FRAP and DECAL

This document provides an introduction to two programming systems for the Programmed Data Processor (PDP), specifically for the PDP-1.

• FRAP (Symbolic Assembly Program): Allows programmers to write code using mnemonic instructions, octal numbers, and symbolic addresses. It includes a definition of basic terminology, symbolic program format, and a suite of floating-point arithmetic subroutines.
• DECAL (Compiler, Assembler, and Linking Loader): An integrated system that combines the one-to-one translation of an assembler with the one-to-many translation of a compiler. It supports problem-oriented language statements and facilitates the management of large programs by allowing separate compilation of program segments.

The document also covers miscellaneous routines such as the Typewriter Interrogator Program (TIP), which allows for interactive examiniation and modification of registers and program data via the typewriter.