VT240

Introduction

The VT240 added monochrome ReGIS vector graphics support to the base model, while the VT241 did the same in color. The 200 series replaced the successful VT100 series, providing more functionality in a much smaller unit with a much smaller and lighter keyboard. Among its major upgrades was a number of international character sets, as well as the ability to define new character sets. The VT200s were the last DEC terminals to provide a 20mA current loop serial interface, an older standard originally developed for the telegraph system but became popular on computers due to the early use of Teletype Model 33's as terminals. A standard 25-pin D-connector was also provided for RS-232. Only one of the two ports could be in use at a given time. Later DEC terminals, VT3XX series, would replace both of these with their proprietary Modified Modular Jack (MMJ) connectors.

The three main components of the VT240 series terminals are the monitor, the system box, and the keyboard. The VT240 and VT241 terminals use the same system box and keyboard; the only difference between the terminals is the monitor. The VT240 has a monochrome monitor, while the VT241 has a color monitor.

Monitor
The monitor consists of a monochrome or color cathode-ray tube (CRT) and a monitor board. A single cable connects the monitor to the system box.

System Box
The system box is the electronic center of the terminal. The main parts of the system box are a power supply, a controller board that contains the central processing unit and electrical connectors.

Keyboard
The low-profile keyboard has four groups of keys and four visual indicators. The main keypad operates like a typewriter keyboard. A single coiled cable connects the keyboard to the terminal. There are 15 basic keyboards available with the VT240. Each keyboard is for a different language.

Operating Modes
The VT240 has five major operating modes. You can select these modes in setup. The default operating mode is VT200 mode, 7-bit controls. A default setting is a factory setting the terminal uses until you change that setting.

• VT200 mode, 7-bit controls
• VT200 mode, 8-bit controls
• VT100 mode
• VT52 mode
• Tektronix 4010/4014 mode