{"id":96211,"date":"2020-10-09T07:42:43","date_gmt":"2020-10-09T05:42:43","guid":{"rendered":"https:\/\/prohoster.info\/blog\/administrirovanie\/pochemu-v-ebcdic-bukvy-idut-ne-podryad"},"modified":"2020-10-09T07:42:43","modified_gmt":"2020-10-09T05:42:43","slug":"pochemu-v-ebcdic-bukvy-idut-ne-podryad","status":"publish","type":"post","link":"https:\/\/prohoster.info\/cs\/blog\/administrirovanie\/pochemu-v-ebcdic-bukvy-idut-ne-podryad","title":{"rendered":"Pro\u010d v EBCDIC jdou p\u00edsmena za sebou?","gt_translate_keys":[{"key":"rendered","format":"text"}]},"content":{"rendered":"

Standard ASCII byl p\u0159ijat v roce 1963, a dnes je sotva n\u011bkdo, kdo by pou\u017e\u00edval k\u00f3dov\u00e1n\u00ed, jeho\u017e prvn\u00edch 128 znak\u016f by se li\u0161ilo od ASCII. Nicm\u00e9n\u011b, a\u017e do konce minul\u00e9ho stolet\u00ed se aktivn\u011b pou\u017e\u00edval EBCDIC \u2013 standardn\u00ed k\u00f3dov\u00e1n\u00ed pro IBM mainframy a jejich sov\u011btsk\u00e9 klony \u0415\u0421 \u042d\u0412\u041c. EBCDIC z\u016fst\u00e1v\u00e1 hlavn\u00edm k\u00f3dov\u00e1n\u00edm v z\/OS \u2013 standardn\u00ed opera\u010dn\u00ed syst\u00e9m pro modern\u00ed IBM Z mainframy.<\/p>\n

Co okam\u017eit\u011b ude\u0159\u00ed do o\u010d\u00ed p\u0159i pohledu na EBCDIC \u2013 je to, \u017ee p\u00edsmena nejsou uspo\u0159\u00e1d\u00e1na postupn\u011b: mezi I<\/code> a J<\/code> a mezi R<\/code> a S<\/code> z\u016fstaly nevyu\u017eit\u00e9 pozice (na \u0415\u0421 \u042d\u0412\u041c byly v t\u011bchto mezer\u00e1ch rozm\u00edst\u011bny<\/a><\/noindex> znaky cyrilice). Komu mohlo p\u0159ij\u00edt na mysl k\u00f3dovat p\u00edsmena s nerovn\u00fdmi mezerami mezi sousedn\u00edmi p\u00edsmeny?<\/p>\n

\"Pro\u010d<\/p>\n

Samotn\u00fd n\u00e1zev EBCDIC (\u00bbExtended BCDIC\u00ab) nazna\u010duje, \u017ee tato k\u00f3dov\u00e1n\u00ed \u2013 na rozd\u00edl od ASCII \u2013 vznikla ne z ni\u010deho, ale na z\u00e1klad\u011b \u0161estim\u00edstn\u00e9ho k\u00f3dov\u00e1n\u00ed BCDIC, kter\u00e9 se pou\u017e\u00edvalo od IBM 704<\/a><\/noindex> (1954):<\/p>\n

\"Pro\u010d<\/p>\n

P\u0159\u00edm\u00e1 zp\u011btn\u00e1 kompatibilita neexistuje: pohodlnou vlastnost\u00ed BCDIC, ztracenou p\u0159eveden\u00edm na EBCDIC, bylo to, \u017ee \u010d\u00edsl\u016fm 0<\/code>—9<\/code> odpov\u00eddaj\u00ed k\u00f3dy 0-9. Nicm\u00e9n\u011b, mezery o sedmi k\u00f3dech mezi I<\/code> a J<\/code> a osmi k\u00f3dy mezi R<\/code> a S<\/code> v BCDIC u\u017e byly. Kde se vzaly?<\/p>\n

