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regnevacs
December 23rd, 2010, 03:20 PM
Hello All: Does anyone have a PDP 8A Programming console available or an alternative?
I have everything else but this one last piece. contact andyprigge@gmail.com
Merry Christmas Everyone................................

Lou - N2MIY
December 24th, 2010, 05:10 AM
I am in a similar situation. I have a pile of bits to build an 8/a, but no operator or programmer console. I have decided that when I get around to that project, I will build up a work-alike of the operator's console from the print set (the simple power / boot / halt switch panel, not the cheesy keypad / LED switch register.) I did that very thing for an 11/04 that I built from parts and it did come out nicely.

Since there are not many pdp-8 people on here, I'm wondering where you are in the world and what other perhiperals you plan on putting on that omnibus 8. Do you intend to run OS/8?

We run an 8/e with TA8E and non-dec RX28 here as well as various HD6120 based decmates.

Lou

vrs42
December 25th, 2010, 06:20 AM
I have PCB assemblies for a clone of the Programmer's Console, but not for the Operator's Console. You can't power up without at least an Operator's Console. (Fortunately, the Operator's Console is a fairly simple beast.)

Note that the expensive part of the Programmer's Console isn't just the electronics.
There is also a pretty front panel to be made, with holes for the LED displays, the
keypad buttons, lettering, etc.

Vince

Crawford
December 26th, 2010, 08:03 AM
If by the programmer's console you mean the pushbuttons + LED's for the front, I have the board stack (but not the aluminum frame). I got this before I bought my 8/a from Tim R. I tried the console out on my functioning 8/a and IIRC it did not work, and having no motivation to troubleshoot it, went back to the spares box. I also have the odd 12-bit console that may have been an 8/e clone console from Nuclear Data. (I guess I had some delusions of building machines from front-to-back ?:-)

Seems quite odd that you can't run the 8/a 'console-less', as it should have all it needs to boot from disk..

-Crawford

vrs42
December 26th, 2010, 09:33 AM
If by the programmer's console you mean the pushbuttons + LED's for the front, I have the board stack (but not the aluminum frame).

Yes, by "programmer's console", I mean the pushbuttons and LEDs, used to examine
and modify memory, examine registers, etc.


Seems quite odd that you can't run the 8/a 'console-less', as it should have all it needs to boot from disk..

-Crawford

You can run without the programmer's panel, but the operator's panel has the
"power" and "boot" switches on it. It will boot from disk if you toggle the "boot"
switch on the operator's panel.

Vince

Lou - N2MIY
December 26th, 2010, 02:46 PM
Vince,

I will have to check the "stuff" for the 8/a console boards. Did you ever have them run and assemble them? Depending on how complicated it looks, I might wire wrap it.

I have thought hard about some of the other "stuff". Your RX8E is tempting, because I have yet to find one, dead or alive. I still use a DSD440, but have a real RX02 mounted in the rack above the 8/e, waiting for me to wrap an RX8E for it.

Your work is quite impressive and I'm glad you have shared it.

Lou

vrs42
December 26th, 2010, 04:18 PM
Vince,

I will have to check the "stuff" for the 8/a console boards. Did you ever have them run and assemble them? Depending on how complicated it looks, I might wire wrap it.

I built one up, but didn't debug mine because I bought the "real thing". Charles
M. did build one, though, and he got his to work. There are some minor problems
with the boards are they were ordered. The power distribution isn't all it should be,
so you want to route power in parallel with the existing power traces to keep the
resonances down. Also the DEC drawings mislabel the pins on one of the
connectors, and I can't recall offhand if that is fixed on the boards or not.
(I do have the wiring changes, but I haven't looked up what is etched into the
boards.)

Anyway, they do work, with a little fiddling.


I have thought hard about some of the other "stuff". Your RX8E is tempting, because I have yet to find one, dead or alive. I still use a DSD440, but have a real RX02 mounted in the rack above the 8/e, waiting for me to wrap an RX8E for it.

Your work is quite impressive and I'm glad you have shared it.

Lou
Thanks!

The RX8E is full of unobtainium chips. You might want to go with the Posibus
adaptation, as that uses more easily obtained components. OTOH, neither Ethan
nor I have our prototypes for the Posibus version debugged yet :-(. (I'm
currently being distracted by a TD8E cable replacement project with Jack R.)

Vince

Lou - N2MIY
December 26th, 2010, 04:36 PM
I could actually do a posibus RX8 interface. For no good reason, I do actually have an M8350 posibus adapter!

As for the unobtanium RX8E parts, I have just about everything, between what's already in the parts boxes and lots of other parts boards (non-dec, don't worry!)

I will look around the "stuff" for the posibus RX8 project details.

Lou