PDP-7 Program Library

This document details a collection of programs for the PDP-7 computer, designed to facilitate various operations using DECtape and the computer's toggle switches. The primary goal of these programs is to detect errors within the DECtape Control system.

The document outlines 19 distinct subroutines, each with specific functions and usage instructions. These functions include:

• Data Manipulation: Writing, reading, and comparing data blocks on tape (e.g., TSTMM, MMWRT, MMREAD).
• Tape Preparation: Writing mark tracks and virgin tape patterns in both forward and reverse directions (e.g., WRMKTR, WRVIRG, RWMKTR, WRNVT).
• Data Integrity Checks: Performing sum checks on data and block marks in forward and reverse directions (e.g., SUMF, SUMR).
• Pattern Generation: Creating specific data patterns, including desired patterns, arithmetic progressions, and random numbers, for writing to tape (e.g., MMGEN, MMGENA, MMGENR).
• System Diagnostics: Comprehensive tape exercisers that continuously write, sum check, and detect errors, including a special exerciser for user-defined patterns (e.g., EXER, SPEXER).
• Tape Movement & Control: Programs for moving tape for fixed durations, adjusting stop delays, and reading block numbers (e.g., ROCKER, BLROCK, STAP, RBMN).

Each subroutine description provides detailed instructions on how to set the Accumulator Switches (ACS) for parameters like unit number, starting block, and number of words or blocks. The document also describes a standardized error message format, lists various error codes (e.g., format error, sum check error, timing error), and explains how to interpret error output. Equipment requirements include a Paper Tape Reader, Teleprinter, and DECtapes.