PDP-6 Multiprogramming System Manual

This manual provides a comprehensive description of the PDP-6 Multiprogramming Monitor version 1, a time-sharing system designed to enable multiple users to simultaneously access system facilities and programs via Teletype consoles. A core feature of the system is its ability to protect user programs within core memory and to prevent interference between different users' I/O operations. DECtape serves as the primary storage medium for user files.

The document covers the following key areas:

• System Fundamentals: It introduces the basic features of the time-sharing system, including file generation, on-line debugging, common user service programs (CUSPs), unattended batch processing, special console services, and real-time processing capabilities.
• Hardware and Architecture: It details the minimum and optional hardware requirements for the system and discusses the multiprogramming system's block diagram, including user consoles, executive functions, input/output structures, core storage allocation, and file management.
• Console Operation: A significant portion describes the time-sharing console operation, covering various console states and a wide range of commands for initializing, starting, managing, debugging, and terminating jobs.
• User Programming: It explains programming aspects for users, such as system parameters, the pushdown list, input/output instructions, buffer management (ring buffers), job and device initialization, data transmission, status checking, and I/O synchronization. Detailed sections are dedicated to specific devices like Teletypes, paper tape equipment, line printers, card readers, DECtape, and magnetic tape.
• Error Handling: The manual outlines error diagnostics, including monitor-detected errors, illegal memory references, illegal instructions, and output to incorrect devices, along with recovery procedures.
• Standard CUSP Library: It provides an overview of the Common User Service Programs available, such as FORTRAN, MACRO, EDITOR, LOADER, DESK, DDT, JOBDAT, FORLIB, FUDGE, and RIMDTA, detailing their functionalities and operating instructions.
• Appendices: These sections delve into the executive components, the monitor's scheduling algorithm, symbol definitions used within the system, and detailed monitor operating instructions.

Overall, the manual serves as a complete guide for understanding, operating, and programming for the PDP-6 Multiprogrammed Time-Sharing System, emphasizing its capabilities for efficient multi-user access and resource management.