Building Instructions for the PiDP-1 Kit

To Part 2:
Building the Rack

Building the PiDP-1 should take about 20 minutes to make the case, then about 4 hours soldering up the PCB boards. The Rack version takes about 3 hours extra.
Tools required: Soldering iron, side cutter, Phillips screwdriver.

  • If you hit upon a problem, or have questions when building the kit:
    • Software install or soldering problems: oscar@ceds.dev (read by Jose and Oscar these days) is the first responder email address. Email both of us for the fastest response :-) We're pretty good at remote diagnosis, if you allow some time debugging with us, we'll get your machine going for sure.
    • Spare parts: contact Jose (j.leon@ceds.dev). Operated on a trust basis: if you feel it's our fault (missing parts? That Never Happens™) the parts are free. Otherwise, we ask you for shipping and the cost of the parts.

What you need to know before you start

A. There are two versions of the PiDP-1 kit:
  • Console version: the PDP-1 front panel in a stand-alone case
  • Rack version: contains the Console version plus the extra parts to make the rack. Rack version owners thus have two cases for their PiDP-1.
    Move the PiDP-1 circuit boards from the rack to the console case when you want the PiDP-1 to travel with you :-)
Differences between the Console and Rack PiDP-1s

Both versions are identical electronically, and in operation. But:

  • The Rack version adds Blinkenlights on its I/O panel. Useful as you can see the bit patterns of key presses and paper tape data flow by.
  • The Rack version comes with two built-in USB connectors, located in the black slit of the Paper Tape panel. The top connector acts as paper tape reader, the bottom one as the paper tape punch. Just consider USB sticks to be fancy paper tape rolls; their contents are visualised on screen as well. These USB connectors are not necessary, because you can comfortably mount paper tape image files stored on the Pi's SD card just as well. This feature is intended for demonstrating (semi) authentic PDP-1 operation with inserting paper tapes. Instead of 'clinically' selecting a paper tape image file off the SD card.
  • Lastly, the Speaker panel has 4 speaker slots. Stereo sound from the PiDP-1 comes from the outer two slots. An optional, standard 7" HDMI display can be fitted behind the middle two speaker slots. One to show the paper tape contents whizz by, the other for a small Type30 display. This allows you to have the PiDP-1 Rack version as a stand-alone unit without cabling hassle. Just add a Bluetooth keyboard.


B. You can clip on blue or white front panels.
But - you'll notice that the kit contains 3 nearly identical front panel sets:
  • Ottopanel: White, named after the inventor. Becomes part of the case.
  • blue and white clip-on front panels. Swap them to change colours. DEC could never make up its mind, so why should you?


Console & Rack version, blue & white

Parts Lists

Parts List - PiDP-1 Console version

PiDP-1 Console PCB Parts:

PiDP-1 Circuit boards:

PiDP-1 Spacewar game controllers:

PiDP-1 Small Parts:

  • (To the left:)
    17 PCB panels in total
  • Switches and LEDs:
    • 44 Small Toggle Switches + nuts
    • 8 Large Momentary Switches + nuts
    • 16 extra nuts for Momentary switches
    • 119 LEDs + LED spacers
    • 55 diodes, 1N4148
    • 18 Resistors, 680 ohm
    • 4 Resistors, 510 ohm
  • ICs:
    • 74HC138 IC + chip socket (U2 on PCB)
    • 74HC238 IC + chip socket (U1 on PCB)
    • UDN2981 or TBD62783 IC + chip socket (P1)
  • Connectors:
    • DE-9 Female connector
    • 1*11 pin header, straight + 1*11 pin header, angled
    • 11-strand rainbow connector cable, F/F
  • Raspberry Pi mounting:
    • 1 40-pin extra-height Pi connector
    • 4 M2.5 bolts (8mm, metal) ,4 M2.5 nuts
    • 4 M2.5 nylon hex spacers
  • Pi 5 external power button:
    • 1 tact switch, 6mm
    • 2 30cm F/F Dupont ('rainbow ribbon') wires
    • 2 male pin headers 1*2
  • Spacewar Game Controller set:
    • 2 Controller PCBs​
    • DE-9 Male connector, with case and nuts/bolts
    • 2 meters of 5-strand cable, 5x0,14mm2, diameter 3.9mm
    • 10 tact switches, 6mm
    • 12 diodes, 1N4148
    • 4 zip ties (2.8mm width)
​There are some spare parts in the kit.
Additional Parts List for the PiDP-1 Rack version

