VT420

The VT420 was an ANSI standard computer terminal introduced in 1990 by Digital Equipment Corporation (DEC). The 420 was the only model in the 400 series, replacing the VT320. There were no color or graphics-capable 400 series terminals; the VT340 remained in production for those requiring ReGIS and Sixel graphics and color support. The entire lineup of VT300s and VT420 was eventually replaced by the relatively unknown VT500 series starting in 1993.

Description

The VT420 consisted largely of a combination of the VT320 with the virtual terminal support of the VT330 and VT340. Those two models had included a system known as TD/SMP which allowed two sessions to be multiplexed over a single serial connection to a compatible terminal server. Alternately the two sessions could be supported by separate serial connections on those models with multiple MMJ ports. Using either method, the VT330/340/420 could either show the two sessions behind each other, using a key sequence to flip back and forth, or split the screen horizontally to display the sessions one above the other, or vertically side-by-side.