Historie (E)BCDIC za\u010d\u00edn\u00e1 sou\u010dasn\u011b s histori\u00ed IBM \u2013 dlouho p\u0159ed elektronick\u00fdmi po\u010d\u00edta\u010di. IBM vznikla slou\u010den\u00edm \u010dty\u0159 spole\u010dnost\u00ed, z nich\u017e nejtechnologi\u010dt\u011bj\u0161\u00ed byla \u00bbTabulating Machine Company\u00ab, zalo\u017een\u00e1 v roce 1896 Hermanem Hollerithiem \u2013 vyn\u00e1lezcem tabul\u00e1tor\u016f<\/a><\/noindex>. Prvn\u00ed tabul\u00e1tory pouze po\u010d\u00edtaly po\u010det d\u011brovan\u00fdch karet, kter\u00e9 pro\u0161ly ur\u010dit\u00fdm m\u00edstem; ale v roce 1905 Hollerit za\u010dal v\u00fdrobu desetinn\u00fdch<\/em> tabul\u00e1tor\u016f. Ka\u017ed\u00e1 karta pro desetinn\u00fd tabul\u00e1tor se skl\u00e1dala z pol\u00ed libovoln\u00e9 d\u00e9lky, a \u010d\u00edsla zaznamenan\u00e1 v t\u011bchto pol\u00edch v obvykl\u00e9 des\u00edtkov\u00e9 podob\u011b se s\u010d\u00edtala po cel\u00e9 hromad\u011b. Rozd\u011blen\u00ed karty na pole bylo ur\u010dov\u00e1no propojov\u00e1n\u00edm dr\u00e1t\u016f na p\u0159ep\u00ednac\u00ed desce tabul\u00e1toru. Nap\u0159\u00edklad na t\u00e9to d\u011brovan\u00e9 kart\u011b Hollerita, uchov\u00e1van\u00e9<\/a><\/noindex> v Kongresov\u00e9 knihovn\u011b, je jasn\u011b vyra\u017eeno \u010d\u00edslo 23456789012345678, nezn\u00e1mo jak rozd\u011blen\u00e9 na pole:<\/p>\n

\"Pro\u010d<\/p>\n

Nejpozorn\u011bj\u0161\u00ed mohli zaznamenat, \u017ee na kart\u011b Hollerita je 12 \u0159ad pro otvory, a\u010dkoliv pro \u010d\u00edsla sta\u010d\u00ed deset; a v BCDIC se pro ka\u017edou hodnotu dvou vy\u0161\u0161\u00edch bit\u016f pou\u017e\u00edv\u00e1 pouze 12 k\u00f3d\u016f z 16 mo\u017en\u00fdch.<\/p>\n

Samoz\u0159ejm\u011b, \u017ee to nen\u00ed n\u00e1hodn\u00e1 shoda. P\u016fvodn\u011b Hollerith zam\u00fd\u0161lel dal\u0161\u00ed \u0159ady pro \u00bbspeci\u00e1ln\u00ed zna\u010dky\u00ab, kter\u00e9 se nes\u010d\u00edtaly, ale pouze po\u010d\u00edtaly \u2013 jako v nejstar\u0161\u00edch tabul\u00e1torech. (Dnes bychom je nazvali \u00bbbitov\u00fdmi poli\u00ab.) D\u00e1le bylo mo\u017en\u00e9 mezi \u00bbspeci\u00e1ln\u00edmi zna\u010dkami\u00ab nastavit skupinov\u00e9 indik\u00e1tory: pokud bylo p\u0159i tabulaci pot\u0159eba nejen kone\u010dn\u00fdch sou\u010dt\u016f, ale i mezisou\u010dt\u016f, tabul\u00e1tor se zastavil, kdy\u017e zjistil zm\u011bnu kter\u00e9hokoli z group indicators, a oper\u00e1tor musel p\u0159epsat mezisou\u010dty z digit\u00e1ln\u00edch displej\u016f na pap\u00edr, vynulovat tabul\u00e1tor a obnovit tabulaci. Nap\u0159\u00edklad p\u0159i po\u010d\u00edt\u00e1n\u00ed \u00fa\u010detn\u00edch bilanc\u00ed mohla skupina karet odpov\u00eddat jednomu datu nebo jednomu obchodn\u00edmu partnerovi.<\/p>\n

