Focal-8

This document is a source code listing for FOCAL-8, a version of the FOCAL programming language designed for the Digital Equipment Corporation PDP-8/E computer. The document includes:

• Program Metadata: The listing, generated on January 18, 1974, by user "MITCHELL,M," is labeled as LPTSPL version 4(137).
• System Identification: It identifies the software as FOCAL-8, an on-line formula calculator and compiler for algebraic languages, copyrighted by Digital Equipment Corporation in 1971.
• Technical Details: The document provides assembly instructions, pseudo-floating point instructions, memory map information, input/output routines, interrupt processing, and a detailed cross-reference table of symbols and labels used in the source code.
• Functionality: The code contains routines for input processing, line number formation, command handling, floating-point arithmetic (including exponential and trigonometric functions), and various hardware-specific routines for the PDP-8/E.