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Questions tagged [l2cap]

Bluetooth Logical link control and adaptation protocol resides in the data link layer.

L2CAP is used within the Bluetooth protocol stack. It passes packets to either the Host Controller Interface (HCI) or on a hostless system, directly to the Link Manager/ACL link. L2CAP provides connection-oriented and connectionless data services to upper layer protocols with protocol multiplexing capability, segmentation and reassembly operation, and group abstractions. L2CAP permits higher level protocols and applications to transmit and receive L2CAP data packets up to 64 kilobytes in length.

L2CAP's functions include:

  • Multiplexing data between different higher layer protocols.
  • Segmentation and reassembly of packets.
  • Providing one-way transmission management of multicast data to a group of other Bluetooth devices.
  • Quality of service (QoS) management for higher layer protocols.
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Android BLE Connection time interval

I am developing a BLE application on Nexus 4 using Android BLE API. I have a few questions/doubts: 1) Is there a way to set/override the connection or notification interval of BLE central device. I have found that for Android, the default connection…
CoDe
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Bluetooth protocol (RFCOMM, L2CAP and ACL)

From what I've read from Bluetooth Essentials for Programmers, this books mentions some points that I dont quite understand. RFCOMM is a reliable stream-based protocol. L2CAP is a packet-based protocol that can be configured with varying levels…
Sam
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Bluetooth LE L2CAP CID vs. PSM

I've been teaching myself how to write programs in C for BLE devices using the BlueZ API. However, I seem to be stumped on one particular aspect of the sockaddr_l2 struct. The definition I am using is the following: struct sockaddr_l2 { …
Jeremy Roy
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Trying to bind bluetooth socket to PSM 17 and 19 returns EACCESS on MeeGo

I am trying to use Nokia N9 (meego) as a virtual Bluetooth mouse/keyboard. I am trying to use this small program as a starting point but I am running into problem: when I am running this program I get an error telling me that "Bind error (PSM 19):…
sdkljhdf hda
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Virtual HID-keyboard for OS X

I'm trying to create a virtual bluetooth keyboard client for Mac OS. that means my Mac will serve as a BT KB. I read about the bluetooth API in OS X (in ObjC), and I also found an HID API for Mac (in C) To make this work I understand I need to…
eyalw
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How can I instantiate a L2Cap socket in Android?

I see that a Bluetooth socket can be of type TYPE_L2CAP, but the constructor for BluetoothSocket seems to be private and I can only find a method to instantiate a socket of type RFCOMM. How can I obtain and use a L2CAP socket? Is it actually…
nsndvd
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How Can I Establish A L2Capp Interrupt Channel Connection?

Im trying to open a L2Cap HID Channel And Interrupt channel so I can send HID commands to a bluetooth device. I've done all my service advertising and device paring and established a baseband connection. The Hid Control channel opens fine. When I…
dubbeat
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Bluetooth AVRCP control from Windows

I'm trying to implement an AVRCP/A2DP connection between my Android phone and my car PC. The A2DP bit basically works out of the box so no issue there. I want the PC to be the AVRCP CT (controller) and the A2DP sink. The phone is the AVRCP TG…
ChristianH
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Bluetooth LE - L2CAP CO Channel on android

I'm trying to connect an android device to an embedded control unit via L2CAP CO (Connection Oriented) with Bluetooth LE. Apple created in iOS a new function to create a custom L2CAP Channel…
javaBeCool
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Sending GAP ACL L2CAP Data Packets

To give some background on this question, try to test the CVE-2020-0022. Not sure how to trigger it in the end. Wrote this code that sends fragmented ACL L2CAP Data packets, so maybe somebody finds it useful. Before you should change the ACL MTU to…
dev
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Bluetooth L2CAP server on Windows 10 (c#)

With iOS 11, Apple added support for MFI-free L2CAP protocol. I need to implement L2CAP server on C# (Windows 10) to allow ios client L2CAP connections. Does anyone know a good (or even any) reference (sample code / example) of L2CAP server…
user2156173
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Use BLE L2CAP CoC on Windows

I am trying to use Windows PC as a Central and connect it to BLE L2CAP CoC opened by Android smartphone using BluetoothAdapter#listenUsingL2capChannel(). From what I found after looking through MSDN documentation dedicated to the use of Bluetooth on…
Mirron
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How to create Bluetooth L2CAP connection between two devices?

Android 10 released support for BLE CoC connection so I wanted to try this out by making two simple android 10 apps, which would connect to each other with l2Cap and exchange "Hello World". I wrote two apps, Server app and Client app, both having…
Nikola Maksimovic
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Establishing L2CAP connection over HCI

I have been trying to establish a BLE connection between and send data between two NRF52-52840 USB dongles via sockets. Moreover, I am interested in sending L2CAP data over the HCI layer. I am able to establish a LE connection between the two…
kajax
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Connecting to a bluetooth HID device (mouse) using L2CAP

I'm tring to find a way to connect to a HID bevice (mouse) using L2CAP, this for a android app. but i'm getting error when accepting the connection. I'm using reflection to create the socket. but some thing is wrong with this. can some one please…
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