PiDP11 Kit Build - Part 4 (of 4)

This is the final part of the our series of four videos showing how to build a PiDP-11 kit. The PiDP-11 emulates the experience of running a 1970s mini-computer. The final complete's the build and walks through a basic functional test.
- Part 1 covered the original PDP-11/70 this kit emulates. We'll also start the preparation work for the project.
- Part 2 covered soldering the small passive component and LEDs.
- Part 3 covered the switches and active components.
We reference a number of web pages in this video:
- Getting the kit:
obsolescence.wixsite.com/obso...
- Kit building instructions:
obsolescence.wixsite.com/obso...
- The manual:
www3.ispnet.net/pidp11/PiDP-1...
- The PiDP11 Forum
groups.google.com/forum/#!for...
Check out our other social media accounts:
- Instagram feed at / beigeovision
- Facebook feed at / beigeovision

[@PaulJSchneider]

Excellent tutorial. I bought the kit, bought the pi, read the manual, now I've watched these videos... Time to begin.

[@user-cp9js3dp5f]

OK! I am quite impressed. So, hopefully you will run a new production soon. I will be waiting. In the mean time, I am resurrecting my old 'homebrew' S-100 system I built from scratch. That was 40 years ago! Quite confident that I will be successful. I already started.

[@MotownBatman]

Huzzah! Now I Want one just to Solder the hell outta Everything! Great job!

[@mikekopack6441]

Thanks for doing this series! Going to build mine next Friday.

[@rpk5568]

Being a retired 11/45 tech this caught my eye right away. The 70 is about the same machine, but with the solid state memory installed. Maybe a faster CPU, don't know that. When you use the word emulate does that mean that I can take my 11/45 programming card and toggle in a program? We used to write programs to aid in our repair work. When I started at DEC each test station had a ASR33 teletype. So I wrote a program that allowed my to type on the ASR33 the machine code instead of load address and then one location at a time by setting all the data switches, hit deposit, etc. All the way through to loading the program. With the program I wrote I could just type the code in. While I worked there I saw a unique machine, it was a ruggedized 11/45. Probably designed for a harsh environment. The plastic handled switches were replaced with sealed bat-handled toggle switches. And had a front panel made of a tougher material. That's the only change that stood out in my mind. I'm sure there were other changes. So to get to the point, can I do any programming from the front panel using the PDP 11 instruction set? Probably not, but thought I'd ask. I've got stuff that belongs in one of the computer museums. And I could walk up to a PDP 11/45 that doesn't work and trouble shoot it down the single 7400 series chip. I even have original NOS chips using in these machines. My 11/45 career spanned over twenty years and everything about that machine is trapped in my head. DEC was a fun place to work. Hope everyone enjoys their career as much as I enjoyed mine.

[@beige-o-vision6936]

Short answer, yes. Longer answer, the kit is has a number of preset boot routines you can access from the front panel. These load different emulation configurations. But you can control the emulation directly from the control panel at any time -- including directly keying in programs -> obsolescence.wixsite.com/obsolescence/pidp-11-how-to-use. If this is a standard config you want to use can also change one of the available emulations to include on that runs the emulated machine up to a halted state with some arbitrary emulated peripheral configuration. For detailed information and Q&A you can use the kit producer's forum here -> groups.google.com/g/pidp-11.

[@paulthompson1988]

Thanks for your tutorial. A very informative 4 videos.

[@beige-o-vision6936]

Glad it was helpful!

[@RyanMcDonald]

Looks like a cat hair magnet to me! :)

[@beige-o-vision6936]

Mount on the wall above kitty level. Only take down when in use. When in doubt, become so use to cat hair on everything, you can no longer really see it -- a kind of dirt blindness.

[@booboyBL]

Thanks for this. I'm waiting for Oscar's next production batch, and then I will be ordering one of these. The Pi is already set up with the software, so I'm raring to go! I have already had his earlier PiDP8/i up and running for some time now, so I'm looking for another kit to build. This looks a lot more professional than the PiDP8 kit. TBH, I probably get almost as much satisfaction from the build process, as I do from actually using the machine.

[@ChristopherCobra]

Thanks - looks like I will finish this project (just soldering the last switches). Not sure I would have gotten this far without your videos. If you want suggestions on others, let me know! I'm hoping I can get an OS that I can compile DECwar on and get it running. I also an coming up with a rack mount case (I hope).

[@meneerjansen00]

This thing is friggin' cool!

[@kevinmurrell9779]

I really must build mine! BTW there is an 'l' in soldering!

[@EricJung1]

How long would you guess the entire project took to build?

[@beige-o-vision6936]

It's a good question. Most people do these in fits and starts. We did this one in about four to five hours cumulative. But I imagine you could do it in half that.

[@jq747]

Now to install RSTS-11 :)

[@680x0]

I noticed some empty chip sockets labeled max232 (RS-232 interface chips)... does this mean there is an option (perhaps being worked on?) for connecting a real serial terminal or something?

[@beige-o-vision6936]

The board's meant to be hackable. So there's an open expansion area, and a specific RS-232 expansion option. You can find a discussion of the possibilities here: obsolescence.wixsite.com/obsolescence/pidp-11-connectivity-options