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VT100
The VT101 and VT102 were cost-reduced non-expandable follow-on products, with the VT102 including the AVO and serial printer port options of the VT100. The VT100 became a platform on which Digital constructed related products. The VT105 contained a simple graphics subsystem mostly-compatible with the earlier VT55. The VT125 added an implementation of the byte-efficient Remote Graphic Instruction Set (ReGIS.) The VT103 added a built-in LSI-11 processor while the VT278 added a built-in PDP-8 processor, allowing the terminal to run Digital's WPS-8 word processing software. The VT180 (codenamed "Robin") added a single-board microcomputer using a Zilog Z80 to run CP/M.
In 1983, the VT100 was replaced by the more-powerful VT200 series terminals such as the VT220.