The Omnibus Interface

This document serves as an introduction to the OMNIBUS interface system used in the PDP-8/E computer. It explains that the OMNIBUS is a hardware interconnect system consisting of an etched backplane board with standardized connector slots, which allows modules to be plugged into any position, eliminating complex point-to-point wiring.

Key details include:

• System Design: The OMNIBUS supports 20 modules per assembly and can be expanded to accommodate additional hardware using expansion units.
• Functionality: It simplifies the design of custom interface modules by providing a standard set of signals, including data, address, and control lines, to all slots.
• Configuration: The text outlines standard PDP-8/E configurations and provides guidance for expanding system capabilities through the addition of memory units, I/O interfaces, and peripheral control modules.
• Technical Specifications: The document provides basic logic level specifications and directs the reader toward specific sections for designing custom interfaces, understanding data transfer techniques, and selecting the appropriate hardware for various system needs.