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 Kernel 1.6.0

We are pleased to announce the release of Zephyr kernel version 1.6.0. This release introduces the unified Kernel replacing the separate nano- and micro-kernels and simplifying the overall Zephyr architecture and programming interfaces. Support for the ARM Cortex-M0/M0+ family was added and board support for Cortex-M was expanded. Additionally, this release adds many improvements for documentation, build infrastructure, and testing.

Major enhancements included with the release:

Introduced the Unified Kernel; the nano and micro kernel were removed.
The legacy API is still supported but deprecated.
Legacy tests and samples were moved to tests/legacy and samples/legacy.
Unified kernel documentation was added and legacy nanokernel/microkernel documentation was removed.
Added support for several ARM Cortex-M boards
Added support for USB mass storage and access to the filesystem.
Added native Bluetooth Controller support. Currently nRF51 & nRF52 are supported.

A detailed list of changes since v1.5.0 by component follows:

Kernel

Introduced the unified kernel.
Removed deprecated Tasks IRQs.
Removed deprecated dynamic interrupt API.
Added DLIST to operate in all elements of a doubly-linked list.
SLIST: Added sys_slist_get() to fetch and remove the head, also Added append_list and merge_slist.
Added nano_work_pending to check if it is pending execution.
Unified: Added support for k_malloc and k_free.
Renamed kernel objects event to alert and memory map to memory slab.
Changed memory pool, memory maps, message queues and event handling APIs.

Architectures

ARC: Removed CONFIG_TIMER0_CLOCK_FREQ.
ARC: Unified linker scripts.
ARC: Removed dynamic interrupts.
ARM: Added choice to use floating point ABI.
ARM: Added NXP Kinetis kconfig options to configure clocks.
ARM: Removed dynamic interrupts and exceptions.
ARM: Atmel: Added constants and structures for watchdog registers.
ARM: Added support for ARM Cortex-M0/M0+.
x86: Removed dynamic interrupts and exceptions.
x86: Declared internal API for interrupt controllers.
x86: Changed IRQ controller to return -1 if cannot determine source vector.
x86: Grouped Quark SoC’s under intel_quark family.
x86: Optimized and simplified IRQ and exception stubs.

Boards

Renamed board Quark SE devboard to Quark SE C1000 devboard.
Renamed board Quark SE SSS devboard to Quark SE C1000 SS devboard.
Quark SE C1000: Disabled IPM and enabled UART0 on the Sensor Subsystem.
Removed basic_cortex_m3 and basic_minuteia boards.
Arduino 101: Removed backup/restore scripts. To restore original bootloader use flashpack utility instead.
Renamed nRF52 Nitrogen to 96Boards Nitrogen.
Added ARM LTD Beetle SoC and V2M Beetle board.
Added Texas Instruments CC3200 LaunchXL support.
Added support for Nordic Semiconductor nRF51822.
Added support for NXP Hexiwear board.

Drivers and Sensors

SPI: Fixed typos in SPI port numbers.
Pinmux: Removed Quark dev unused file.
I2C: Added KSDK shim driver.
Ethernet: Added KSDK shim driver.
Flash: Added KSDK shim driver
I2C: Changed config parameters to SoC specific.
QMSI: Implemented suspend and resume functions QMSI shim drivers
Added HP206C sensor.
Changed config_info pointers to const.
Added support for SoCWatch driver.
Added FXOS8700 accelerometer / magnetometer sensor driver.

Networking

Minor fixes to uIP networking stack (This will be deprecated in 1.7)

Bluetooth

Added native Bluetooth Controller support. Currently nRF51 & nRF52 are supported.
New location for Controller & Host implementations: subsys/bluetooth/
Added raw HCI API to enable physical HCI transport for a Controller-only build.
Added sample raw HCI apps for USB and UART.
Added cross-transport pairing support for the Security Manager Protocol.
Added RFCOMM support (for Bluetooth Classic)
Added basic persistent storage support (filesystem-backed)
Renamed bt_driver API to bt_hci_driver, in anticipation of Bluetooth radio drivers.

