{"id":12423,"date":"2014-03-11T22:52:38","date_gmt":"2014-03-11T21:52:38","guid":{"rendered":"http:\/\/www.eurosource.se\/akhe\/wordpress\/?p=12423"},"modified":"2015-10-26T09:43:02","modified_gmt":"2015-10-26T08:43:02","slug":"usb","status":"publish","type":"post","link":"https:\/\/www.akehedman.se\/wordpress\/?p=12423","title":{"rendered":"USB"},"content":{"rendered":"

\"usb\"<\/a><\/p>\n

Du s\u00e4tter in den d\u00e4r USB-kabeln i din dator och har du bara drivaren eller om dit operativsystem redan har den inbyggd s\u00e5 liksom bara fungerar det. I alla fall f\u00f6r det mesta och om du sitter p\u00e5 en “normal” maskin.<\/p>\n

Om folk visste om allt som h\u00e4nder n\u00e4r man s\u00e4tter i den d\u00e4r kabeln s\u00e5 skulle man bli betydligt mer tacksamma f\u00f6r det d\u00e4r “fungerar”. Det \u00e4r n\u00e4mligen en j\u00e4kla massa prat i den d\u00e4r kabeln innan saker och ting \u00e4r p\u00e5 plats och “det fungerar”. Har suttit en vecka nu och implementerat USB \u00e5t en kund och de sista dagarna har jag letat ett fel som inte varit helt sj\u00e4lvklart att hitta. H\u00e5rdvara s\u00e5klart. Som mjukvarusnubbe blir man alltid glad n\u00e4r man hittar ett fel p\u00e5 h\u00e5rdvaran s\u00e5 att man kan skylla p\u00e5 h\u00e5rdvarukonstrukt\u00f6ren. Men jag har s\u00e5klart varit med tillr\u00e4ckligt l\u00e4nge f\u00f6r att s\u00e4kra det d\u00e4r v\u00e4ldigt noga innan jag riktar beskyllningarna \u00e5t det h\u00e5llet. Oftast \u00e4r det n\u00e4mligen vi mjukvarusnubbar som st\u00e4ller till n\u00e5got (l\u00e4s st\u00e5r f\u00f6r felen).<\/p>\n

S\u00e5 i tre dar har jag letat den h\u00f6r buggen. Testat allt man kan t\u00e4nka sig och systematiskt g\u00e5tt igenom koden flera g\u00e5nger. Det t\u00e4r p\u00e5 en det d\u00e4r. Men inte hitta n\u00e5got allts\u00e5. S\u00e5 idag pl\u00f6ja manualer. Checka upp h\u00e5rdvaran. Det \u00e4r n\u00e5gra tusen sidor f\u00f6r den h\u00e4r processorn s\u00e5 det \u00e4r om\u00f6jligt att ha koll p\u00e5 allt men s\u00e5 nu p\u00e5 eftermiddagen idag s\u00e5 hittade jag problemet. En sk\u00f6n k\u00e4nsla sprider sig i kroppen n\u00e4r man kan verifiera att det var det man trodde som var felet. Allt blir roligt igen och man kan forts\u00e4tta med projektet. I alla fall tills man hittar n\u00e4sta bugg och skall f\u00f6rs\u00f6ka finna en l\u00f6sning p\u00e5 den.<\/p>\n

N\u00e4sta g\u00e5ng du stoppar i en USB-sladd, s\u00e4nd en tanke till dem som gjort att det fungerar. Eller skit i det f\u00f6rresten, f\u00f6r dom har redan f\u00e5tt sitt tack i och med att det just fungerar. Det \u00e4r det vi lever p\u00e5 vi inb\u00e4ddade snubbar. M\u00e4rks inte det vi konstruerat s\u00e5 \u00e4r allt OK och vi har lyckats.<\/p>\n","protected":false},"excerpt":{"rendered":"

