{"id":32463,"date":"2019-10-31T21:47:12","date_gmt":"2019-10-31T18:47:12","guid":{"rendered":"https:\/\/prohoster.info\/blog\/kak-i-zachem-chitat-datashity-esli-mikrokontrollery-vashe-hobbi\/"},"modified":"2019-10-31T21:47:12","modified_gmt":"2019-10-31T18:47:12","slug":"kak-i-zachem-chitat-datashity-esli-mikrokontrollery-vashe-hobbi","status":"publish","type":"post","link":"https:\/\/prohoster.info\/cs\/blog\/news\/kak-i-zachem-chitat-datashity-esli-mikrokontrollery-vashe-hobbi","title":{"rendered":"Jak a pro\u010d \u010d\u00edst datasheety, pokud jsou mikro\u0159adi\u010de va\u0161\u00edm kon\u00ed\u010dkem","gt_translate_keys":[{"key":"rendered","format":"text"}]},"content":{"rendered":"

\"Jak<\/p>\n

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Mikroelektronika se stala m\u00f3dn\u00edm kon\u00ed\u010dkem posledn\u00edch let d\u00edky kouzeln\u00e9mu Arduinu. Ale ouha: p\u0159i dostate\u010dn\u00e9m z\u00e1jmu se DigitalWrite() rychle p\u0159ekon\u00e1 a co d\u00e1l \u2013 to u\u017e nen\u00ed \u00fapln\u011b jasn\u00e9. V\u00fdvoj\u00e1\u0159i Arduina vynalo\u017eili zna\u010dn\u00e9 \u00fasil\u00ed na sn\u00ed\u017een\u00ed prahu vstupu do sv\u00e9ho ekosyst\u00e9mu, ale za jeho hranicemi se st\u00e1le rozkl\u00e1d\u00e1 temn\u00fd les drsn\u00e9 elektroniky, kter\u00fd je pro nad\u0161ence t\u011b\u017eko p\u0159\u00edstupn\u00fd.<\/p>\n

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Nap\u0159\u00edklad datasheety. P\u0159ipad\u00e1 to, \u017ee v nich je v\u0161echno, co pot\u0159ebujete \u2013 sta\u010d\u00ed vz\u00edt a pou\u017e\u00edvat. Ale jejich auto\u0159i se nezdaj\u00ed, \u017ee by si kladli za c\u00edl popularizovat mikro\u0159adi\u010de; n\u011bkdy to vypad\u00e1<\/em>, \u017ee \u00famysln\u011b zneu\u017e\u00edvaj\u00ed nejasn\u00e9 term\u00edny a zkratky p\u0159i popisu jednoduch\u00fdch v\u011bc\u00ed, aby maxim\u00e1ln\u011b zm\u00e1tli nev\u011bdom\u00e9ho. Ale nen\u00ed to tak zl\u00e9, s trochou snahy se lar\u010d\u00edk otev\u0159e.<\/p>\n

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V tomto \u010dl\u00e1nku se pod\u011bl\u00edm o zku\u0161enosti \u0433\u0443\u043c\u0430\u043d\u0438\u0442\u0430\u0440\u0438\u044f s datasheety pro hobby \u00fa\u010dely. Text je ur\u010den pro ty, kte\u0159\u00ed vyrostli z leg\u00edn Arduina, a p\u0159edpokl\u00e1d\u00e1 ur\u010dit\u00e9 znalosti o principu fungov\u00e1n\u00ed mikro\u0159adi\u010d\u016f.<\/p>\n

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Za\u010dnu s tradi\u010dn\u00edm<\/p>\n

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Blik\u00e1n\u00ed LED diodou na Arduinu<\/h3>\n