Additional parts for Rack version:

Main Rack Panels

Additional Panels

PiDP-1 Rack - Additional Parts:

  • (to the left:)
    18 additional PCB panels in total
  • Parts for IO Panel:
    • 49 flat top LEDS
    • 74HC04 hex inverter IC
    • udn2981 or equivalent driver IC
    • 1 male pin headers, 2*13 pins, straight (Mounted on main PiDP-1 PCB)
    • 1 male pin headers, 2*13 pins, angled (Mounted on IO Panel PCB)
    • 30cm ribbon cable 2*13 pins
    • 1 4148N diode
  • Parts for Speaker Panel:
    • 8x M2.5 bolt/hex spacer/nut set to mount speaker back panel
    • 4x M3 bolt/nut set to mount speakers in speaker panel
    • Speaker foam mat
    • 1x audio amplifier module
    • 1x knob for audio amplifier, with mounting nut
    • 3 male pin headers 1*2 for amplifier
    • 1 female pin headers 1*2 (for main PCB-5V power to amp)
    • 2x speaker
    • 20cm red&black speaker wires to connect speakers
    • 1x 3.5mm audio jack with 30cm wire to connect amplifier
    • 1x USB-2.3mm audio USB dongle
    • 2 30cm F/F Dupont ('rainbow ribbon') wires (to be cut in half!)
      4 10cm F/F Dupont ('rainbow ribbon') wires (amp to speaker frame)
    • 2 pin headers 1*2 pins (for speaker frame)
    • 2 30cm M/F Dupont ('rainbow ribbon') wires (amplifier 5V power cable)
  • Parts for Paper Tape Panel:
    • 2 USB Type A panel mounts with USB cable (50cm cable length)
      (come with 2 mount screws each)
  • Parts for Aluminum Frame:
    • 2 alumimum profiles, length cm (sides of frame)
    • 2 aluminum profiles, length cm (top/bottom of frame)
    • 4 aluminum T profiles (spacers between panels)
    • 4 metal frame corner fasteners (sets of 2 metal plates with 2 screws)
    • 2 wall mount clips (sets of clip with screw)
    • (4 frame spacer sets of spacer and bolt)
​There are some spare parts in the kit.

Prepare your Pi

Introduction

The pidp1 software runs fine on a 'naked' Raspberry Pi, without the PiDP-1 board. Set up your Pi before you start soldering. To play with the PDP-1 before you build the PiDP-1 hardware, we have provided an on-screen virtual front panel. So to configure your Pi for now, use pdp1control panel virtual. Enable the hardware panel again with pdp1control panel pidp before testing the hardware! The tell-tale sign: if you see a virtual front panel on your display, the PiDP-1 hardware front panel is not enabled yet. Lest you forget...

Any Pi from the Pi Zero 2 on up can be used. A Pi 4 is the minimum when you want to view the Type30 display on the Pi itself, and not through the Web interface. A Pi 5 is recommended if you also want to use the Pi as a normal Pi concurrently with the PDP-1.

The following is just FYI: you can get a terminal attached to the PiDP-1 in different ways. For now, testing using option 1 is good enough:

  1. 1. Use a HDMI monitor and a USB keyboard, and run everything on the Pi; for now, enable this mode through pdp1control set gui
  2. 2. You can also use your laptop to access the PiDP-1 over wifi, using its built-in web server: this lets you run the PiDP-1 headless.
    Just place it on a bookshelf or hang it on a wall.
  3. 3. The PiDP also has a serial port, to connect real serial terminals, or Teletypes.

