PDP-11/84 System Maintenance Guide

This document is the PDP-11/84 System Maintenance Guide, published by Digital Equipment Corporation in November 1986.

It serves as a comprehensive resource for maintaining the PDP-11/84 computer system, covering:

• General System Specifications: Details the environmental, mechanical, and electrical characteristics of both cabinet and box system configurations, and lists related documentation.
• Diagnostic and Troubleshooting Aids: Provides methods for diagnosing system issues, including interpreting console error messages, utilizing ROM-resident startup diagnostics, and employing various commands within the J11 Micro ODT and dialog modes (e.g., HELP, BOOT, LIST, SETUP, MAP, TEST). It also describes the use of LEDs, switch packs, and jumpers on key modules (MDM, CPU, Memory) for fault isolation.
• Removal and Replacement Procedures: Offers step-by-step instructions for safely removing and replacing Field Replaceable Units (FRUs) such as CPU modules, power supplies, blowers, fans, front panels, circuit breakers, power controllers, SLU interface assemblies, CPU backplanes, and Battery Backup Units (BBUs).
• System Register Descriptions: Catalogs and explains the various system registers, including page address registers, page descriptor registers, memory management registers, cache registers, error registers, processor status word, interrupt request registers, UNIBUS mapping registers, and diagnostic controller registers.
• Option Installation Procedures: Guides users through the installation of expansion power supplies, expansion backplanes, Small Peripheral Controller (SPC) modules, and Battery Backup Units (BBUs).
• Appendices: Includes detailed backplane pin assignments and a worksheet for recording CPU setup parameters.