PDP-11/40, -11/35 (21 Inch Chassis) System Manual

This document is the "PDP-11/40, -11/35 (21 inch chassis) system manual," published by Digital Equipment Corporation (DEC), with its fourth printing in January 1975. It serves as a comprehensive guide for users, operators, and maintenance personnel, assuming a basic understanding of digital computer theory.

The manual covers several key aspects of the PDP-11/40 and -11/35 systems:

1. Introduction: Provides an overview of the system's basic components, including the KD11-A Processor (a 16-bit, microprogrammed CPU with 18-bit Unibus addressing and vectored interrupts), the high-speed Unibus for all system communication, core memory (e.g., MF11-L), the KY11-D Programmer's Console, and standard I/O devices like the LA30 DECwriter and Teletype. It also outlines various internal processor options and references other detailed documentation.
2. Installation: Details the necessary site preparation (physical dimensions, environmental requirements, electrical needs), unpacking procedures, and steps for connecting AC power, Unibus, and intercabinet wiring.
3. System Operation: Explains how to interact with the system via the Programmer's Console for basic functions (starting, stopping, loading, examining programs), covers manual and automatic program loading (bootstrap, absolute, and maintenance loaders), and introduces basic programming concepts.
4. Processor Instructions and Options: Describes the PDP-11 instruction set, including single and double operand instructions, and provides specifications for processor options that enhance capabilities, such as the Extended Instruction Set (EIS) for arithmetic operations, Floating Instruction Set (FIS) for floating-point calculations, Memory Management (KT11-D) for expanded addressing, Stack Limit Register (KJ11-A), Line Time Clock (KW11-L), and Maintenance Console (KM11-A).
5. System Peripherals and Options: Lists a wide range of compatible peripherals, including various input/output devices (paper tape, line printers, card readers), magnetic tape drives, display systems, disk storage, bus extensions, communication interfaces, and data acquisition and control systems.
6. Equipment Mounting and Power: Details the physical mounting of system components within the BA11-FC Mounting Box and the overall system cabinet, and thoroughly describes the power system (861 Power Controller, H742 Power Supply, various regulators), including its interconnection and DC power distribution for different system versions.
7. General Maintenance: Outlines overall maintenance techniques, including preventive maintenance (physical checks, electrical adjustments), lists necessary maintenance equipment, and provides guidance on utilizing diagnostic programs for detecting and isolating hardware faults, with an emphasis on module replacement.

The manual frequently refers to other specific DEC handbooks and engineering drawings for more in-depth technical discussions on hardware, software, and interfacing.