Build Infrastructure

Makefile: Changed outdir into board-specific directory to avoid build collisions.
Makefile: Changed to use HOST_OS environment variable.
Makefile: Added support for third party build systems.
Sanity: Added support to filter using environment variables.
Sanity: Added support for multiple toolchains.
Sanity: Added ISSM and ARM GCC embedded toolchains to the supported toolchains.
Sanity: Added extra arguments to be passed to the build.
Sanity: Removed linker VMA/LMA offset check.
Sysgen: Added –kernel_type argument.
Modified build infrastructure to support unified kernel.
SDK: Zephyr: Added check for minimum required version.
Imported get_maintainer.pl from Linux kernel.

Libraries

libc: Added subset of standard types in inttypes.h.
libc: Added support for ‘z’ length specifier.
libc: Removed stddef.h which is provided by the compiler.
libc: printf: Improved code for printing.
printk: Added support for modifiers.
Added CoAP implementation for Zephyr.
File system: Added API to grow or shrink a file.
File system: Added API to get volume statistics.
File system: Added API to flush cache of an opened file.

HALs

QMSI: Updated to version 1.3.1.
HAL: Imported CC3200 SDK.
Imported Nordic MDK nRF51 files.
Imported Kinetis SDK Ethernet phy driver.
Imported SDK RNGA driver.

Documentation

Drivers: Improved Zephyr Driver model.
Updated device power management API.
Unified Kernel primer.
Moved supported board information to the wiki.zephyrproject.org site.
Revised documentation for Kernel Event logger and Timing.

Test and Samples

Fixed incorrect printk usage.
Removed test for dynamic exceptions.
Added USB sample.
Added tests and samples for CoAP client and server.
Added philosophers unified sample.
Removed printf/printk wrappers.
Added Unified kernel API samples.
Imported TinyCrypt test cases for CTR, ECC DSA and ECC DH algorithm.

Deprecations

Deprecated microkernel and nanokernel APIs.
Removed dynamic IRQs and exceptions.
Removed Tasks IRQs.

