M9301 Bootstrap/Terminator Maintenance and Operator's Manual

This document is the M9301 Bootstrap/Terminator module maintenance and operator's manual for Digital Equipment Corporation (DEC) PDP-11 computers.

The manual describes the M9301 module, which integrates Unibus termination resistors and 512 words of Read-Only Memory (ROM). This ROM contains essential bootstrap programs, diagnostic routines, and a console emulator.

Key aspects covered include:

• General Description and Features: The M9301's role in combining Unibus termination with bootstrap capabilities, its physical specifications as a double-height Flip-Chip module, and its compatibility with various PDP-11 systems (with some versions tailored for specific models like the PDP-11/70).
• Bootstrap Initiation: How boot programs can be initiated through power-ups, direct program jumps, console commands, or external switch closures.
• Hardware Description: Detailed explanations of the module's electrical specifications, power-up sequence, power-up booting logic, external boot circuits, address detection, and ROM address generation.
• Console Emulator: A significant portion of the manual describes the console emulator firmware, its functions (Load Address, Examine, Deposit, Start), and procedures for booting from various peripheral devices (e.g., paper tape, disk, magnetic tape, DECnet). It also includes troubleshooting for console emulator errors.
• Extended Addressing: Information on virtual and physical addresses and memory mapping, particularly for PDP-11 systems with memory management enabled or extended memory beyond 28K.
• Version-Specific Details: The document dedicates separate chapters to various M9301 versions (M9301-0, -YA, -YB, -YC, -YD, -YE, -YF, -YH, -YJ), detailing their unique memory maps, microswitch settings, specific bootstrap programs, and diagnostic test procedures (including CPU, memory, and cache diagnostics).

The manual is intended for users with a general knowledge of digital circuitry and basic understanding of PDP-11 computers.