Available Omnibus options and accessories

[ftcnet]

Here's a list of current DEC PDP-8 Omnibus family (8A,E,F,M) compatible hardware sources that may be of interest. Instead of waiting for the item you need to show up on eBay, check this list. Some items may be 'in-stock', but most of them assume you know how (or are willing to learn how) to submit the PCB files to a vendor, source your parts, construct (and debug) it yourself.


32KW RAM board for Omnibus - based on the Stefan Lafferty design


MI8-E M847-extended-version-V1.1 - allows selection of 15 different boot or test programs from SW switch


32K Memory+Bootstraps for Omnibus - above two (32K & MI8-E) boards combined on one quad board


DK8EA M882 AC Real Time Clock - no DEC or SP chips used. Only 74xx and 74HCTxx series chips

- works with RX01/RX02 emulator as well as DEC drives
RX8E M8357 RX01 / RX02 floppy controller - no DEC or SP chips. Only 74xx and 74HCTxx series chips are used


TA8E M8331 TU60 decassette controller - no DEC or SP chips used. Only 74xx and 74HCTxx series chips


VC8E M869 Point Plot Controller - no DEC or SP chips used. Only 74xx and 74HCTxx series chips (works w/ M885)


VC8E M885 Point Plot D/A converter - no DEC or SP chips used. Only 74xx and 74HCTxx series chips (works w/ M869)


Omnibus - USB interface - High-speed KL8-E compatible serial I/O (with enhanced instruction set)

Please let me know of available Omnibus compatible (quad or hex) boards that I could add to this list (or any corrections).

 

[ftcnet]

--- Here's some items that are helpful when debuging or troubleshooting DEC modules

- all standard DEC FlipChip sizes + extended length versions
DEC Flip-Chip Extender boards - used for component-level circuit troubleshooting (Todd Goodman may have stock)

- PCB only, for staggered pins
DEC H851 top connector PCB - used on CPU, memory, controllers (uses DEC-style connectors)

- PCB only, for in-line pins
DEC H851 top connector PCB - used on CPU, memory, controllers (uses ECS-style connectors) shouldn't be too hard

Digital PDP8 ECS H851 debug tool - make your own BC08M-0M replacements using ECS connectors and 40p ribbon cable


The Glitchwrks proto board or the Douglas Electronics proto boards are still available.

--- Here's a low-cost, high-speed, mass storage peripheral (saves wear and tear on drives and media)

​- Don North AK6DN may have stock
RX01 / RX02 emulator - works with Arduino Mega2560 processor board, uses MicroSD storage

​
RX01 / RX02 emulator - Roland Huisman 2-layer version

--- Here's some miscellaneous parts that are often needed for repairs

​
PDP-8 Panel Switch Toggle or PDP-8 replacement paddle switch handle (these work for the PDP 11/20 also)

​
DEC H960 rack fascia panel clip
Vince Slyngstad's SoMuchStuff website has quite a few .STL files for (mostly PDP8-related) 3D printable items


The original PDP8/E DEC-spec Oshino OL-2 front-panel indicator bulbs are available from:
Surplus Sales of Nebraska or see: PDP-8/E Front Panel Lamps for discussion on compatible replacements.
[]​

 

[BitWiz]

Douglas Electronics has several Omnibus/Unibus related boards:

http://www.douglas.com/index.php/25-de-8.html
http://www.douglas.com/index.php/11-de-8.html
http://www.douglas.com/index.php/10-de-8.html
http://www.douglas.com/index.php/11-de-hex.html
http://www.douglas.com/index.php/19-de-8.html
http://www.douglas.com/index.php/6-de-8.html
http://www.douglas.com/index.php/12-de-8.html
http://www.douglas.com/index.php/28-de-8.html
http://www.douglas.com/index.php/26-de-8.html

 

[antiquekid3]

I don't have a great photo of it at the moment, but an effort between Malcolm Macleod and Alan Hightower (and Vince Slyngstad as well, perhaps?) produced a single-CPLD serial card 4 years ago which has proved most reliable for SerialDisk operating at 230.4k baud. The fact that this ATF1508 CPLD can sit on the Omnibus directly with no other transceivers makes it very attractive for future designs of other boards.

