PDP-8/e Replicated — Clocks And Logic

This is, at long last, part 3 of the overview of my PDP-8/e replica project and offers some details of the low-level implementation. I have mentioned that I build my PDP-8/e replica from the original schematics. The great thing about the PDP-8/e is that it is still built in discrete logic rather than around a microprocessor, meaning that schematics of the actual CPU logic are available instead of just programmer’s documentation. [Read More]

PDP-8/e Replicated — Overview

This is an overview of the hardware and internals of the PDP-8/e replica I’m building. The front panel board If you know the original or remember the picture from the first post it is clear that this is a functional replica not aiming to be as pretty as those of the other projects I mentioned. I have reordered the switches into two rows to make the board more compact (which also means cheaper) without sacrificing usability. [Read More]

PDP-8/e Replicated — Introduction

I am creating a replica of the DEC PDP-8/e architecture in an FPGA from schematics of the original hardware. So how did I end up with a project like this? The story begins with me wanting to have a computer with one of those front panels that have many, many lights where you can really see, in real time, what the computer is doing while it is executing code. Not because I am nostalgic for a prior experience with any of those — I was born a bit too late for that and my first computer as a kid was a Commodore 64. [Read More]