release-notes.txt

RIOT-2018.04 - Release Notes
============================
RIOT is a multi-threading operating system which enables soft real-time
capabilities and comes with support for a range of devices that are typically
found in the Internet of Things: 8-bit and 16-bit microcontrollers as well as
light-weight 32-bit processors.

RIOT is based on the following design principles: energy-efficiency, soft
real-time capabilities, small memory footprint, modularity, and uniform API
access, independent of the underlying hardware (with partial POSIX compliance).

RIOT is developed by an international open-source community which is
independent of specific vendors (e.g. similarly to the Linux community) and is
licensed with a non-viral copyleft license (LGPLv2.1), which allows indirect
business models around the free open-source software platform provided by RIOT.


About this release:
===================
The 2018.04 release includes major progress in support for current crypto
libraries.  A lot of work has gone into updating drivers to RIOT's unified
configuration scheme.  Support for ten new boards has been added.  In our quest
to improve and automate testing, many test scripts have been fixed and
improved, and RIOT's CI now runs many tests on real hardware during its nightly
build testing. And as usual, many tiny fixes and improvements have been merged.

About 390 pull requests with about 1073 commits have been merged since the last
release and about 54 issues have been solved. 44 people contributed with code
in 98 days. Approximately 1491 files have been touched with 208426 insertions.


Notations used below:
=====================
    + means new feature/item
    * means modified feature/item
    - means removed feature/item

New features and changes
========================
System libraries
----------------
    - cbor: deprecated in favour of cn-cbor
    + hashes: add sha-3 implementation

Networking
----------
    * netdev: replaced "struct iovec" with iolist_t
    + nanocoap: added server-side block1 support
    + skald: a BLE advertising stack

Packages
--------
    + cayenne-lpp: A Cayenne LPP library written in C
    + HACL*: a formally verified cryptographic library written in F*
    + qDSA: Small and Secure Digital Signatures with Curve-based
            Diffie--Hellman Key Pairs
    + libcose: Constrained node COSE library
    + cn-cbor: A constrained node implementation of CBOR in C
    + ucglib

Boards
------
    + arduino-mkrfox1200
    + frdm-kw41z
    + jiminy-mega256rfr2
    + mega-xplained
    + nucleo-l433rc
    + nucleo-l452re
    + slstk3401a
    + slwstk6000b
    + stk3600
    + stk3700

CPU
---
    + atmega1284p
    + NXP Kinetis KW41Z

Device Drivers
--------------
    + bmx055: Bosch bmx055 9-axis IMU
    + ata8520e: Microchip ATA8520E Sigfox(tm) transceiver

Build System / Tooling
----------------------
    + ci: initial on-hardware test support

Known Issues
===========

Please refer to the issue tracker at https://github.com/RIOT-OS/RIOT/issues.

Acknowledgements
================
We would like to thank all companies (vendors) that provided us with (their)
hardware for porting and testing RIOT-OS. Further thanks go to companies and
institutions that directly sponsored development time. And finally, big thanks
to all of you contributing in so many different ways to make RIOT worthwhile!

More information
================
http://www.riot-os.org

Mailing lists
-------------
* RIOT OS kernel developers list
  devel@riot-os.org (http://lists.riot-os.org/mailman/listinfo/devel)
* RIOT OS users list
  users@riot-os.org (http://lists.riot-os.org/mailman/listinfo/users)
* RIOT commits
  commits@riot-os.org (http://lists.riot-os.org/mailman/listinfo/commits)
* Github notifications
  notifications@riot-os.org (http://lists.riot-os.org/mailman/listinfo/notifications)

IRC
---
* Join the RIOT IRC channel at: irc.freenode.net, #riot-os

License
=======
* The code developed by the RIOT community is licensed under the GNU Lesser
  General Public License (LGPL) version 2.1 as published by the Free Software
  Foundation.
* Some external sources and packages are published under a separate license.

All code files contain licensing information.



RIOT-2018.01 - Release Notes
============================
RIOT is a multi-threading operating system which enables soft real-time
capabilities and comes with support for a range of devices that are typically
found in the Internet of Things: 8-bit and 16-bit microcontrollers as well as
light-weight 32-bit processors.

RIOT is based on the following design principles: energy-efficiency, soft
real-time capabilities, small memory footprint, modularity, and uniform API
access, independent of the underlying hardware (with partial POSIX compliance).

