The PDP-8: How a 12-Bit Minicomputer Made Computing Affordable

From Front Panel to Program: Thinking Like a PDP-8

The PDP-8: How a 12-Bit Minicomputer Made Computing Affordable

The PDP-8, introduced in 1965 for around $18,000, was a 12-bit minicomputer that brought computing to labs and factories. Its simple accumulator-based architecture, with a tiny instruction set and a one-bit link register, made it easy to understand. The PDP-8 family evolved from discrete transistors to integrated circuits while keeping the same programming model, proving that a stable architecture can outlive its implementation.

The PDP-8 is a 12-bit computer that has a tiny instruction set, a single main accumulator, a peculiar memory-addressing scheme, a one-bit link register, instructions that perform several jobs at once, and even a handful of registers that aren't actually registers at all.
  1. Animats

    There's also a working PDP-10 console replica you can buy.[1]

    There was a really nice IBM 1401 data center simulator written in Unreal Engine at [1]. You could mount tapes, punch cards, push buttons, and actually operate the machine. But the site is gone. There's some archived material.[2] But even his Youtube videos are now "Private". Here's someone else running his simulator.[3]

    I hope the simulator hasn't been lost.

    [1] https://obsolescence.dev/pdp10.html

    [2] https://web.archive.org/web/20250605101441/https://rolffson....

    [3] https://www.youtube.com/watch?v=ZE4jiV99ECU

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2026-09-11