Dynamically Redefined Character Set

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The Dynamically Redefined Character Set, or DRCS for short, was a feature of Digital Equipment Corporation's smart terminals starting with the VT200 series in 1983. DRCS added a RAM buffer where new glyphs could be uploaded from the host system using the Sixel data format.

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The Multinational Character Set is a character encoding created in 1983 by Digital Equipment Corporation (DEC) for use in the popular VT220 terminal. It was an 8-bit extension of ASCII that added accented characters, currency symbols, and other character glyphs missing from 7-bit ASCII. It is only one of the code pages implemented for the VT220 National Replacement Character Set (NRCS). MCS is registered as IBM code page/CCSID 1100 since 1992. Depending on associated sorting Oracle calls it WE8DEC, N8DEC, DK8DEC, S8DEC, or SF8DEC.

VT220 Computer terminal from Digital Equipment Corporation

The VT220 is a computer terminal introduced by Digital Equipment Corporation (DEC) in November 1983. 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. Like the VT100, the VT200 series implemented a large subset of ANSI X.364. Among its major upgrades was a number of international character sets, as well as the ability to define new character sets.

VT420 Computer terminal from Digital Equipment Corporation

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.

Sixel

Sixel, short for "six pixels", is a bitmap graphics format supported by terminals and printers from DEC. It consists of a pattern six pixels high and one wide, resulting in 64 possible patterns. Each possible pattern is assigned an ASCII character, making the sixels easy to transmit on 7-bit serial links.

VT520 Computer terminal from Digital Equipment Corporation

The VT520 is an ANSI standard computer terminal introduced by Digital Equipment Corporation (DEC) in 1993 and 1994. The VT520 is a multi-session monochrome text-only terminal with a built-in 14" monitor. The VT510 was a single-session version, while the VT525 added color support and used a separate external monitor.

The National Replacement Character Set (NRCS) was a feature supported by later models of Digital's (DEC) computer terminal systems, starting with the VT200 series in 1983. NRCS allowed individual characters from one character set to be replaced by one from another set, allowing the construction of different character sets on the fly. It was used to customize the character set to different local languages, without having to change the terminal's ROM for different countries, or alternately, include many different sets in a larger ROM. Many 3rd party terminals and terminal emulators supporting VT200 codes also supported NRCS.

VT320 Computer terminal from Digital Equipment Corporation

The VT320 was an ANSI standard computer terminal introduced by Digital Equipment Corporation (DEC) in 1987. The VT320 was the text-only version, while the VT330 added monochrome ReGIS, Sixel and Tektronix 4010 graphics, and the VT340 added color.

Code page 1101, also known as CP1101, is an IBM code page number assigned to the UK variant of DEC's National Replacement Character Set (NRCS). The 7-bit character set was introduced for DEC's computer terminal systems, starting with the VT200 series in 1983, but is also used by IBM for their DEC emulation. Similar but not identical to the series of ISO 646 character sets, the character set is a close derivation from ASCII with only code point 0x23 differing.

Code page 1107, also known as CP1107, is an IBM code page number assigned to the alternate Denmark/Norway variant of DEC's National Replacement Character Set (NRCS). The 7-bit character set was introduced for DEC's computer terminal systems, starting with the VT200 series in 1983, but is also used by IBM for their DEC emulation. Similar but not identical to the series of ISO 646 character sets, the character set is a close derivation from ASCII with only six code points differing.

Code page 1103, also known as CP1103, or SF7DEC, is an IBM code page number assigned to the Finnish variant of DEC's National Replacement Character Set (NRCS). The 7-bit character set was introduced for DEC's computer terminal systems, starting with the VT200 series in 1983, but is also used by IBM for their DEC emulation. Similar but not identical to the series of ISO 646 character sets, the character set is a close derivation from ASCII with only nine code points differing.

Code page 1106, also known as CP1106 or S7DEC, is an IBM code page number assigned to the Swedish variant of DEC's National Replacement Character Set (NRCS). The 7-bit character set was introduced for DEC's computer terminal systems, starting with the VT200 series in 1983, but is also used by IBM for their DEC emulation. Similar but not identical to the series of ISO 646 character sets, the character set is a close derivation from ASCII with only ten code points differing.

Code page 1104, also known as CP1104, F7DEC, ISO-IR-025 or NF Z 62-010 (1973) is an IBM code page number assigned to the French variant of DEC's National Replacement Character Set (NRCS). The 7-bit character set was introduced for DEC's computer terminal systems, starting with the VT200 series in 1983, but it is also used by IBM for their DEC emulation.

Code page 1020, also known as CP1020, is an IBM code page number assigned to the French-Canadian variant of DEC's National Replacement Character Set (NRCS). The 7-bit character set was introduced for DEC's computer terminal systems, starting with the VT200 series in 1983, but is also used by IBM for their DEC emulation. Similar but not identical to the series of ISO 646 character sets, the character set is a close derivation from ASCII with only ten code points differing.

Code page 1021, also known as CP1021 or CH7DEC, is an IBM code page number assigned to the Swiss variant of DEC's National Replacement Character Set (NRCS). The 7-bit character set was introduced for DEC's computer terminal systems, starting with the VT200 series in 1983, but is also used by IBM for their DEC emulation. Similar but not identical to the series of ISO 646 character sets, the character set is a close derivation from ASCII with only twelve code points differing.

Code page 1023, also known as CP1023 or E7DEC, is an IBM code page number assigned to the Spanish variant of DEC's National Replacement Character Set (NRCS). The 7-bit character set was introduced for DEC's computer terminal systems, starting with the VT200 series in 1983, but is also used by IBM for their DEC emulation. Similar but not identical to the series of ISO 646 character sets, the character set is a close derivation from ASCII with only eight code points differing.

Code page 1287, also known as CP1287, DEC Greek (8-bit) and EL8DEC, is one of the code pages implemented for the VT220 terminals. It supports the Greek language.

Code page 1288, also known as CP1288, DEC Turkish (8-bit) and TR8DEC, is one of the code pages implemented for the VT220 terminals. It supports the Turkish language.

DEC Special Graphics

DEC Special Graphics is a 7-bit character set developed by Digital Equipment Corporation. This was used very often to draw boxes on the VT100 video terminal and the many emulators, and used by bulletin board software. The designation escape sequence ESC ( 0 switched the codes for lower-case ASCII letters to draw this set, and the sequence ESC ( B switched back. IBM calls it Code page 1090.

DEC Technical (TCS) is a 7-bit character set developed by Digital Equipment Corporation.

The VT100 code page is a character encoding used to represent text on the Classic Mac OS for compatibility with the VT100 terminal. It encodes 256 characters, the first 128 of which are identical to ASCII, with the remaining characters including mathematical symbols, diacritics, and additional punctuation marks. It is suitable for English and several other Western languages. It is similar to Mac OS Roman, but includes all characters in ISO 8859-1 except for the currency sign, the no-break space, and the soft hyphen. It also includes all characters in DEC Special Graphics, except for the new line and no-break space controls. The VT100 encoding is only used on the VT100 font on the Classic Mac OS, and is not an official Mac OS character encoding.

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