U/W Focal

This document serves as the user manual for U/W FOCAL, an expanded version of the PS/8 FOCAL programming language designed for use with OS/8 operating systems on DEC computers. Developed by Jim van Zee at the University of Washington (August 1978), U/W FOCAL offers significant enhancements to the original language, including 13 new commands, 15 additional function entries, 10-digit precision, double subscripting, variable file names, and improved performance for both laboratory applications and numerical problems.

Key aspects of the manual include:

• Language Features: Detailed explanations of arithmetic operators, special characters, input/output commands, and program control flow.
• Advanced Capabilities: Instructions on using double subscripting for matrix operations, "FOCAL Statement Functions" for creating custom code routines, and techniques for merging programs.
• System Integration: Extensive technical information for advanced users on adding new functions, managing hardware interrupts, and creating custom device handlers.
• Appendices: Comprehensive reference material covering ASCII character codes, a full list of error codes, and specific patches for hardware limitations, including a "date fix" to allow the system to display correct years beyond 1977.