{"id":3917,"date":"2021-03-28T22:42:33","date_gmt":"2021-03-28T20:42:33","guid":{"rendered":"https:\/\/entropie.org\/3615\/?p=3917"},"modified":"2021-04-18T21:47:38","modified_gmt":"2021-04-18T19:47:38","slug":"enregistreur-de-donnees-c02-temperature-humidite","status":"publish","type":"post","link":"https:\/\/entropie.org\/3615\/index.php\/2021\/03\/28\/enregistreur-de-donnees-c02-temperature-humidite\/","title":{"rendered":"Enregistreur de donn\u00e9es avec Arduino Nano :  C02, Temp\u00e9rature, Humidit\u00e9"},"content":{"rendered":"<p><a href=\"https:\/\/entropie.org\/3615\/wp-content\/uploads\/2021\/03\/graphique.png\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/entropie.org\/3615\/wp-content\/uploads\/2021\/03\/graphique.png\" alt=\"\" width=\"640\" height=\"480\" class=\"alignnone size-full wp-image-4014\" srcset=\"https:\/\/entropie.org\/3615\/wp-content\/uploads\/2021\/03\/graphique.png 640w, https:\/\/entropie.org\/3615\/wp-content\/uploads\/2021\/03\/graphique-300x225.png 300w\" sizes=\"(max-width: 709px) 85vw, (max-width: 909px) 67vw, (max-width: 984px) 61vw, (max-width: 1362px) 45vw, 600px\" \/><\/a><\/p>\n<p>J&rsquo;ai mis le code source de mon capteur de CO2 (\u00e9galement enregistreur de donn\u00e9es) sur <a href=\"https:\/\/github.com\/eserandour\/NanoValise\" rel=\"noopener\" target=\"_blank\">GitHub<\/a>. Un fichier que j&rsquo;ai \u00e9crit en Python permet de r\u00e9cup\u00e9rer les donn\u00e9es et de tracer automatiquement la courbe du taux de CO2 en appuyant sur un seul bouton (sur <a href=\"https:\/\/github.com\/eserandour\/NanoValise\/blob\/main\/NanoValise_Recuperation.py\" rel=\"noopener\" target=\"_blank\">GitHub<\/a> \u00e9galement).<\/p>\n<p><a href=\"https:\/\/entropie.org\/3615\/wp-content\/uploads\/2021\/04\/DSC_0934-1600x1062-1.jpg\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/entropie.org\/3615\/wp-content\/uploads\/2021\/04\/DSC_0934-1600x1062-1-1024x680.jpg\" alt=\"\" width=\"840\" height=\"558\" class=\"alignnone size-large wp-image-4042\" srcset=\"https:\/\/entropie.org\/3615\/wp-content\/uploads\/2021\/04\/DSC_0934-1600x1062-1-1024x680.jpg 1024w, https:\/\/entropie.org\/3615\/wp-content\/uploads\/2021\/04\/DSC_0934-1600x1062-1-300x199.jpg 300w, https:\/\/entropie.org\/3615\/wp-content\/uploads\/2021\/04\/DSC_0934-1600x1062-1-768x510.jpg 768w, https:\/\/entropie.org\/3615\/wp-content\/uploads\/2021\/04\/DSC_0934-1600x1062-1-1536x1020.jpg 1536w, https:\/\/entropie.org\/3615\/wp-content\/uploads\/2021\/04\/DSC_0934-1600x1062-1-1200x797.jpg 1200w, https:\/\/entropie.org\/3615\/wp-content\/uploads\/2021\/04\/DSC_0934-1600x1062-1.jpg 1600w\" sizes=\"(max-width: 709px) 85vw, (max-width: 909px) 67vw, (max-width: 1362px) 62vw, 840px\" \/><\/a><\/p>\n<p>La temp\u00e9rature renvoy\u00e9e par le capteur de CO2 SCD30 n&rsquo;\u00e9tant pas satisfaisante (trop \u00e9lev\u00e9e au bout d&rsquo;un certain temps), j&rsquo;ai d\u00e9cid\u00e9 d&rsquo;utiliser un banal capteur de temp\u00e9rature <a href=\"http:\/\/www.datasheetcatalog.com\/datasheets_pdf\/L\/M\/3\/5\/LM35C.shtml\" rel=\"noopener\" target=\"_blank\">LM35CZ<\/a>, fiable et tr\u00e8s peu cher. Le convertisseur analogique \/ num\u00e9rique 10 bits int\u00e9gr\u00e9 \u00e0 la carte Arduino num\u00e9rise le signal analogique sur 1024 niveaux (de 0 \u00e0 1023), le 0 correspondant \u00e0 0 volt et le 1023 \u00e0 5 volts. Le pas entre deux niveaux successifs est donc de 5\/1023 = 0,00489 V = 4,89 mV. Puisque le capteur LM35CZ fonctionne de mani\u00e8re lin\u00e9aire (10 mV par \u00b0C), le pas entre deux niveaux successifs repr\u00e9sente 4,89\/10 = 0,489 \u00b0C. Nous pouvons gagner en r\u00e9solution en amplifiant le signal d&rsquo;origine de fa\u00e7on \u00e0 utiliser toute la plage offerte par la carte Arduino (il faut faire attention \u00e0 ne pas d\u00e9passer les 5 V). Le capteur LM35CZ est pr\u00e9vu pour fonctionner jusqu&rsquo;\u00e0 110 \u00b0C. Tel que pr\u00e9c\u00e9demment, nous atteignons une tension maximale de 110&#215;10 = 1100 mV = 1,1 V. En amplifiant le signal d&rsquo;origine 4,9 fois (voir sch\u00e9ma ci-dessous), nous am\u00e9liorons la r\u00e9solution \u00e0 0,489\/4,9 = 0,10 \u00b0C entre deux niveaux successifs. La tension maximale \u00e0 la sortie du capteur amplifi\u00e9 serait alors de 1,1&#215;4,9 = 5,39 V, une tension sup\u00e9rieure aux 5 V \u00e0 ne pas d\u00e9passer, mais comme il ne fera jamais plus de 102\u00b0, il n&rsquo;y a pas de risques.