Kyle

 

[BitWiz]

I've seen this card while looking at PDP-8 stuff on the bed. I was trying to find it to mention also. I am interested in buying one of those cards if anyone has one with the CPLD soldered on.

 

[antiquekid3]

I've seen this card while looking at PDP-8 stuff on the bed. I was trying to find it to mention also. I am interested in buying one of those cards if anyone has one with the CPLD soldered on.

If you're talking about the ATF1508 card, the CPLD is socketed in a through-hole socket. Vince and others have often pushed for non-SMD components for the boards (though Vince knows I have my own thoughts about that!).

The high-speed USB serial card that Philipp Hachtmann made is indeed an almost entirely SMD layout.

 

[BitWiz]

Yes I was talking about the one with the socketed CPLD.

I would be interested in any high speed card. Right now I'm waiting for the 14.7456MHz crystal I ordered to make my second M8650 run at 115,200 baud.

If I design a board (i have several in mind) I would weigh the cost of using SMD and thru hole components with sockets.

I have a working relationship with an contract board assembly/manufacturing house that is like 10 minutes from my house.

I'm even thinking of ordering like 10 or 20 of each of Roland's boards and having them assemble them (without sockets) even though they are through hole.

Another option would be to re-lay them out for SMD parts. But my layout skills are not very good. The last time I laid out a board it was using plastic tape on sheets of Mylar at 4 to 1.:-D

 

[Roland Huisman]

Maybe good to mention the M993 clone too. You need that board with the RK8E controller
or the Plessey RK8E controller clone to be able to connect a RK05 to the controller.



M993 connector board

(I think I still have a few boards left)

 

[ftcnet]

Is this the ATF1508 Omnibus USB interface we're discussing? Are PCB's or Gerber files available? I don't see any at: https://github.com/malmacleod/omni-serial
Did the issues mentioned by Hachtmann get resolved? If it's a 'code only' project, then it's not really an 'available' option.

 

[vrs42]

Is this the ATF1508 Omnibus USB interface we're discussing? Are PCB's or Gerber files available? I don't see any at: https://github.com/malmacleod/omni-serial
Did the issues mentioned by Hachtmann get resolved? If it's a 'code only' project, then it's not really an 'available' option.

Yes, I think that's the one. The Eagle board (and schematic) files are still up at https://www.retrotronics.org/svn/omniserial/. I also have a copy in the SVN database that backs www.so-much-stuff.com, though the links are currently set not to propogate to the "boards" section of the website.

Rereading Phil's complaint, I still mostly see him complaining that the wheel had been reinvented. I don't know all the resources Mal drew upon to create his code, but since his day job is as an IP lawer in Australia, I really can't believe that Phil's code had anything to do with it.

Vince

 

[BitWiz]

There are two different boards.

One is Phillips Hachtmann's Omni-USB which emulates a M8650 with a USB B connector ( http://pdp8.hachti.de/projects/omni_usb/ ).

The other is Malcolm Macleod and Alan Hightower's Omni-Serial which is a Omnibus to Serial Implementation. I cannot find the website for that but I have attach the design files to this message.

 

[ftcnet]

Looks like Paul Lennous is making good progress on re-creating drop-in replacement, compatible KK8-E CPU modules (and H9194-style backplane).

M8310
.

M8320
.

M8300
.
I get the impression he's working on the M8330 now and will make the Gerbers available when he's had a chance to test them.

 

[Roland Huisman]

Nice! Soon we can build complete PDP8 machines from all new parts.

 

[jdreesen]

...except for the motherboard connectors.....I need to create a new motherboard for my Lilith, that uses the same style 1.25" spaced connectors.

 

[Roland Huisman]

Te ECS connectors work fine, when you watch the link you see also a dwaring for a backplane. Since the pins are inline I think he is using the ECS connectors too.

 

[thunter0512]

Nice! Soon we can build complete PDP8 machines from all new parts.

That would be a dream come through.

 

[MauriceH]

What a great work to redesign these old PDP8 PCBs. As I also made a Roland M847E card and the AK6DN RX02 EMU its really fantastic how those boards look when ordered. The quality is intense high. The effort made to the work around obsolete TTLs.