OS/78, Version 2, DECstation 78 Operating System

OS/78 is a comprehensive executive for the DECstation 78 computer system. It offers application software development tools and an efficient runtime environment. The system is managed by a Concise Command Language (CCL) that simplifies program development and execution. Programs can be accessed from diskettes via simple keyboard commands for loading, modification, or execution. OS/78 supports program chaining, allowing complex programs to be divided into smaller modules.

CCL provides access to three classes of functions: system, language, and utility. System functions include Batch Processing (using the SUBMIT instruction for executing command sequences from a file) and I/O Handlers that support various printers and serial line units, along with system configuration options via the SET command. Concurrent Processing allows user-written assembly language programs (symbionts) to run in parallel with OS/78, utilizing the upper 4K words of memory for tasks like communications or printing.

Language functions include OS/78 BASIC, an interactive compiler language with an editor, compiler, and runtime system. It supports multiple data formats, commercial decimal arithmetic, formatted printing, full upper/lower case, cursor control, and random-access record I/O. The system also includes a three-pass assembler (PAL) and OS/78 FORTRAN IV, which supports generalized array subscripting, 1- to 7-dimension arrays, and direct access I/O.

Utility functions encompass a HELP utility for displaying instructions, an EDIT utility for creating and modifying ASCII source files, a LOAD absolute loader for reading binary programs, ODT (Octal Debugging Technique) for controlled program execution and debugging, CREF for cross-referencing symbols in assembly language programs, MAP for constructing memory usage tables, DIRECT for listing file directories, and DUPLICATE and COPY commands for diskette and file transfer operations.

The document also outlines minimum hardware requirements (DECstation 78/40), optional hardware, prerequisite software (none), and optional software (MACREL/LINKER). It details support categories, update policies, and ordering information, including media types and licensing terms. Specific standard and upgrade options for DECstation 78 systems are listed, along with support categories A, B, and C, which define the level of service provided for software defects and updates.