data on the displays, and that is about all
> I can tell you.
>
> I am going to do some googling about this, but I am looking for basic
> initial tests .... something I can enter via the keypad.
>
> I learnt some basic programming in 1978 on a PDP8, but that was the last
> time I touched one, so if you are going to suggest some tests, I need
> complete instructions. I don't know how to modify a memory location, let
> alone enter and check a program. I will pick all this back up very
> quickly and I do use computers in my work a lot - I am also an
> electronic hobby guy and have been for years. My point is I am OK with
> component level measurements, I have a scope and probes, etc.
>
> So there you go - hope to hear back form you guys.
>
> Cheers,
>
> Brian
>
> --
> Brian McIntosh
> Columbia Valley Maker Space Communications Guy
> info at cvmakerspace.ca
> 250 270 0689
>
Try the toggle-in tests that are here:
https://www.pdp8online.com/pdp8cgi/query_docs/tifftopdf.pl/pdp8docs/toggle_…
--
Michael Thompson
Hello everyone - my first post, so be easy on me!
I have just acquired a PDP8/a and a Remex punch tape reader. The unit
starts up and displays some data on the displays, and that is about all
I can tell you.
I am going to do some googling about this, but I am looking for basic
initial tests .... something I can enter via the keypad.
I learnt some basic programming in 1978 on a PDP8, but that was the last
time I touched one, so if you are going to suggest some tests, I need
complete instructions. I don't know how to modify a memory location, let
alone enter and check a program. I will pick all this back up very
quickly and I do use computers in my work a lot - I am also an
electronic hobby guy and have been for years. My point is I am OK with
component level measurements, I have a scope and probes, etc.
So there you go - hope to hear back form you guys.
Cheers,
Brian
--
Brian McIntosh
Columbia Valley Maker Space Communications Guy
info at cvmakerspace.ca
250 270 0689
> From: Columbia Valley Maker Space
> The unit starts up and displays some data on the displays
You're lucky that worked. Old power supplies need to be brought back to
life in stages.
> something I can enter via the keypad. ... if you are going to suggest
> some tests, I need complete instructions. I don't know how to modify a
> memory location, let alone enter and check a program.
Find all the PDP-8/A documentation online that you can (e.g. Bitsavers) and
download and read it; that will cover how to use the front panel.
Noel
