Dial-MS PxDxSrc Program Description

This document describes the DIAL-MS PXDXSRC program, an editor, filing system, and assembler for the PDP-12 computer. The program's core components are derived from Mary Allen Wilkes's LAP6 (for editor and filing) and PDP-8 assembly programs like PAL-D (for assembly). PXDXSRC comprises two main parts: Display Index and Print Index. Both parts scan directory indexes and display or print filenames. The Display Index offers interactive control via keyboard commands, allowing users to adjust the display's line count ('1', '2', 'Q', 'W'), re-read the index ('R'), delete the last displayed line ('rubout'), or write the current index to tape (':'). The program occupies memory blocks 361 and 362 (locations 4000-4777) and uses a portion of the PRINTMS output routine (block 364) for Teletype operations. The document includes an overview, environmental details, flowcharts illustrating program logic, and a full assembly listing.