JIRA Related Items

ZEP-308 - Build System cleanup and Kernel / Application build separation
ZEP-334 - Unified Kernel
ZEP-766 - USB Mass Storage access to internal filesystem
ZEP-1090 - CPU x86 save/restore using new QMSI bootloader flow
ZEP-1173 - Add support for bonding remove
ZEP-48 - define API for interrupt controllers
ZEP-181 - Persistent storage APIs
ZEP-233 - Support USB mass storage device class
ZEP-237 - Support pre-built host tools
ZEP-240 - printk/printf usage in samples
ZEP-248 - Add a BOARD/SOC porting guide
ZEP-342 - USB DFU
ZEP-451 - Quark SE output by default redirected to IPM
ZEP-521 - ARM - add choice to floating point ABI selection
ZEP-546 - UART interrupts not triggered on ARC
ZEP-584 - warn user if SDK is out of date
ZEP-592 - Sanitycheck support for multiple toolchains
ZEP-605 - SMP over BR/EDR
ZEP-614 - Port TinyCrypt 2.0 test cases to Zephyr
ZEP-622 - Add FS API to truncate/shrink a file
ZEP-627 - Port Trickle support from Contiki into current stack
ZEP-635 - Add FS API to grow a file
ZEP-636 - Add FS API to get volume total and free space
ZEP-640 - Remove dynamic IRQs/exceptions from Zephyr
ZEP-653 - QMSI shim driver: Watchdog: Implement suspend and resume callbacks
ZEP-654 - QMSI shim driver: I2C: Implement suspend and resume callbacks
ZEP-657 - QMSI shim driver: AONPT: Implement suspend and resume callbacks
ZEP-661 - QMSI shim driver: SPI: Implement suspend and resume callbacks
ZEP-688 - unify duplicated sections of arch linker scripts
ZEP-715 - Add K64F clock configurations
ZEP-716 - Add Hexiwear board support
ZEP-717 - Add ksdk I2C shim driver
ZEP-718 - Add ksdk ethernet shim driver
ZEP-721 - Add FXOS8700 accelerometer/magnetometer sensor driver
ZEP-737 - Update host tools from upstream: fixdep.c
ZEP-740 - PWM API: Check if ‘flags’ argument is really required
ZEP-745 - Revisit design of PWM Driver API
ZEP-750 - Arduino 101 board should support one configuration using original bootloader
ZEP-758 - Rename Quark SE Devboard to its official name: Quark SE C1000
ZEP-767 - Add FS API to flush cache of an open file
ZEP-775 - Enable USB CDC by default on Arduino 101 and redirect serial to USB
ZEP-783 - ARM Cortex-M0/M0+ support
ZEP-784 - Add support for Nordic Semiconductor nRF51822 SoC
ZEP-850 - remove obsolete boards basic_minuteia and basic_cortex_m3
ZEP-906 - [unified] Add scheduler time slicing support
ZEP-907 - Test memory pool support (with mailboxes)
ZEP-908 - Add task offload to fiber support
ZEP-909 - Adapt tickless idle + power management for ARM
ZEP-910 - Adapt tickless idle for x86
ZEP-912 - Finish renaming kernel object types
ZEP-916 - Eliminate kernel object API anomalies
ZEP-920 - Investigate malloc/free support
ZEP-921 - Miscellaneous documentation work
ZEP-922 - Revise documentation for Kernel Event Logger
ZEP-923 - Revise documentation for Timing
ZEP-924 - Revise documentation for Interrupts
ZEP-925 - API changes to message queues
ZEP-926 - API changes to memory pools
ZEP-927 - API changes to memory maps
ZEP-928 - API changes to event handling
ZEP-930 - Cut over to unified kernel
ZEP-933 - Unified kernel ARC port
ZEP-934 - NIOS_II port
ZEP-935 - Kernel logger support (validation)
ZEP-954 - Update device PM API to allow setting additional power states
ZEP-957 - Create example sample for new unified kernel API usage
ZEP-959 - sync checkpatch.pl with upstream Linux
ZEP-966 - need support for EM7D SOC on em_starterkit
ZEP-975 - DNS client port to new IP stack
ZEP-981 - Add doxygen documentation to both include/kernel.h and include/legacy.h
ZEP-989 - Cache next ready thread instead of finding out the long way
ZEP-993 - Quark SE (x86): Refactor save/restore execution context feature
ZEP-994 - Quark SE (ARC): Add PMA sample
ZEP-996 - Refactor save/restore feature from i2c_qmsi driver
ZEP-997 - Refactor save/restore feature from spi_qmsi driver
ZEP-998 - Refactor save/restore feature from uart_qmsi driver
