Bluetooth Low Energy: un guide complet du débutant

Créer un service personnalisé et plus encore un client Bluetooth Low Energy est une promenade les yeux bandés sur le râteau. Au moins, c'était le cas pour moi il y a 4 ans, lorsque je viens de commencer à travailler avec des appareils BLE. Maintenant, presque tous mes projets impliquent l'utilisation de ce protocole, donc à un moment donné, j'ai dû le comprendre pendant longtemps et douloureusement. 





Le livre de Mohammad Afane "Intro to Bluetooth Low Energy" et une série d'articles sur Novel Bits ont contribué à tout mettre sur les tablettes . Pour moi personnellement, ce livre a été une vraie découverte. Au départ, je l'ai traduit en russe pour mes collègues qui n'ont aucune expérience avec BLE. Avec le consentement de l'auteur (merci beaucoup à lui), j'ai décidé de publier mon travail ici. J'espère que la traduction vous sera utile.





Il s'agit de la première partie de la traduction (il y en aura 5 au total), qui raconte ce qu'est BLE, ses capacités et ses différences par rapport à Bluetooth Classic, et décrit également l'architecture du protocole.





A propos de l'auteur

2006 . , Allegion (Schlage locks), Motorola, Technicolor, Audiovox, Denon & Marantz Group. , : , , ..





2015 , Novel Bits, LLC, web-, , Bluetooth Low Energy.





: mohammad@novelbits.io LinkedIn.





Bluetooth Low Energy

1. Bluetooth Low Energy?

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  • Bluetooth Low Energy (BLE), .. Bluetooth , Bluetooth 4.0. , ( ) , (, , ).





, . Bluetooth Classic , BLE. , , , ( Dual mode Bluetooth devices), .





Figure 1: Types d'appareils Bluetooth
.1: Bluetooth-

BLE:





  • Bluetooth Bluetooth (Classic BLE), , BLE;





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.2: BLE

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Bluetooth Classic BLE

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4.3 BLE

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Figure 3: Architecture BLE
.3: BLE

, . – GAP (Generic Access Profile), GATT (Generic Attribute Profile) Security Manager – .





/ (GAP) (GATT) – , , , .





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-

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  • (GAP, Generic Access Profile);





  • (GATT, Generic Attribute Profile);





  • (ATT, Attribute Protocol);





  • (SM, Security Manager);





  • (L2CAP, Logical Link Control and Adaptation Protocol);





  • - (HCI, Host Controller Interface), .





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  • (PHY, Physical Layer);





  • (Link Layer);





  • (DTM, Direct Test Mode);





  • - (HCI, Host Controller Interface), .





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Figure 4: Spectre de fréquences et canaux radio dans BLE
.4: BLE

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Figure 6: Exemples de packages d'interface de contrôleur d'hôte
.6: -

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(L2CAP)

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BLE L2CAP : (ATT, , GATT) (SMP, , ).





(), (GATT), (SM) (GAP) .






Ceci conclut le premier chapitre du livre. Un grand merci à ceux qui l'ont lu. La partie suivante se concentrera sur les classes d'appareils et la publicité, la méthode par laquelle les appareils communiquent leur présence au monde qui les entoure.








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