K roku 1920, kdy Hollerith ji\u017e ode\u0161el do d\u016fchodu, se za\u010daly pou\u017e\u00edvat \u00bbtiskov\u00e9 tabul\u00e1tory\u00ab, kter\u00e9 se p\u0159ipojovaly k teletype a mohly samy tisknout mezisou\u010dty, ani\u017e by vy\u017eadovaly z\u00e1sah oper\u00e1tora. Komplexnost nyn\u00ed spo\u010d\u00edvala v ur\u010den\u00ed, k \u010demu se ka\u017ed\u00e9 z vyti\u0161t\u011bn\u00fdch \u010d\u00edsel vztahuje. V roce 1931 se IBM rozhodla pomoc\u00ed \u00bbspeci\u00e1ln\u00edch znak\u016f\u00ab ozna\u010dovat p\u00edsmena: zna\u010dka ve 12. \u0159ad\u011b ozna\u010dovala p\u00edsmeno od A<\/code> do I<\/code>, v 11. \u0159ad\u011b \u2013 od J<\/code> do R<\/code>, v nulov\u00e9 \u2013 od S<\/code> do Z<\/code>. Nov\u00fd \u00bbalfabetick\u00fd tabul\u00e1tor\u00ab mohl tisknout n\u00e1zev ka\u017ed\u00e9 skupiny karet spolu s mezisou\u010dty; p\u0159i\u010dem\u017e nepro\u0161l\u00fd sloupec se stal mezerou mezi znaky. V\u0161imn\u011bte si, \u017ee S<\/code> je ozna\u010deno kombinac\u00ed otvor\u016f 0+2, zat\u00edmco kombinace 0+1 nebyla zpo\u010d\u00e1tku pou\u017e\u00edv\u00e1na ze strachu, \u017ee dva otvory vedle sebe v jednom sloupci mohou zp\u016fsobit mechanick\u00e9 probl\u00e9my ve \u010dte\u010dce.<\/p>\n

\"Pro\u010d<\/p>\n

Nyn\u00ed na tabulku BCDIC m\u016f\u017eete pohl\u00ed\u017eet m\u00edrn\u011b jin\u00fdm pohledem:<\/p>\n

\"Pro\u010d<\/p>\n

S v\u00fdjimkou toho, \u017ee 0 a mezera byly p\u0159esunuty na m\u00edsta, vy\u0161\u0161\u00ed dv\u011b bity ur\u010duj\u00ed \u00bbspeci\u00e1ln\u00ed zna\u010dku\u00ab, kterou od roku 1931 pro\u0161li do d\u011brn\u00e9 karty pro odpov\u00eddaj\u00edc\u00ed znak; a ni\u017e\u0161\u00ed \u010dty\u0159i bity ur\u010duj\u00ed \u010d\u00edslo, kter\u00e9 bylo prot\u00edn\u00e1no v hlavn\u00ed \u010d\u00e1sti karty. Podpora symbol\u016f & - \/<\/code> Byly p\u0159id\u00e1ny do tabul\u00e1tor\u016f IBM ve 30. letech 20. stolet\u00ed, a k\u00f3dov\u00e1n\u00ed t\u011bchto symbol\u016f v BCDIC odpov\u00edd\u00e1 kombinac\u00edm otvor\u016f, kter\u00e9 pro n\u011b byly propichov\u00e1ny. Kdy\u017e byla pot\u0159eba podpora je\u0161t\u011b v\u011bt\u0161\u00edho po\u010dtu symbol\u016f, za\u010daly se jako dodate\u010dn\u00e9 'speci\u00e1ln\u00ed zna\u010dky' propichovat \u0159ady 8 \u2013 tak mohl b\u00fdt v jednom sloupci a\u017e t\u0159i otvory. Tento form\u00e1t d\u011brn\u00fdch \u0161t\u00edtk\u016f z\u016fstal prakticky nezm\u011bn\u011bn a\u017e do konce stolet\u00ed. V SSSR byly zachov\u00e1ny IBMovsk\u00e9 k\u00f3dov\u00e1n\u00ed latinky a interpunkce, a pro p\u00edsmena cyrilice se propichovalo hned n\u011bkolik 'speci\u00e1ln\u00edch zna\u010dek' v \u0159ad\u00e1ch 12, 11, 0 \u2013 ani\u017e by byly omezeny na t\u0159i otvory v jednom sloupci.<\/p>\n

P\u0159i vytv\u00e1\u0159en\u00ed po\u010d\u00edta\u010de IBM 704 se nad k\u00f3dov\u00e1n\u00edm symbol\u016f dlouho nep\u0159em\u00fd\u0161lelo: vzali k\u00f3dov\u00e1n\u00ed, kter\u00e9 se ji\u017e tehdy pou\u017e\u00edvalo na d\u011brn\u00fdch \u0161t\u00edtc\u00edch, a pouze 0 'dali na m\u00edsto'. V roce 1964, p\u0159i p\u0159echodu od BCDIC k EBCDIC, z\u016fstala doln\u00ed \u010dty\u0159i bity ka\u017ed\u00e9ho symbolu beze zm\u011bny, a\u010dkoliv se trochu prom\u00edchaly horn\u00ed bity. Tak form\u00e1t d\u011brn\u00fdch \u0161t\u00edtk\u016f, kter\u00fd si vybral Hollerith na za\u010d\u00e1tku minul\u00e9ho stolet\u00ed, ovlivnil architekturu v\u0161ech po\u010d\u00edta\u010d\u016f IBM, v\u010detn\u011b IBM Z.<\/p>\n