<\/p>\n<p><a href=\"https:\/\/entropie.org\/3615\/wp-content\/uploads\/2021\/04\/lm35.jpg\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/entropie.org\/3615\/wp-content\/uploads\/2021\/04\/lm35-1024x604.jpg\" alt=\"\" width=\"840\" height=\"495\" class=\"alignnone size-large wp-image-4028\" srcset=\"https:\/\/entropie.org\/3615\/wp-content\/uploads\/2021\/04\/lm35-1024x604.jpg 1024w, https:\/\/entropie.org\/3615\/wp-content\/uploads\/2021\/04\/lm35-300x177.jpg 300w, https:\/\/entropie.org\/3615\/wp-content\/uploads\/2021\/04\/lm35-768x453.jpg 768w, https:\/\/entropie.org\/3615\/wp-content\/uploads\/2021\/04\/lm35.jpg 1200w\" sizes=\"(max-width: 709px) 85vw, (max-width: 909px) 67vw, (max-width: 1362px) 62vw, 840px\" \/><\/a><\/p>\n<p>La carte SD est format\u00e9e en FAT 16 (voir <a href=\"https:\/\/www.arduino.cc\/en\/Reference\/SDCardNotes\" rel=\"noopener\" target=\"_blank\">cette page<\/a> du site Arduino) :<\/p>\n<p><a href=\"https:\/\/entropie.org\/3615\/wp-content\/uploads\/2021\/04\/Carte-SD-pour-Arduino.png\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/entropie.org\/3615\/wp-content\/uploads\/2021\/04\/Carte-SD-pour-Arduino-300x240.png\" alt=\"\" width=\"300\" height=\"240\" class=\"alignnone size-medium wp-image-3998\" srcset=\"https:\/\/entropie.org\/3615\/wp-content\/uploads\/2021\/04\/Carte-SD-pour-Arduino-300x240.png 300w, https:\/\/entropie.org\/3615\/wp-content\/uploads\/2021\/04\/Carte-SD-pour-Arduino.png 551w\" sizes=\"(max-width: 300px) 85vw, 300px\" \/><\/a> <a href=\"https:\/\/entropie.org\/3615\/wp-content\/uploads\/2021\/04\/Carte-SD-pour-Arduino-FAT16.png\"><\/p>\n<p><a href=\"https:\/\/entropie.org\/3615\/wp-content\/uploads\/2021\/04\/Carte-SD-pour-Arduino-FAT16.png\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/entropie.org\/3615\/wp-content\/uploads\/2021\/04\/Carte-SD-pour-Arduino-FAT16-300x153.png\" alt=\"\" width=\"300\" height=\"153\" class=\"alignnone size-medium wp-image-4003\" srcset=\"https:\/\/entropie.org\/3615\/wp-content\/uploads\/2021\/04\/Carte-SD-pour-Arduino-FAT16-300x153.png 300w, https:\/\/entropie.org\/3615\/wp-content\/uploads\/2021\/04\/Carte-SD-pour-Arduino-FAT16.png 327w\" sizes=\"(max-width: 300px) 85vw, 300px\" \/><\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>J&rsquo;ai mis le code source de mon capteur de CO2 (\u00e9galement enregistreur de donn\u00e9es) sur GitHub. Un fichier que j&rsquo;ai \u00e9crit en Python permet de r\u00e9cup\u00e9rer les donn\u00e9es et de tracer automatiquement la courbe du taux de CO2 en appuyant sur un seul bouton (sur GitHub \u00e9galement). La temp\u00e9rature renvoy\u00e9e par le capteur de CO2 &hellip; <a href=\"https:\/\/entropie.org\/3615\/index.php\/2021\/03\/28\/enregistreur-de-donnees-c02-temperature-humidite\/\" class=\"more-link\">Continuer la lecture<span class=\"screen-reader-text\"> de &laquo;&nbsp;Enregistreur de donn\u00e9es avec Arduino Nano :  C02, Temp\u00e9rature, Humidit\u00e9&nbsp;&raquo;<\/span><\/a><\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[10,42],"tags":[],"class_list":["post-3917","post","type-post","status-publish","format-standard","hentry","category-arduino","category-covid-19"],"_links":{"self":[{"href":"https:\/\/entropie.org\/3615\/index.php\/wp-json\/wp\/v2\/posts\/3917"}],"collection":[{"href":"https:\/\/entropie.org\/3615\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/entropie.org\/3615\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/entropie.org\/3615\/index.php\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/entropie.org\/3615\/index.php\/wp-json\/wp\/v2\/comments?post=3917"}],"version-history":[{"count":35,"href":"https:\/\/entropie.org\/3615\/index.php\/wp-json\/wp\/v2\/posts\/3917\/revisions"}],"predecessor-version":[{"id":4043,"href":"https:\/\/entropie.org\/3615\/index.php\/wp-json\/wp\/v2\/posts\/3917\/revisions\/4043"}],"wp:attachment":[{"href":"https:\/\/entropie.org\/3615\/index.php\/wp-json\/wp\/v2\/media?parent=3917"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/entropie.org\/3615\/index.php\/wp-json\/wp\/v2\/categories?post=3917"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/entropie.org\/3615\/index.php\/wp-json\/wp\/v2\/tags?post=3917"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}