Example image

It is mentioned further down in the building instructions, but for people who buy the PiDP-1 as assembled & tested: the Pi sits close to the PiDP-1 circuit board. Avoid any risk of short circuits: protect the metal USB connectors on the Pi with a strip cut from plastic or thin cardboard.

Actual Install Steps

The PiDP-1 requires the 64-bit version of the Raspberry Pi OS. First, set up your Pi like any normal Pi: create a SD card, boot the Pi with it, set up your internet connection. Then install the pidp1 software:

cd /opt
sudo git clone https://github.com/obsolescence/pidp1
/opt/pidp1/install/install.sh

Answer 'y' to all questions of the install script. You can rerun the install script later to change the setup.

First look around the PDP-1

Reboot. The PDP-1 will start, but you don't have a front panel attached, so you don't see Blinkenlights. Press F11 to switch the PDP-1 display to/from full-screen. Open a terminal window. You could set things up so that you don't see any Linux. But for now, the setup is such that you can use the Raspberry Pi concurrently as a normal Pi and a PDP-1.

As you currently are still Blinkenless, use the on-screen virtual front panel. Stop the simulator with pidp1control stop, then pdp1control panel virtual and pidp1control start again. See the PiDP-1 manual for more usage information!

The manual:

It will tell you much more about how to operate the PiDP-1. It (link) is updated regularly, it is still a work in progress. Revisit now and then so as not to miss out.

Also, do not miss the subpages on gaming & demos, assembly programming, and Lisp.


The PiDP-1 Google Group:

You're very welcome to join the PiDP-1 Google Group without the actual PiDP-1 hardware by the way - our goal is to revive the PDP-1, not necessarily to sell kits.

Choice of user interface:

To the right: we made three different user interfaces. The GUI is meant for use on a stand-alone PiDP-1, the Web interface is ideal if you place the PiDP-1 somewhere on a bookshelf, it can remain headless and just provide everything over wifi. The Apps interface is more geared to special use cases, such as museum exhibits. It is very flexible, but requires some Linux foo.
Choose your preferred interface:

GUI interface, on the Pi: pdp1control set gui Web interface, remote: pdp1control set web Apps interface, custom setups: pdp1control set apps It's all a matter of preference. Start with the GUI

Time to solder. Unless you got the PiDP-1 assembled & tested of course, then you're done after inserting the Pi.

An overview of the steps to come: Small jobs: You'll build the case (✔), a narrow 8-switch PCB (✔), and the game controllers (✔).
The main job is building the front panel unit (✔), which ends up as a sandwich of three panels: actual PCB, Ottopanel to help fix parts in place, then the front panel.
As follows:
PiDP-1 construction

1. Build the PiDP-1 case

Console Version

As it turned out, seeing this is much quicker than describing it in words. So please view the case assembly video below first. We apologise for not being pro Youtubers, but the content speaks for itself.


Extra tips in addition to the video
  • all panels are clearly marked with text to identify them and to show which way should point to the front. Make sure this text always is on the INSIDE of the case
  • check that the panels sit tightly against each other when soldering them together. If not: reheat & reseat the first solder point you made to join them
  • there are guidelines on the inside of some of the panels to check you indeed solder them together straight
    (although the angled front already ensures that to a large extent)
  • the video shows how to hold the case with one hand, soldering up with the other. It's quite easy if you follow the video
  • you can't really mistake one case panel for another. With the exception of the bottom Ottopanel (Ref.#9, the part of the front panel that will hold the 8 large control switches later on). This part has Ref.#9, not Ref.#13 (check the reference numbers in the parts list above, or on the part itself). Although, if you make this mistake, not too much of a problem really.
  • note that you're making most of the case here. Later on, you will add the top Ottopanel with the main PCB already attached to it. And right at the end, you can click in the top and bottom back panels.



Some pictures to add high-res clarity to the video. Click to zoom, click again to zoom further.
PiDP-1 construction

Inside view of th