Zdroj: habr.com<\/a> <\/p>","protected":false,"gt_translate_keys":[{"key":"rendered","format":"html"}]},"excerpt":{"rendered":"

\u0421\u0442\u0430\u043d\u0434\u0430\u0440\u0442 ASCII \u0431\u044b\u043b \u043f\u0440\u0438\u043d\u044f\u0442 \u0432 1963, \u0438 \u0441\u0435\u0439\u0447\u0430\u0441 \u0432\u0440\u044f\u0434 \u043b\u0438 \u043a\u0442\u043e-\u043d\u0438\u0431\u0443\u0434\u044c \u0438\u0441\u043f\u043e\u043b\u044c\u0437\u0443\u0435\u0442 \u043a\u043e\u0434\u0438\u0440\u043e\u0432\u043a\u0443, \u043f\u0435\u0440\u0432\u044b\u0435 128 \u0441\u0438\u043c\u0432\u043e\u043b\u043e\u0432 \u043a\u043e\u0442\u043e\u0440\u043e\u0439 \u043e\u0442\u043b\u0438\u0447\u0430\u043b\u0438\u0441\u044c \u0431\u044b \u043e\u0442 ASCII. \u0422\u0435\u043c \u043d\u0435 \u043c\u0435\u043d\u0435\u0435, \u0434\u043e \u043a\u043e\u043d\u0446\u0430 \u043f\u0440\u043e\u0448\u043b\u043e\u0433\u043e \u0432\u0435\u043a\u0430 \u0430\u043a\u0442\u0438\u0432\u043d\u043e \u0438\u0441\u043f\u043e\u043b\u044c\u0437\u043e\u0432\u0430\u043b\u0430\u0441\u044c EBCDIC \u2014 \u0441\u0442\u0430\u043d\u0434\u0430\u0440\u0442\u043d\u0430\u044f \u043a\u043e\u0434\u0438\u0440\u043e\u0432\u043a\u0430 \u0434\u043b\u044f \u043c\u0435\u0439\u043d\u0444\u0440\u0435\u0439\u043c\u043e\u0432 IBM \u0438 \u0438\u0445 \u0441\u043e\u0432\u0435\u0442\u0441\u043a\u0438\u0445 \u043a\u043b\u043e\u043d\u043e\u0432 \u0415\u0421 \u042d\u0412\u041c. EBCDIC \u043e\u0441\u0442\u0430\u0451\u0442\u0441\u044f \u043e\u0441\u043d\u043e\u0432\u043d\u043e\u0439 \u043a\u043e\u0434\u0438\u0440\u043e\u0432\u043a\u043e\u0439 \u0432 z\/OS \u2014 \u0441\u0442\u0430\u043d\u0434\u0430\u0440\u0442\u043d\u043e\u0439 \u041e\u0421 \u0434\u043b\u044f \u0441\u043e\u0432\u0440\u0435\u043c\u0435\u043d\u043d\u044b\u0445 \u043c\u0435\u0439\u043d\u0444\u0440\u0435\u0439\u043c\u043e\u0432 […]<\/p>\n","protected":false,"gt_translate_keys":[{"key":"rendered","format":"html"}]},"author":1,"featured_media":96212,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[688],"tags":[],"class_list":["post-96211","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-administrirovanie"],"aioseo_notices":[],"aioseo_head":"\n\t\t\n\t\n\t\n\t\n\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\n","aioseo_head_json":{"title":"\ud83e\udd47Pro\u010d jsou v EBCDIC p\u00edsmena neuspo\u0159\u00e1d\u00e1na? | ProHoster","description":"Standard ASCII byl p\u0159ijat v roce 1963 a v sou\u010dasnosti sotva n\u011bkdo pou\u017e\u00edv\u00e1 k\u00f3dov\u00e1n\u00ed, jeho\u017e prvn\u00edch 128 symbol\u016f by se li\u0161ilo od ASCII.","canonical_url":"https:\/\/prohoster.info\/cs\/blog\/administrirovanie\/pochemu-v-ebcdic-bukvy-idut-ne-podryad","robots":"max-image-preview:large","keywords":"","webmasterTools":{"miscellaneous":""},"schema":null,"og:locale":"cs_CZ","og:site_name":"ProHoster | \u041a\u0443\u043f\u0438\u0442\u044c \u043d\u0430\u0434\u0435\u0436\u043d\u044b\u0439 \u0445\u043e\u0441\u0442\u0438\u043d\u0433 \u0434\u043b\u044f \u0441\u0430\u0439\u0442\u043e\u0432 \u0441 \u0437\u0430\u0449\u0438\u0442\u043e\u0439 \u043e\u0442 DDoS, VPS VDS \u0441\u0435\u0440\u0432\u0435\u0440\u044b","og:type":"article","og:title":"\ud83e\udd47\u041f\u043e\u0447\u0435\u043c\u0443 \u0432 EBCDIC \u0431\u0443\u043a\u0432\u044b \u0438\u0434\u0443\u0442 \u043d\u0435 \u043f\u043e\u0434\u0440\u044f\u0434? | ProHoster","og:description":"\u0421\u0442\u0430\u043d\u0434\u0430\u0440\u0442 