Digital LA 120

This document is a comprehensive user guide for the Digital LA 120 DECwriter III terminal, designed to assist users in its operation and integration with computer systems. It highlights the terminal's typewriter-like functionality and its compatibility with EIA and ANSI standards.

The guide is structured into several key sections:

• Operator Information: Details the terminal's console features, including lights, a numeric display, and various keys. It provides procedures for setting up forms (e.g., margins, tabs, lines per inch, form length), customizing operator comfort features (e.g., auto repeat, last character view, bell volume, key click), and configuring communication settings (e.g., baud rate, answerback, buffer control, character sets, auto disconnect, local echo, auto new line, modem protocols, parity/data bits, XON/XOFF, alternate keypad mode, and break action). It also covers storing and recalling settings, checking status, performing self-tests, and instructions for ribbon and paper loading.
• Installation, Interface, and Specifications: Outlines step-by-step procedures for unpacking, inspecting, and configuring the LA 120, including setting the voltage selector switch. It provides in-depth information on the EIA interface, cables, impedance, and electrical characteristics. Detailed specifications for the printer, keyboard, communication capabilities, and physical dimensions are also included.
• Programmer Information: Explains how to control various LA 120 features using ANSI-standard escape sequences. This includes managing printer character sets, active position, horizontal and vertical pitch, margins, tabs, form length, product identification, line feed newline mode, and alternate keypad mode, along with a reference for control characters and the APL character set.
• Communications: Covers full-duplex (FDX) and half-duplex (HDX) communication modes, specifying connection requirements, break signals, disconnect conditions, restraint versus speed control modes, initial direction determination, reverse channel, modem delays, and turnaround characters. It also describes modem setup features and the effects of paper out.
• Options: Describes optional enhancements, such as the 20 mA LA12X-AL current loop option for direct computer communication without a modem and the LA12X-DL expanded buffer for increased character storage capacity.
• Supplies and Accessories: Lists recommended supplies (e.g., various paper types, multipart forms, ribbons) and accessories (e.g., casters, paper basket, wire shelf, copy holder, dust cover) to enhance terminal reliability and ease of use, along with ordering information and a list of related manuals.

The document serves as a comprehensive resource for anyone involved with the operation, installation, or programming of the LA 120 DECwriter III.