Alphanumeric Message Typeout

This document provides the technical documentation for a PDP-8 assembly language subroutine designed to output alphanumeric messages to an ASR-33 Teletype.

Key details include:

• Functionality: The program processes messages packed as two 6-bit characters per computer word. It handles character extraction, conversion, and transmission to the terminal.
• Special Handling: It includes logic to map specific internal codes to ASCII characters, including designated overrides for line-feed and carriage-return functionality.
• Requirements: The subroutine requires 48 (decimal) storage locations and utilizes autoindex register 10.
• Implementation: The document provides the complete assembly source code, a detailed explanation of the method used to unpack and transmit characters, and tables defining the supported (legal) and unsupported (illegal) character codes.