Кодовая страница 866: История и варианты русской кодировки

Computer character set for Russian

Code page 866 (CCSID 866) (CP 866, "DOS Cyrillic Russian") The code page was widely used during the DOS era because it preserves all of the pseudographic symbols of code page 437 (unlike the "Main code page" or Code page 855) and maintains alphabetic order (although non contiguously) of Cyrillic letters (unlike KOI8 R). Initially this encoding was only available in the Russian version of MS DOS 4.01 (1990), but with MS DOS 6.22 it became available in any language version. The WHATWG Encoding Standard, which specifies the character encodings permitted in HTML5 which compliant browsers must support, includes Code page 866. It is the only single byte encoding listed which is not named as an ISO 8859 part, Mac OS specific encoding, Microsoft Windows specific encoding (Windows 874 or Windows 125x) or KOI 8 variant. Two very similar but not identical encodings are standardised in GOST R 34.303 92 as KOI 8 N1 and KOI 8 N2 (not to be confused with the original KOI 8).

Each non ASCII character is shown with its equivalent Unicode code point. The first half (code points 0–127) of this table is the same as that of code page 437 (q. v.).

There existed a few variants of the code page, but the differences were mostly in the last 16 code points (240–255).

An unofficial variant with code points 240–255 identical to code page 437. However, the letter Ёё is usually placed at 240 and 241. This version supports only Russian and Bulgarian. The differing row is shown below.

The GOST R 34.303 92 standard defines two variants, KOI 8 N1 and KOI 8 N2. These are not to be confused with the KOI 8 encoding, which they do not adhere to.

Ukrainian standard RST 2018 91 is designated by IBM as Code page 1125 (CCSID 1125), abbreviated CP1125, and also known as CP866U, CP866NAV or RUSCII. It matches the original Alternative code page for all points except for F2hex through F9hex inclusive, which are replaced with Ukrainian letters. matches code page 866 for all points except for F8hex, F9hex, and FChex through FEhex inclusive, which are replaced with otherwise missing Ukrainian and Belarusian letters, in the process displacing the bullet character (∙) from F9hex to FEhex. The differing rows are shown below. Also, the so called CP 866ukr code page is a modified version of CP866 with the replacement of Ўў by Іі. Unlike CP1125, it maintains full compatibility of Ukrainian letters with CP866, although Ґґ is missing. It is not included in the standard Windows distributions, but some users install a home made patch that allows using this encoding to work in command line programs (such as FAR Manager) with filenames containing the Cyrillic Іі.

IBM code page/CCSID 808 is a variant of code page/CCSID 866; with the euro sign (€, U+20AC) in position FDhex, replacing the universal currency sign (¤). IBM code page/CCSID 848 is a variant of code page/CCSID 1125 with the euro sign at FDhex, replacing ¤. IBM code page/CCSID 849 is a variant of code page/CCSID 1131 with the euro sign at FBhex, replacing ¤.

An unofficial modification used in software developed by Michael Lehner and Peter R. Czech. It replaces three mathematic symbols with guillemets and the section sign which are commonly used in the Russian language. (Lehner and Czech created a number of alternative character sets for other European languages as well, including one based on CWI 2 for Hungarian, a Kamenicky based one for Czech and Slovak, a Mazovia variant for Polish and a seemingly unique encoding for Lithuanian. The modified row is shown below.

A Latvian variant, supported by Star printers and FreeDOS, is code page 3012. This encoding is nicknamed "RusLat".

Before Microsoft's final code page for Russian MS DOS 4.01 was registered with IBM by Franz Rau of Microsoft as CP866 in January 1990, draft versions of it developed by Yuri Starikov (Юрий Стариков) of Dialogue were still called code page 900 internally. While the documentation was corrected to reflect the new name before the release of the product, sketches of earlier draft versions still named code page 900 and without Ukrainian and Belarusian letters, which had been added in autumn 1989, were published in the Russian press in 1990. Code page 900 slipped through into the distribution of the Russian MS DOS 5.0 LCD. CPI codepage information file.