AA-H654A-TM BasicPlus2 Lang Oct79

This is the TOPS-20 BASIC-PLUS-2 Language Manual (AA-H654A-TM), published by Digital Equipment Corporation in October 1979.

It serves as a comprehensive reference guide to the BASIC-PLUS-2 programming language as implemented on the TOPS-20 Operating System. The manual is not intended as a primer or user's guide for beginners.

Key topics covered include:

• The fundamental elements of BASIC programs and language.
• Instructions for using BASIC-PLUS-2, including commands and immediate mode operations.
• Input and output operations to and from the terminal.
• Program control statements (e.g., loops, conditional transfers).
• Program segmentation using subprograms and chaining.
• A detailed description of built-in and user-defined functions (numeric, string, conversion, date/time, system, terminal-format file).
• Working with arrays and matrix operations.
• Various file types: terminal-format, virtual-array, and record files, including opening, closing, reading, writing, renaming, and deleting.
• Formatting output using the PRINT USING statement.

Appendices provide diagnostic messages, information on using the TOPS-20 operating system, a list of reserved BASIC words, and an ASCII code table, along with summaries of statements, functions, and operators.