VT05 Alphanumeric Display Terminal Reference Manual

This document serves as a reference manual for the VT05 Alphanumeric Display Terminal, detailing its purpose, functional components, and operational procedures.

The VT05 is a CRT display with an integrated keyboard, designed for use as a computer I/O device or a standalone closed-circuit television monitor. It enables users to compose, edit, and transmit messages, retrieve and update data, and perform on-line debugging. Capable of displaying 20 lines of 72 characters (1440 total), it is a raster-type display compatible with EIA standards, allowing alphanumeric text to be superimposed on video images. It offers advantages over traditional teletypewriters in terms of speed, quietness, compactness, and reliability.

Functionally, the VT05 consists of a keyboard, CRT display, transmit/receive logic, control logic, recirculating memory (9816 bits), and a character generator/ROM. The character generator converts ASCII codes into a 5x7 dot matrix for display, rendering all received lowercase characters as uppercase. The terminal supports both full and half ASCII character sets, operates asynchronously at selectable baud rates, and interfaces via EIA RS-232-C/RS-330 or a 20-mA current loop. High baud rates may require filler characters after certain control commands for proper processing.

Operational aspects covered include turn-on procedures for both local (off-line) and remote (on-line) modes, and explanations of full- and half-duplex communication. Keyboard functions include control keys for special operations like producing an audible "BELL" tone or initiating Direct Cursor Addressing (CAD), shift keys for character variations, and an ALT key for programming alternatives. Display controls encompass cursor movement (left, right, up, down, home, horizontal tab), and various text erase functions (erase-to-end-of-line, erase-to-end-of-screen, individual character deletion, character replacement). Automatic functions include screen scrolling, automatic cursor advancement, and an end-of-line warning tone. Direct Cursor Addressing facilitates precise cursor placement for efficient data updates. The manual also outlines basic preventive maintenance, such as cleaning and relocation guidelines, and advises contacting DEC Field Service for malfunctions.