This is the documentation for the latest (main) development branch of Zephyr. If you are looking for the documentation of previous releases, use the drop-down menu on the left and select the desired version.

Zephyr 3.4.0 (Working Draft)

We are pleased to announce the release of Zephyr version 3.4.0.

Major enhancements with this release include:

The following sections provide detailed lists of changes by component.

API Changes

Changes in this release

Removed APIs in this release

Deprecated in this release

  • Configuring applications with prj_<board>.conf files has been deprecated, this should be replaced by using a prj.conf with the common configuration and board-specific configuration in board Kconfig fragments in the boards folder of the application.

Stable API changes in this release

New APIs in this release

Kernel

Architectures

  • ARM

  • ARM

  • ARM64

  • RISC-V

  • Xtensa

Bluetooth

  • Audio

  • Direction Finding

  • Host

  • Mesh

    • Added experimental support for Mesh Protocol d1.1r18 specification.

    • Added experimental support for Mesh Binary Large Object Transfer Model d1.0r04_PRr00 specification.

    • Added experimental support for Mesh Device Firmware Update Model d1.0r04_PRr00 specification.

  • Controller

  • HCI Driver

Boards & SoC Support

  • Added support for these SoC series:

  • Removed support for these SoC series:

  • Made these changes in other SoC series:

  • Added support for these ARC boards:

  • Added support for these ARM boards:

    • Seeed Studio Wio Terminal

  • Added support for these ARM64 boards:

  • Added support for these RISC-V boards:

  • Added support for these X86 boards:

  • Added support for these Xtensa boards:

  • Made these changes for ARC boards:

  • Made these changes for ARM boards:

  • Made these changes for ARM64 boards:

  • Made these changes for RISC-V boards:

  • Made these changes for X86 boards:

  • Made these changes for Xtensa boards:

  • Removed support for these ARC boards:

  • Removed support for these ARM boards:

  • Removed support for these ARM64 boards:

  • Removed support for these RISC-V boards:

    • BeagleV Starlight JH7100

  • Removed support for these X86 boards:

  • Removed support for these Xtensa boards:

  • Made these changes in other boards:

  • Added support for these following shields:

Build system and infrastructure

  • Fixed an issue whereby older versions of the Zephyr SDK toolchain were used instead of the latest compatible version.

  • Fixed an issue whereby building an application with sysbuild and specifying mcuboot’s verification to be checksum only did not build a bootable image.

  • Fixed an issue whereby if no prj.conf file was present then board configuration files would not be included by emitting a fatal error. As a result, prj.conf files are now mandatory in projects.

  • Introduced support for extending/replacing the signing mechanism in zephyr, see West extending signing for further details.

Drivers and Sensors

  • ADC

  • MCUX LPADC driver now uses the channel parameter to select a software channel configuration buffer. Use zephyr,input-positive and zephyr,input-negative devicetree properties to select the hardware channel(s) to link a software channel configuration to.

  • Battery-backed RAM

    • Added MCP7940N battery-backed RTC SRAM driver.

  • CAN

  • Clock control

  • Counter

  • Crypto

  • DAC

  • DFU

  • Disk

  • Display

  • DMA

  • EEPROM

  • Entropy

  • ESPI

  • Ethernet

  • Flash

    • Introduced new flash API call flash_ex_op() which calls ec_op() callback provided by a flash driver. This allows to perform extra operations on flash devices, defined by Zephyr Flash API or by vendor specific header files. CONFIG_FLASH_HAS_EX_OP should be selected by the driver to indicate that extra operations are supported. To enable extra operations user should select CONFIG_FLASH_EX_OP_ENABLED.

  • FPGA

  • Fuel Gauge

  • GPIO

  • hwinfo

  • I2C

  • I2S

  • I3C

  • IEEE 802.15.4

  • Interrupt Controller

  • IPM

  • KSCAN

  • LED

  • MBOX

  • MEMC

  • PCIE

  • PECI

  • Retained memory

    • Retained memory (retained_mem) driver has been added with backends for Nordic nRF GPREGRET, and uninitialised RAM.

Trusted Firmware-M

  • Pin control

  • PWM

  • Power domain

  • Regulators

  • Reset

  • SDHC

  • Sensor

  • Serial

  • SPI

  • Timer

  • USB

  • W1

  • Watchdog

  • WiFi

Networking

  • Wi-Fi

    • TWT intervals are changed from milli-seconds to micro-seconds, interval variables are also renamed.

USB

Devicetree

Libraries / Subsystems

HALs

MCUboot

Storage

Trusted Firmware-M

zcbor

Documentation

Tests and Samples