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A hned k\u00f3d:<\/p>\n

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void setup() {\nDDRB |= (1<<5);\n}\n\nvoid loop() {\nPINB = (1<<5);\nfor (volatile uint32_t k=0; k<100000; k++);\n}<\/code><\/pre>\n
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\u201eCo to je? \u2013 zept\u00e1 se zku\u0161en\u00fd \u010dten\u00e1\u0159. \u2013 Pro\u010d n\u011bco p\u00ed\u0161e\u0161 do vstupn\u00edho registru PINB? V\u017edy\u0165 je to jen pro \u010dten\u00ed!\u201c Opr\u00e1vn\u011bn\u011b, dokumentace Arduina<\/a><\/noindex>, jako v\u011bt\u0161ina vzd\u011bl\u00e1vac\u00edch \u010dl\u00e1nk\u016f na internetu, tvrd\u00ed, \u017ee tento registr je pouze pro \u010dten\u00ed. I j\u00e1 jsem si to myslel, dokud jsem znovu nep\u0159e\u010detl datov\u00fd list<\/a><\/noindex> datasheet k Atmega328p, abych p\u0159ipravil tento \u010dl\u00e1nek. A tam:<\/p>\n
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\"Jak<\/p>\n
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To je relativn\u011b nov\u00e1 funkce, na Atmega8 nebyla a ne v\u0161ichni o n\u00ed v\u00ed nebo ji nezmi\u0148uj\u00ed z hlediska zp\u011btn\u00e9 kompatibility. Ale je to docela dobr\u00e9 pro p\u0159edveden\u00ed my\u0161lenky, \u017ee datasheety je t\u0159eba \u010d\u00edst, abyste vyu\u017eili v\u0161echny mo\u017enosti \u010dipu, v\u010detn\u011b m\u00e9n\u011b zn\u00e1m\u00fdch. A to nen\u00ed jedin\u00fd d\u016fvod.<\/p>\n
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Pro\u010d je\u0161t\u011b \u010d\u00edst datasheety<\/h2>\n
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Obvykle se nad\u0161enci do Arduina, pot\u00e9 co si dostate\u010dn\u011b vyhraj\u00ed se sv\u011btly a funkcemi AnalogWrite, za\u010dnou p\u0159ipojovat k desce nejr\u016fzn\u011bj\u0161\u00ed moduly a \u010dipy, pro kter\u00e9 u\u017e existuj\u00ed napsan\u00e9 knihovny. D\u0159\u00edve nebo pozd\u011bji v\u0161ak naraz\u00ed na knihovnu, kter\u00e1 nefunguje tak, jak by m\u011bla. Tehdy se nad\u0161enec pust\u00ed do jej\u00edho vylep\u0161ov\u00e1n\u00ed a tam...<\/p>\n
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Tam se d\u011bje n\u011bco naprosto nepochopiteln\u00e9ho, a proto mus\u00edm vyrazit na Google, \u010d\u00edst nespo\u010det tutori\u00e1l\u016f, stahovat kousky n\u011b\u010d\u00edho u\u017eite\u010dn\u00e9ho k\u00f3du a nakonec si vybojovat sv\u00e9. To d\u00e1v\u00e1 siln\u00fd pocit \u00fasp\u011bchu, ale ve skute\u010dnosti proces p\u0159ipom\u00edn\u00e1 vynal\u00e9z\u00e1n\u00ed kola pomoc\u00ed reverzn\u00edho in\u017een\u00fdrstv\u00ed motocyklu. A pochopen\u00ed, jak toto kolo funguje, se nijak nezlep\u0161uje. V\u00edm to, proto\u017ee jsem se t\u00edm zab\u00fdval docela dlouho.<\/p>\n
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Kdybych m\u00edsto tohoto vzru\u0161uj\u00edc\u00edho kon\u00ed\u010dka str\u00e1vil p\u00e1r dn\u00ed studiem dokumentace k Atmega328, u\u0161et\u0159il bych obrovsk\u00e9 mno\u017estv\u00ed \u010dasu. Nakonec je to docela jednoduch\u00fd mikro\u0159adi\u010d.<\/p>\n
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T\u00edm p\u00e1dem je nutn\u00e9 \u010d\u00edst datasheety alespo\u0148 proto, abychom m\u011bli p\u0159edstavu o tom, jak mikro\u0159adi\u010d vlastn\u011b funguje a co v\u0161echno um\u00ed. A je\u0161t\u011b:<\/p>\n
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