KD11K Processor (PDP-11/60) Technical Description Manual Section 6 Maintenance Features

This document, Section 6 of the KD11K Processor (PDP-11/60) Technical Description Manual, details the maintenance features and procedures for the PDP-11/60 system.

It covers:

• Troubleshooting Aids: Describes built-in software and hardware features including extensive parity checking and error logging in dedicated status registers (e.g., Log Jam, Log Service, Processor Status Word, Memory Management Status Registers), and a Microaddress Match and Microbreak Register for advanced debugging.
• Diagnostic Tools: Explains the use of the Diagnostic Control Store (DCS) Module for microdiagnostics to isolate processor internal faults, and Macrodiagnostics (XXDP) for broader system and peripheral testing. It includes procedures for starting, operating, and interpreting the results of these diagnostics, along with the concept of a "SCOPE loop" for detailed signal observation and a "FAULT DIRECTORY" for error code interpretation and module replacement.
• Maintenance Procedures: Provides guidance for cold start troubleshooting (checking power, cabling, console functions), specific "toggle-in" routines for manual booting and CPU/console checks, and detailed instructions for hardware removal and replacement, particularly for modules and Integrated Circuits (ICs), including recommended tools and cautions.
• Configuration Management: Outlines the use of Module Utilization List (MUL) and Engineering Change Order (ECO) status stickers for tracking equipment configuration and revisions.