Du s\u00e4tter in den d\u00e4r USB-kabeln i din dator och har du bara drivaren eller om dit operativsystem redan har den inbyggd s\u00e5 liksom bara fungerar det. I alla fall f\u00f6r det mesta och om du sitter p\u00e5 en “normal” maskin. Om folk visste om allt som h\u00e4nder n\u00e4r man s\u00e4tter i den d\u00e4r kabeln […]<\/p>\n","protected":false},"author":24,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_crdt_document":"","jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":true,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2}},"categories":[24],"tags":[],"class_list":["post-12423","post","type-post","status-publish","format-standard","hentry","category-betraktelser"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"jetpack_likes_enabled":true,"jetpack-related-posts":[{"id":51227,"url":"https:\/\/www.akehedman.se\/wordpress\/?p=51227","url_meta":{"origin":12423,"position":0},"title":"Strul","author":"\u00c5ke Hedman","date":"2026-02-19","format":false,"excerpt":"Photo by Polina Zimmerman on Pexels.com B\u00f6rjar dagen med att utvecklingsdatorn inte startar upp. Beter sig V\u00c4LDIGT underligt. Det tar en stund att hitta felet. Min utvecklingskrets som har JTAG support inbyggt och kopplar upp till datorn med USB har f\u00e5tt hicka. N\u00e4r den kabeln \u00e4r borta s\u00e5 fungerar allt\u2026","rel":"","context":"In "Betraktelser & Ber\u00e4ttelse"","block_context":{"text":"Betraktelser & Ber\u00e4ttelse","link":"https:\/\/www.akehedman.se\/wordpress\/?cat=24"},"img":{"alt_text":"black smartphone displaying error","src":"https:\/\/i0.wp.com\/www.akehedman.se\/wordpress\/wp-content\/uploads\/2026\/02\/pexels-photo-3747139.jpeg?resize=350%2C200&ssl=1","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/www.akehedman.se\/wordpress\/wp-content\/uploads\/2026\/02\/pexels-photo-3747139.jpeg?resize=350%2C200&ssl=1 1x, https:\/\/i0.wp.com\/www.akehedman.se\/wordpress\/wp-content\/uploads\/2026\/02\/pexels-photo-3747139.jpeg?resize=525%2C300&ssl=1 1.5x, https:\/\/i0.wp.com\/www.akehedman.se\/wordpress\/wp-content\/uploads\/2026\/02\/pexels-photo-3747139.jpeg?resize=700%2C400&ssl=1 2x"},"classes":[]},{"id":11413,"url":"https:\/\/www.akehedman.se\/wordpress\/?p=11413","url_meta":{"origin":12423,"position":1},"title":"Felk\u00e4llor","author":"\u00c5ke Hedman","date":"2013-12-13","format":false,"excerpt":"Det \u00e4r alltid de enkla grejerna som f\u00e4ller en. Man kan hitta p\u00e5 hundratjugofyra saker som man kan t\u00e4nka sig det \u00e4r fel p\u00e5 och grubbla och grubbla och grubbla och sen n\u00e4r man g\u00e5r upp och \u00e4ter lunch v\u00e4cks en s\u00e5dan d\u00e4r liten tanke i huvudet. Det kanske \u00e4r\u2026","rel":"","context":"In "Betraktelser & Ber\u00e4ttelse"","block_context":{"text":"Betraktelser & Ber\u00e4ttelse","link":"https:\/\/www.akehedman.se\/wordpress\/?cat=24"},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":20926,"url":"https:\/\/www.akehedman.se\/wordpress\/?p=20926","url_meta":{"origin":12423,"position":2},"title":"Uppfinnarhj\u00e4rna","author":"\u00c5ke Hedman","date":"2016-07-06","format":false,"excerpt":"Jod\u00e5 jag vaknar klockan tre. Dvs huvudet vaknar. Kroppen har inte gjort det. Vill ligga kvar men vad g\u00f6r man om huvudet s\u00e4tter raketfart och funderar och t\u00e4nker, som kropp \u00e5ker man bara med. Och nej, det hj\u00e4lper inte att t\u00e4nka rationellt heller. Den d\u00e4r rationella