ASCII \u0431\u044b\u043b \u043f\u0440\u0438\u043d\u044f\u0442 \u0432 1963, \u0438 \u0441\u0435\u0439\u0447\u0430\u0441 \u0432\u0440\u044f\u0434 \u043b\u0438 \u043a\u0442\u043e-\u043d\u0438\u0431\u0443\u0434\u044c \u0438\u0441\u043f\u043e\u043b\u044c\u0437\u0443\u0435\u0442 \u043a\u043e\u0434\u0438\u0440\u043e\u0432\u043a\u0443, \u043f\u0435\u0440\u0432\u044b\u0435 128 \u0441\u0438\u043c\u0432\u043e\u043b\u043e\u0432 \u043a\u043e\u0442\u043e\u0440\u043e\u0439 \u043e\u0442\u043b\u0438\u0447\u0430\u043b\u0438\u0441\u044c \u0431\u044b \u043e\u0442 ASCII.","og:url":"https:\/\/prohoster.info\/cs\/blog\/administrirovanie\/pochemu-v-ebcdic-bukvy-idut-ne-podryad","og:image":"https:\/\/prohoster.info\/wp-content\/uploads\/2021\/11\/logo-350.jpg","og:image:secure_url":"https:\/\/prohoster.info\/wp-content\/uploads\/2021\/11\/logo-350.jpg","og:image:width":350,"og:image:height":350,"article:published_time":"2020-10-09T05:42:43+00:00","article:modified_time":"2020-10-09T05:42:43+00:00","article:publisher":"https:\/\/www.facebook.com\/prohoster","article:author":"https:\/\/www.facebook.com\/prohoster"},"aioseo_meta_data":{"post_id":"96211","title":null,"description":null,"keywords":null,"keyphrases":null,"primary_term":null,"canonical_url":null,"og_title":null,"og_description":null,"og_object_type":"default","og_image_type":"default","og_image_url":null,"og_image_width":null,"og_image_height":null,"og_image_custom_url":null,"og_image_custom_fields":null,"og_video":null,"og_custom_url":null,"og_article_section":null,"og_article_tags":null,"twitter_use_og":false,"twitter_card":"default","twitter_image_type":"default","twitter_image_url":null,"twitter_image_custom_url":null,"twitter_image_custom_fields":null,"twitter_title":null,"twitter_description":null,"schema":{"blockGraphs":[],"customGraphs":[],"default":{"data":{"Article":[],"Course":[],"Dataset":[],"FAQPage":[],"Movie":[],"Person":[],"Product":[],"ProductReview":[],"Car":[],"Recipe":[],"Service":[],"SoftwareApplication":[],"WebPage":[]},"graphName":"","isEnabled":true},"graphs":[]},"schema_type":null,"schema_type_options":null,"pillar_content":false,"robots_default":true,"robots_noindex":false,"robots_noarchive":false,"robots_nosnippet":false,"robots_nofollow":false,"robots_noimageindex":false,"robots_noodp":false,"robots_notranslate":false,"robots_max_snippet":null,"robots_max_videopreview":null,"robots_max_imagepreview":"large","priority":null,"frequency":null,"local_seo":null,"seo_analyzer_scan_date":null,"breadcrumb_settings":null,"limit_modified_date":false,"reviewed_by":null,"ai":null,"created":"2021-02-28 10:48:22","updated":"2022-10-03 07:13:05","focus_keyword":null,"additional_keywords":null,"truseo_locale":null},"gt_translate_keys":[{"key":"link","format":"url"}],"_links":{"self":[{"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/posts\/96211","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/comments?post=96211"}],"version-history":[{"count":0,"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/posts\/96211\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/media\/96212"}],"wp:attachment":[{"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/media?parent=96211"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/categories?post=96211"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/tags?post=96211"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}