Pdp-8/e and Pdp-8/m Small Computer Handbook

This document provides a comprehensive technical overview and operational guide for the Digital Equipment Corporation (DEC) PDP-8/E and PDP-8/M computers.

Summary

• System Architecture: The PDP-8/E is a 12-bit, general-purpose, fixed-word-length computer using a common "OMNIBUS" architecture. The PDP-8/M is a functionally identical, OEM-focused version. The system relies on a central processor, core memory, and various interface modules (registers, timing generators, etc.).
• Operations & Controls: The manual details the Programmer’s Console and its switches (Load Address, Examine, Deposit, etc.) used for manual data manipulation. It also outlines the usage of the ASR-33 Teletype for I/O operations, including paper tape formats (ASCII, RIM, and BIN).
• Loading Programs: The document explains the bootstrapping process: how to manually toggle in the RIM loader, which in turn allows for the loading of the BIN loader, and subsequently, how to use the Symbolic Editor and PAL III assembler to prepare, edit, and assemble programs.

• Instruction Set: Chapter 3 classifies instructions into three categories:

  • Memory Reference Instructions: (AND, TAD, ISZ, DCA, JMS) used for data manipulation and program flow.
  • Augmented Instructions: Operate within the CPU (e.g., OPERATE/OPR and IOT).
  • Housekeeping Instructions: (JMP) for program control.

• Advanced Features: The text covers topics such as Program Interrupts, the Extended Arithmetic Element (EAE) for advanced mathematical operations, and the search feature in the Symbolic Editor.