t\u00e4nkande delen, som \u00e4r\u2026","rel":"","context":"In "Betraktelser & Ber\u00e4ttelse"","block_context":{"text":"Betraktelser & Ber\u00e4ttelse","link":"https:\/\/www.akehedman.se\/wordpress\/?cat=24"},"img":{"alt_text":"images","src":"https:\/\/i0.wp.com\/www.akehedman.se\/wordpress\/wp-content\/uploads\/2016\/07\/images.jpg?resize=350%2C200","width":350,"height":200},"classes":[]},{"id":25372,"url":"https:\/\/www.akehedman.se\/wordpress\/?p=25372","url_meta":{"origin":12423,"position":3},"title":"Brandtillbud","author":"\u00c5ke Hedman","date":"2017-09-13","format":false,"excerpt":"Jod\u00e5, Ljusdal, skall upplevas ibland. Nejd\u00e5, inget fel p\u00e5 Ljusdal. K har m\u00f6te. Jag g\u00e5r runt sj\u00f6n, sitter p\u00e5 biblioteket och tar sen en fika p\u00e5 Stora Coop - japp det heter s\u00e5 och \u00e4r v\u00e4ldigt svart. Cappuccino och princessbakelse. Gott liksom. Men man skall sk\u00e4mmas bort. F\u00e5r h\u00f6ra senare\u2026","rel":"","context":"In "Betraktelser & Ber\u00e4ttelse"","block_context":{"text":"Betraktelser & Ber\u00e4ttelse","link":"https:\/\/www.akehedman.se\/wordpress\/?cat=24"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/www.akehedman.se\/wordpress\/wp-content\/uploads\/2017\/09\/IMG_20170913_102332067-1024x768.jpg?resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/www.akehedman.se\/wordpress\/wp-content\/uploads\/2017\/09\/IMG_20170913_102332067-1024x768.jpg?resize=350%2C200 1x, https:\/\/i0.wp.com\/www.akehedman.se\/wordpress\/wp-content\/uploads\/2017\/09\/IMG_20170913_102332067-1024x768.jpg?resize=525%2C300 1.5x"},"classes":[]},{"id":20738,"url":"https:\/\/www.akehedman.se\/wordpress\/?p=20738","url_meta":{"origin":12423,"position":4},"title":"Jag skall bli s\u00e4lgkramare","author":"\u00c5ke Hedman","date":"2016-06-20","format":false,"excerpt":"Morgon. Sommar. Om man vaknar f\u00f6rst i familjen. Tystnaden. Ett hus som sover. Man sj\u00e4lv \u00e4r vaken. Matar katter. \u00c4ter frukost. Duschar. Brygger te. Sitter d\u00e4r ett tag. Ja en av de d\u00e4r sakerna jag tycker om med sommaren. Det \u00e4r liksom bara f\u00e5glarna och jag. I hela v\u00e4rlden. Ja,\u2026","rel":"","context":"In "Betraktelser & Ber\u00e4ttelse"","block_context":{"text":"Betraktelser & Ber\u00e4ttelse","link":"https:\/\/www.akehedman.se\/wordpress\/?cat=24"},"img":{"alt_text":"12912461_878521785610792_2051855321_n","src":"https:\/\/i0.wp.com\/www.akehedman.se\/wordpress\/wp-content\/uploads\/2016\/06\/12912461_878521785610792_2051855321_n.jpg?resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/www.akehedman.se\/wordpress\/wp-content\/uploads\/2016\/06\/12912461_878521785610792_2051855321_n.jpg?resize=350%2C200 1x, https:\/\/i0.wp.com\/www.akehedman.se\/wordpress\/wp-content\/uploads\/2016\/06\/12912461_878521785610792_2051855321_n.jpg?resize=525%2C300 1.5x"},"classes":[]},{"id":16612,"url":"https:\/\/www.akehedman.se\/wordpress\/?p=16612","url_meta":{"origin":12423,"position":5},"title":"Guldreserven","author":"\u00c5ke Hedman","date":"2015-02-19","format":false,"excerpt":"Den sista av systrarna d\u00f6r. Hon vill d\u00f6 s\u00e5 det \u00e4r v\u00e4l bara r\u00e4ttvist att det till slut sker. Det \u00e4r inte l\u00e4tt att bli gammal. Man blir livstr\u00f6tt till slut. Kusin fr\u00e5n \u00d6land ringer och meddelar. Ringer till K, inte till mig. Men inget att s\u00e4ga om det. 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