RIOT is developed by an international open-source community which is
independent of specific vendors (e.g. similarly to the Linux community) and is
licensed with a non-viral copyleft license (LGPLv2.1), which allows indirect
business models around the free open-source software platform provided by RIOT.


About this release:
===================
The 2018.01 release includes major progress in RIOTs network communication
capabilities, i.e., rewrite of GNRC's neighbour discovery, confirmable messages
in (g)CoAP, LoRa, and GoMacH as well as updates on CCN-lite and LWIP.
Furthermore, RIOT contributes to _IKEA-Hacking_ by bringing support for
the smart home lighting system TRADFRI (note: this will void the warranty).
Needless to say that this release also adds and updates support for several
platforms, drivers, and of course lots of enhancements to the documentation
as well as numerous bug fixes. Last but not least, RIOT now has an official
code of conduct (https://github.com/RIOT-OS/RIOT/blob/master/CODE_OF_CONDUCT.md)

More than 442 pull requests with about 865 commits have been merged since the
last release and about 96 issues have been solved. 54 people contributed with code
in 96 days. Approximately 2370 files have been touched with 223970 insertions
and 181409 deletions.


Notations used below:
=====================
    + means new feature/item
    * means modified feature/item
    - means removed feature/item


New features and changes
========================
System libraries
----------------
    + event: event queue framework like libevent

Networking
----------
    + gcoap: confirmable messages
    + nanocoap: no external package anymore
    * GNRC: major rewrite of neighbour discovery
    * GNRC: new API for network interface handling

Packages
--------
    + gecko_sdk: library for EFM/EFR/EZR32 MCUs
    * libcoap: git patching fixed
    + littlefs: filesystem for constraint devices
    - nanocoap: now part of RIOT
    * openthread: updated
    + semtech-loramac: LoRa MAC
    + umorse: morse encoder

Boards
------
    + acd52832
    * common: restructured shared code for boards
    + b-l475e-iot01a
    + bluepill
    + ikea-tradfri
    - pca10000
    - pca10005
    - qemu-i386
    + ruuvitag
    + sltb001a
    + teensy31
    + thingy52
    - x86

CPU
---
    + efm32
    * kinetis: unified all MCU variants
    - x86

Device Drivers
--------------
    + socket_zep: emulated IEEE 802.15.4 device over a UDP for native
    + hts221
    + lc709203f
    + lis2dh12
    + rn2xx3
    + soft_spi
    + tja1042

Build System / Tooling
----------------------
    + flake8: python code checker
    * make: set `-Wall -Wextra` as default for all compilers and platforms
    - sniffer: moved to applications repository
    + tests: add automated test scripts for many apps


Fixed Issues from the last release (2017.10)
============================================
#2143: unittests: tests-core doesn't compile for all platforms
#4499: handle of l2src_len in gnrc_ndp_rtr_sol_handle
#4822: kw2xrf: packet loss when packets get fragmented
#5005: ndp: router advertisement sent with global address
#5122: NDP: global unicast address on non-6LBR nodes disappears after a while
#5656: Possible Weakness with locking in the GNRC network stack
#5790: ND: Lost of Global IPV6 on node after sending lot of UDP frame from BR
#5944: msp430: ipv6_hdr unittests fail
#6451: Wrong value in SRF08 driver
#6502: cpu/stm32l1: RTC broken


Known Issues
============
Networking related issues
-------------------------
#5230: gnrc ipv6: multicast packets are not dispatched to the upper layers
#5858: gnrc: 6lo: potential problem with reassembly of fragments: If one frame
       gets lost the reassembly state machine might get out of sync
#7035: lwIP: hangs due to sema change after a while

Timer related issues
--------------------
#5103: xtimer: weird behavior of tests/xtimer_drift: xtimer_drift randomly
       jumps a few seconds on nrf52
#5338: xtimer: xtimer_now() not ISR safe for non-32-bit platforms.
#6052: tests: xtimer_drift gets stuck: application freezes after ~30-200 seconds
#7114: xtimer: add's items to the wrong list if the timer overflows between
       _xtimer_now() and irq_disable()

native related issues
---------------------
#495:  native not float safe: When FPU is used and an asynchronous context
       switch occurs, either the stack gets corrupted or a floating point
       exception occurs.
#6442: cpu/native: timer interrupt does not yield thread