ZEP-999 - Refactor save/restore feature from gpio_qmsi driver
ZEP-1000 - Refactor save/restore feature from rtc_qmsi driver
ZEP-1001 - Refactor save/restore feature from wdt_qmsi driver
ZEP-1002 - Refactor save/restore feature from counter_qmsi_aonpt driver
ZEP-1004 - Extend counter_qmsi_aon driver to support save/restore peripheral context
ZEP-1005 - Extend dma_qmsi driver to support save/restore peripheral context
ZEP-1006 - Extend soc_flash_qmsi driver to support save/restore peripheral context
ZEP-1008 - Extend pwm_qmsi driver to support save/restore peripheral context
ZEP-1023 - workq in Kernel primer for unified kernel
ZEP-1030 - Enable QMSI shim drivers of SoC peripherals on the sensor subsystem
ZEP-1043 - Update QMSI to 1.2
ZEP-1045 - Add/Enhance shim layer to wrap SOC specific PM implementations
ZEP-1046 - Implement RAM sharing between bootloader and Zephyr
ZEP-1047 - Adapt to new PM related boot flow changes in QMSI boot loader
ZEP-1106 - Fix all test failures from TCF
ZEP-1107 - Update QMSI to 1.3
ZEP-1109 - Texas Instruments CC3200 LaunchXL Support
ZEP-1119 - move top level usb/ to sys/usb
ZEP-1120 - move top level fs/ to sys/fs
ZEP-1121 - Add config support for enabling SoCWatch in Zephyr
ZEP-1140 - Add a unified kernel version of power_mgr sample app for testing PM code with the new kernel
ZEP-1188 - Add an API to retrieve pending interrupts for wake events
ZEP-1191 - Create wiki page for Hexiwear board
ZEP-1235 - Basic shell support for file system browsing
ZEP-1245 - ARM LTD V2M Beetle Support
ZEP-1313 - porting and user guides must include a security section
ZEP-1386 - Revise power management document to reflect latest changes
ZEP-199 - Zephyr driver model is undocumented
ZEP-436 - Test case tests/kernel/test_mem_safe fails on ARM hardware
ZEP-471 - Ethernet packet with multicast address is not working
ZEP-472 - Ethernet packets are getting missed if sent in quick succession.
ZEP-517 - build on windows failed “zephyr/Makefile:869: *** multiple target patterns”
ZEP-528 - ARC has 2 almost identical copies of the linker script
ZEP-577 - Sample application source does not compile on Windows
ZEP-601 - enable CONFIG_DEBUG_INFO
ZEP-602 - unhandled CPU exceptions/interrupts report wrong faulting vector if triggered by CPU
ZEP-615 - Un-supported flash erase size listed in SPI flash w25qxxdv driver header file
ZEP-639 - device_pm_ops structure should be defined as static
ZEP-686 - docs: Info in “Application Development Primer” and “Developing an Application and the Build System” is largely duplicated
ZEP-698 - samples/task_profiler issues
ZEP-707 - mem_safe test stomps on top of .data and bottom of .noinit
ZEP-724 - build on windows failed: ‘make: execvp: uname: File or path name too long’
ZEP-733 - Minimal libc shouldn’t be providing stddef.h
ZEP-762 - unexpected “abspath” and “notdir” from mingw make system
ZEP-777 - samples/driver/i2c_stts751: kconfig build warning from “select DMA_QMSI”
ZEP-778 - Samples/drivers/i2c_lsm9ds0: kconfig build warning from “select DMA_QMSI”
ZEP-779 - Using current MinGW gcc version 5.3.0 breaks Zephyr build on Windows
ZEP-845 - UART for ARC on Arduino 101 behaves unexpectedly
ZEP-905 - hello_world compilation for arduino_due target fails when using CROSS_COMPILE
ZEP-940 - Fail to get ATT response
ZEP-950 - USB: Device is not listed by USB20CV test suite
ZEP-961 - samples: other cases cannot execute after run aon_counter case
ZEP-967 - Sanity doesn’t build ‘samples/usb/dfu’ with assertions (-R)
ZEP-970 - Sanity doesn’t build ‘tests/kernel/test_build’ with assertions (-R)
ZEP-982 - Minimal libc has EWOULDBLOCK != EAGAIN
ZEP-1014 - [TCF] tests/bluetooth/init build fail
ZEP-1025 - Unified kernel build sometimes breaks on a missing .d dependency file.
ZEP-1027 - Documentation for GCC ARM is not accurate
ZEP-1031 - qmsi: dma: driver test fails with LLVM
ZEP-1048 - grove_lcd sample: sample does not work if you disable serial
