The OMNIBUS Interface

This document, Chapter 9 of the PDP-8/E handbook, details the OMNIBUS interface. It provides comprehensive technical information for designers wanting to build special interface modules. Key topics include:

• Bus Structure & Specifications: Descriptions of the 96-signal etched board bus, slot configuration, and logic voltage levels.
• Data Transfer Methods: Explanations of Programmed I/O, the Interrupt Facility, and the high-efficiency Data Break Transfer system.
• Design & Construction: Detailed guidelines on device selection circuits, operations decoders, signal timing (with timing diagrams), and loading rules.
• Interface Examples: Specific logic implementations for Programmed I/O and Data Break interfaces.
• Hardware Accessories: Overview of available DEC modules and components (like bus drivers, receivers, and connectors) to facilitate design.

The document includes extensive tables of OMNIBUS signals and their functions, as well as electrical and physical design check lists.