other platform related issues
-----------------------------
#1891: newlib-nano: Printf formatting does not work properly for some numeric
       types: PRI[uxdi]64, PRI[uxdi]8 and float are not parsed in newlib-nano
#4866: not all GPIO driver implementations are thread safe: Due to non-atomic
       operations in the drivers some pin configurations might get lost.
#5848: Arduino: Race condition in sys/arduino/Makefile.include
#6018: nRF52 gnrc 6lowpan ble memory leak
#6261: SAMD21: TC3 & TC4 issue when using TCC2
#6379: nrf52dk/nordic_soft_device: not working anymore
#6437: periph/spi: Leftovers from SPI rework
#6526: atmega based boards freeze when main thread is over
#6836: Issuing a reboot on ATmega328p makes the board loop-reboot
#7753: pic32-wifire: race-condition when linking in concurrent build

other issues
------------
#1263: TLSF implementation contains (a) read-before-write error(s).
#3366: periph/i2c: handle NACK
#4488: Making the newlib thread-safe: When calling puts/printf after
       thread_create(), the CPU hangs for DMA enabled UART drivers.
#5776: make: Predefining CFLAGS are parsed weirdly
#5863: OSX + SAMR21-xpro: shell cannot handle inputs of length >64 chars
#5962: Makefile: UNDEF variable is not working as documented


Acknowledgements
================
We would like to thank all companies (vendors) that provided us with (their)
hardware for porting and testing RIOT-OS. Further thanks go to companies and
institutions that directly sponsored development time. And finally, big thanks
to all of you contributing in so many different ways to make RIOT worthwhile!

More information
================
http://www.riot-os.org

Mailing lists
-------------
* RIOT OS kernel developers list
  devel@riot-os.org (http://lists.riot-os.org/mailman/listinfo/devel)
* RIOT OS users list
  users@riot-os.org (http://lists.riot-os.org/mailman/listinfo/users)
* RIOT commits
  commits@riot-os.org (http://lists.riot-os.org/mailman/listinfo/commits)
* Github notifications
  notifications@riot-os.org (http://lists.riot-os.org/mailman/listinfo/notifications)

IRC
---
* Join the RIOT IRC channel at: irc.freenode.net, #riot-os

License
=======
* The code developed by the RIOT community is licensed under the GNU Lesser
  General Public License (LGPL) version 2.1 as published by the Free Software
  Foundation.
* Some external sources and packages are published under a separate license.

All code files contain licensing information.



RIOT-2017.10 - Release Notes
============================
RIOT is a multi-threading operating system which enables soft real-time
capabilities and comes with support for a range of devices that are typically
found in the Internet of Things: 8-bit microcontrollers, 16-bit
microcontrollers and light-weight 32-bit processors.

RIOT is based on the following design principles: energy-efficiency, soft
real-time capabilities, small memory footprint, modularity, and uniform API
access, independent of the underlying hardware (with partial POSIX compliance).

RIOT is developed by an international open-source community which is
independent of specific vendors (e.g. similarly to the Linux community) and is
licensed with a non-viral copyleft license (LGPLv2.1), which allows indirect
business models around the free open-source software platform provided by RIOT.

About this release:
===================
Most notable, this release is bringing RIOT a step closer to supporting
over-the-air-updates by containing initial support for MCUBoot.
Furthermore, it adds support for some new platforms (e.g. arduino-mkzero,
nucleos, and frdm-k22f), drivers (e.g. my9221, apa102, ds1307), and of course
a large number of bug fixes (e.g. `make buildtest` now working properly,
various fixes to `xtimer`).

About 390 pull requests with about 500 commits have been merged since the last
release and about 60 issues have been solved. 39 people contributed with code
in 113 days. 1825 files have been touched with 223454 insertions and 66146 deletions.

Notations used below:
=====================
+ means new feature/item
* means modified feature/item
- means removed feature/item

New features and changes
========================

Bootloader
-----------
+ MCUBoot: A secure bootloader for ARM MCUs is now supported. This initial support
includes only the nrf52dk board. For more information about it refer to the mcuboot github
page at https://github.com/runtimeco/mcuboot/blob/master/README-RIOT.rst

System libraries
----------------
+ bcd: binary coded decimal en/decoder

Networking
----------
+ gcoap: Add URI-query strings for requests + various fixes

Packages
--------
* lwip: Updated to v2.0.3

Boards
------
+ NXP frdm-k22f
+ STM nucleo144-f722
+ Arduino arduino-mkzero
+ ti CC2650 LaunchPad
- weio

