Dual-mode Bluetooth stack, with small memory footprint.
C Objective-C Makefile Python Java C++ Other
Latest commit b05d5f4 Aug 23, 2016 @mringwal mringwal Merge branch 'develop'


Note: Major API Changes. For older projects, you may use the v0.9 branch. Please see Migration notes

Welcome to BTstack

BTstack is BlueKitchen's implementation of the official Bluetooth stack. It is well suited for small, resource-constraint devices such as 8 or 16 bit embedded systems as it is highly configurable and comes with an ultra small memory footprint. A minimal configuration for an SPP server on a MSP430 can run in 32 kB FLASH and only 4 kB of RAM.

It connects to the Bluetooth modules via a different Bluetooth HCI transport layers (e.g., HCI H4 UART and H5 the "Tree-Wire" protocol, HCI H2 USB). Various platforms can be easily targeted by providing the necessary UART, CPU, and CLOCK implementations.

On smaller embedded systems, a minimal run loop implementation allows to use BTstack without a Real Time OS (RTOS). If a RTOS is already provided, BTstack can be integrated and run as a single thread.

On larger systems, BTstack provides a daemon that connects to a Bluetooth module. Multiple applications can communicate with this daemon over different inter-process communication methods.

BTstack supports both, the Central and the Peripheral Role of Bluetooth 4.2 Low Energy specification. It can be configures as both a single mode or a dual mode stack.

BTstack is free for non-commercial use. For commercial use, tell us a bit about your project to get a quote. It has been qualified with the the Bluetooth SIG for GAP, IOP, HFP, HSP, SPP, PAN profiles and GATT, SM of the Bluetooth 4.2 LE Central and Peripheral roles (QD ID 25340).


Supported Protocols

  • L2CAP
  • SDP
  • BNEP
  • ATT
  • SM

Supported Profiles

  • GAP
  • IOP
  • HFP
  • HSP
  • SPP
  • PAN
  • GATT

Coming next: HID, HOGP, A2DP, and more.

Evaluation Platforms

Embedded Platforms:

Status Platform
buildstatus EZ430-RF256x Bluetooth Evaluation Tool for MSP430
buildstatus MSP430F5438 Experimenter Board for MSP430 with Bluetooth CC2564 Module Evaluation Board
buildstatus MSP-EXP430F5529LP LaunchPad with Bluetooth CC2564 Module Evaluation Board and EM Adapter BoosterPack with additional 32768Hz quartz oscillator
buildstatus STM32 Nucleo development board NUCLEO-F103RB with Bluetooth CC2564 Module Evaluation Board and EM Adapter BoosterPack with additional 32768Hz quartz oscillator
buildstatus Microchip's PIC32 Bluetooth Audio Development Kit
buildstatus RedBear Duo with Broadcom BCM43438 A1

Other Platforms:

Status Platform
buildstatus posix: Unix-based system talking to Bluetooth module via serial port
buildstatus libusb: Unix-based system talking via USB Bluetooth dongle
buildstatus daemon: TCP and Unix domain named socket client-server architecture supporting multiple clients
buildstatus java: Java wrapper for daemon
buildstatus iOS: daemon for iOS jailbreak devices, C client-server API
buildstatus mtk: daemon for rooted Android devices, based on Mediatek MT65xx processor, Java and C client-server API
buildstatus wiced: Broadcom platforms that support the WICED SDK

Supported Chipsets

Chipsets Status
TI CC256x, WL183x H4 incl. eHCIll support and SCO-over-HCI (chipset/cc256x)
CSR 8x10, 8x11 H4 + H5 supported, SCO-over-HCI missing (chipset/csr)
STM STLC2500D working, no support for custom deep sleep management (chipset/stlc2500d)
TC35661 working, BLE patches missing (chipset/tc3566x)
EM 9301 (LE-only) working, used on Arduino Shield (chipset/em9301)
CSR USB Dongles complete, incl. SCO-over-HCI
Broadcom USB Dongles complete, SCO-over-HCI missing
Broadcom BCM43438 complete. UART baudrate limited to 3 mbps, SCO-over-HCI missing

Source Tree Overview

Path Description
chipset Support for individual Bluetooth chipsets
doc Sources for BTstack documentation
example Example applications available for all ports
platform Support for special OSs and/or MCU architectures
port Complete port for a MCU + Chipset combinations
src Bluetooth stack implementation
test Unit and PTS tests
tool Helper tools for BTstack

Discussion and Community Support

BTstack Google Group