The PDP-8 Instruction Set

This document serves as a technical reference guide for the instruction set of the PDP-8 computer. It provides a comprehensive list of assembly language mnemonics, their corresponding numerical codes, functional descriptions, and execution times (in microseconds).

The instructions are categorized into several functional groups, including:

• Basic Instructions: Fundamental operations such as logical AND, addition, jumping, and I/O transfers.
• Operate Microinstructions: Specialized commands divided into Group 1 (shifting, rotating, and clearing) and Group 2 (skipping and halting) operations.
• Combined Operate Microinstructions: A set of advanced, multi-action commands.
• TTY (Teletype) & Printer/Punch Instructions: Controls for input/output devices including keyboard, reader, printer, and punch components.
• Random Access Disc File (Type DF32): Specific commands for managing disk memory, including loading addresses, reading, and writing operations.