ETOS

This document is the official System User's Guide for the Extended Timeshared Operating System (ETOS), Version 5B, designed for Digital Equipment Corporation's PDP-8/E, /F, /M, and /A computers. The guide provides a comprehensive overview of the system architecture, which enables multi-programming and time-sharing by providing virtual PDP-8 environments to users.

Key contents include:

• System Overview: Explanation of the ETOS architecture, virtual machines, and time-sharing mechanisms.
• SCALE (System Command and Login/Logout Executive): Detailed documentation on monitor commands, including how to log in, handle system errors, manage memory with the CORE command, and execute tasks.
• OS/8 Integration: A section dedicated to the operational differences and modifications required to run OS/8 under ETOS, including supported programs and file management.
• COS Integration: A section covering ETOS-specific adjustments for the COS operating system and the use of the SYSGET program for system generation.
• Assembler Programming: Guidelines for writing and converting assembler programs to run efficiently under ETOS.
• Appendices: Reference materials including lists of SCALE commands, error messages, and a glossary.