DTSER2 Executive System DEC-Tape Service with Stacking L. Hantmann 8-2-65 Multiple Directories Version

This document is an assembly language listing for the DTSER2 Executive System, designed to provide DEC-Tape service with stacking capabilities and support for multiple directories. Developed by L. Hantmann in August 1965, the code outlines various routines for managing tape operations and directory functions. Key components include subroutines for directory search (UDIRSH, ULOOK), entering or updating directory entries (UENTER), and utilities for clearing and initializing tapes (UTPCLR). It also specifies constants for tape unit characteristics, buffer management, data control, and error handling. The document details procedures for reading and writing data blocks, handling buffer addresses, managing directory entries, controlling tape movement, and processing interrupts. The listing concludes with a symbol table defining internal and external labels and their memory addresses.