ZEP-1051 - mpool allocation failed after defrag twice…
ZEP-1062 - Unified kernel isn’t compatible with CONFIG_NEWLIB_LIBC
ZEP-1074 - ATT retrying misbehaves when ATT insufficient Authentication is received
ZEP-1076 - “samples/philosophers/unified” build failed with dynamic stack
ZEP-1077 - “samples/philosophers/unified” build warnings with NUM_PHIL<6
ZEP-1079 - Licensing not clear for imported components
ZEP-1097 - ENC28J60 driver fails on concurrent tx and rx
ZEP-1098 - ENC28J60 fails to receive big data frames
ZEP-1100 - Current master still identifies itself as 1.5.0
ZEP-1101 - SYS_KERNEL_VER_PATCHLEVEL() and friends artificially limit version numbers to 4 bits
ZEP-1124 - tests/kernel/test_sprintf/microkernel/testcase.ini#test failure on frdm_k64f
ZEP-1130 - region ‘RAM’ overflowed occurs while building test_hmac_prng
ZEP-1138 - Received packets not being passed to upper layer from IP stack when using ENC28J60 driver
ZEP-1139 - Fix build error when power management is built with unified kernel
ZEP-1141 - TinyCrypt SHA256 test fails with system crash using unified kernel type
ZEP-1144 - TinyCrypt AES128 fixed-key with variable-text test fails using unified kernel type
ZEP-1145 - system hang after TinyCrypt HMAC test
ZEP-1146 - zephyrproject.org home page needs technical scrub for 1.6 release
ZEP-1149 - port ztest framework to unified kernel
ZEP-1154 - tests/samples failing with unified kernel
ZEP-1155 - Fix filesystem API namespace
ZEP-1163 - LIB_INCLUDE_DIR is clobbered in Makefile second pass
ZEP-1164 - ztest skip waiting the test case to finish its execution
ZEP-1179 - Build issues when compiling with LLVM from ISSM (icx)
ZEP-1182 - kernel.h doxygen show unexpected “asm” blocks
ZEP-1183 - btshell return “panic: errcode -1” when init bt
ZEP-1195 - Wrong ATT error code passed to the application
ZEP-1199 - [L2CAP] No credits to receive packet
ZEP-1219 - [L2CAP] Data sent exceeds maximum PDU size
ZEP-1221 - Connection Timeout during pairing
ZEP-1226 - cortex M7 port assembler error
ZEP-1227 - ztest native testing not working in unified kernel
ZEP-1232 - Daily build is failing asserts
ZEP-1234 - Removal of fiber* APIs due to unified migration breaks USB mass storage patchset
ZEP-1247 - Test tests/legacy/benchmark/latency_measure is broken for daily sanitycheck
ZEP-1252 - Test test_chan_blen_transfer does not build for quark_d2000_crb
ZEP-1277 - Flash driver (w25qxxdv) erase function is not checking for offset alignment
ZEP-1278 - Incorrect boundary check in flash driver (w25qxxdv) for erase offset
ZEP-1287 - ARC SPI 1 Port is not working
ZEP-1289 - Race condition with k_sem_take
ZEP-1291 - libzephyr.a dependency on phony “gcc” target
ZEP-1293 - ENC28J60 driver doesn’t work on Arduino 101
ZEP-1295 - incorrect doxygen comment in kernel.h:k_work_pending()
ZEP-1297 - test/legacy/kernel/test_mail: failure on ARC platforms
ZEP-1299 - System can’t resume completely with DMA suspend and resume operation
ZEP-1302 - ENC28J60 fails with rx/tx of long frames
ZEP-1303 - Configuration talks about >32 thread prios, but the kernel does not support it
ZEP-1309 - ARM uses the end of memory for its init stack
ZEP-1310 - ARC uses the end of memory for its init stack
ZEP-1312 - ARC: software crashed at k_mbox_get() with async sending a message
ZEP-1319 - Zephyr is unable to compile when CONFIG_RUNTIME_NMI is enabled on ARM platforms
ZEP-1341 - power_states test app passes wrong value as power state to post_ops functions
ZEP-1343 - tests/drivers/pci_enum: failing on QEMU ARM and X86 due to missing commit
ZEP-1345 - cpu context save and restore could corrupt stack
ZEP-1349 - ARC sleep needs to pass interrupt priority threshold when interrupts are enabled
ZEP-1353 - FDRM k64f Console output broken on normal flash mode

Known Issues

ZEP-1405 - function l2cap_br_conn_req in /subsys/bluetooth/host/l2cap_br.c references uninitialized pointer