PiDP-1
PiDP-10 article in The Guardian<br>-- CuriousMarc's PiDP-10 YouTube episode
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Special topics:
Games & Graphics demos
Assembly Programming
Lisp Programming
Music: Harmony compiler
Youtube (click): PiDP-1 Console up close
PDP-1 Youtube: Harmony Music Compiler
Youtube: Using front panel & DDT
As kit or assembled/tested:
Buy The One
Build & Use the PiDP-1:<br>Building Instructions
2025 PiDP-1 Manual
1963 PDP-1 Manual
PiDP1 development blog:<br>Hackaday blog
The user group:<br>PiDP-1 Google Group
The PDP-1 was the first computer made by DEC - Digital Equipment Corporation, based on MIT's TX-0 and TX-2 experimental computers.<br>Its history is told very well on Wikipedia. A team at the CHM has restored one PDP-1 to working order; and Angelo Papenhoff has written exact simulators in both Verilog and C - including the Type 30 display. Our replica is based on this simulator.
Three years ago, we started work on a replica, to complete the PiDP series (-8, -10, -11). Little did we know that this adorable dinosaur would become our favourite of the whole range. The PDP-1 is a truly fun machine to work and play with - and so, this text turned out a bit less formal than the other machines' pages.
PiDP-1 Rack version
PiDP-1 Console version
The PDP-1 was a first in many respects. But it is also simple enough to be quickly understandable to any 21st century computer user. It remains the original Hacker's machine. - the word comes from the hacker community forming around the PDP-1 at MIT; their demo programs are still attractive eye candy thanks to the Type 30 display. Which was a converted radar display.
Driving the electron beam over its phosphor, you can get very pretty graphics effects from only a little bit of simple programming. But serious programs were also written, despite the minimal resources of the machine it spawned the first-ever text editors, a sensational Lisp, and FORTRAN. Even the first interactive multi-user system software. Much of this has been preserved and brought to run again.
Exactly because of its simplicity, this is the machine we'd really want to learn assembly language on. Before you laugh, let us give an overview of the machine from three different perspectives. Forgive us for such frivolity with a historical machine.
Is it a stretch to call a $100,000 computer from 1959 a games console? No. It is where the computer video game was invented: Spacewar! And it is where games controllers were first introduced. Games are still being written for the machine - hackers still exist :-)
The PDP-1 was tiny enough so that it could not do too many things. Elegant, mean and lean graphics demos were thus a natural application for it. And that's not a trivial thing; a lot of graphics algorithms were invented here. And the notion of interactive graphics.
Many ideas were born on the One: text editor, interactive debugger, the REPL idea now famous from Python. And timesharing: it's the first-ever multi-user system. And a PDP-1 was Arpanet's real-time monitor, pushing the first-ever online software updates, to routers in the field.
Of all the pre-home computer systems we played with over the years, this is the most fun. Look at it as the first games console, then as the first democoder platform, and then read about the Serious Work that was done on this historical computer. It deserves to live on in the 21st century. Just a few dozen lines of surprisingly simple assembly give pretty cool graphics on the radar tube, and we want to show you!
The One comes in many forms
DEC had trouble making up its mind on the appearance of the PDP-1.
It made a few table-top 'console panels', but then decided to mount the panel on the side of the rack. And they frequently alternated between white and blue front panels.
Who, then, are we to make such important choices for the replica? We chickened out: the replicas come with interchangeable white and blue front panels.
Also, we decided to build both the racked and a console variants, thus leaving the hardest decision to you. There is a way out, though: if you opt for the rack, it comes with a spare console case as well. You can transplant the PCBs at any time, and continue the heritage of indecision. If DEC itself could not make up its mind, it is probably important to remain undecided... :-)
Historical significance
The PDP-1, introduced by Digital Equipment Corporation in 1960, marked a turning point in computing. It was the first commercial computer designed for interactive use rather than batch processing, enabling real-time programming, debugging, and display output. The PDP-1 was the platform for several historic software “firsts”: Spacewar! (1962), one of the earliest digital video games; early text editors; interactive debuggers; and pioneering time-sharing experiments at MIT.
Its low cost (only $120,000 in 1960) and accessibility brought computing out of the exclusive realm of mainframes and into research labs and universities. Hacker culture...