CPU
---
+ NXP k22f
+ cc2538: ADC
+ stm32l4: RTC
+ samr21e18a
+ msp430: added flashpage driver
- lpc11u34
* stm32: unified stmclk implementations, reworked RTC
* sam0: heavy unification and refactoring, updated vendor headers
+ sam_common: started unification of sam0 and sam3
* cortexm: interrupt vector cleanup

Device Drivers
--------------
+ my9221 - LED controller + Seeed Studio Grove LED bar
+ apa102 - RGB LED
+ ds1307: RTC
+ SAUL support: lps331ap
* SAUL gpio: allow configuration of initial state and low-active signals
* sdcard_spi: added mtd interface
* PM: fixed selection of default implementations for `pm_off` and `pm_set_lowest`

Build System / Tooling
------------
+ make: added pkt-prepare target
* gcc: enabled `-fdiagnostics-color` per default for `arm` and `native` targets
* edbg: use as default flash tool for sam0-based boards
+ added LOSTANDFOUND.md for listing removed features

Fixed Issues from the last 3 releases (known issues missing in 2017.04 and 2017.07)
===================================================================================
#2006: cpu/nrf51822: timer callback may be fired too early
#4841: xtimer: timer already in the list:
#4590: pkg: building relic with clang fails.
#4694: drivers/lm75a: does not build
#4902: xtimer: xtimer_set: xtimer_set does not handle integer overflows well
#5128: make: buildtest breaks when exporting FEATURES_PROVIDED var
#5207: make: buildest fails with board dependent application Makefiles
#5361: cpu/cc26x0: timer broken
#5460: cpu/samd21: i2c timing with compiler optimization
#5489: cpu/lpc11u34: ADC broken
#5799: kw2x: 15.4 duplicate transmits
#5928: xtimer: usage in board_init() crashes: some boards use the xtimer in there board_init()
       function. The xtimer is however first initialized in the auto_init module which is executed
       after board_init()
#6022: pkg: build order issue
#6331: RTC alarm triggered with 1s delay
#6419: cpu/cc2538: timer broken
#6427: xtimer: infinite loop with xtimer_mutex_lock_timeout
#6501: boards/nucleo: Pin usage collision (SPI clk vs. LED0)
#6542: boards/nucle-f0xx: misconfigured timer configuration
#6904: cpu/saml21: cannot use several EXTI

Known Issues
============
Networking related issues
-------------------------
#3075: nhdp: unnecessary microsecond precision: NHDP works with timer values of microsecond precision
       which is not required. Changing to lower precision would save some memory.
#4048: gnrc: potential racey memory leak
#5016: gnrc_rpl: Rejoining RPL instance as root after reboot messes up routing
#5230: gnrc ipv6: multicast packets are not dispatched to the upper layers
#5656: Possible Weakness with locking in the GNRC network stack: For some operations mutexes to the
       network interfaces need to get unlocked in the current implementation to not get deadlocked.
       Recursive mutexes as provided in #5731 might help to solve this problem.
#5748: gnrc: nodes crashing with too small packet buffer: A packet buffer of size ~512 B might lead
       to crashes. The issue describes this for several hundret nodes, but agressive flooding with
       just two nodes was also shown to lead to this problem.
#5858: gnrc: 6lo: potential problem with reassembly of fragments: If one frame gets lost the reassembly
       state machine might get out of sync
#6123: gnrc: crash with (excessive) traffic
#7035: lwIP: hangs due to sema change after a while
#7737: pkg: libcoap is partially broken and outdated

NDP is not working properly
---------------------------
#4499: handle of l2src_len in gnrc_ndp_rtr_sol_handle: Reception of a router solicitation might lead
       to invalid zero-length link-layer addresses in neighbor cache.
#5005: ndp: router advertisement sent with global address: Under some  circumstances a router might
       send RAs with GUAs. While they are ignored on receive (as RFC-4861 specifies), RAs should have
       link-local addresses and not even be send out this way.
#5122: NDP: global unicast address on non-6LBR nodes disappears after a while: Several issues
       (also see #5760) lead to a global unicast address effectively being banned from the network
       (disappears from neighbor cache, is not added again)
#5467: ipv6 address vanishes when ARO (wrongly) indicates DUP caused by outdated ncache at router
#5539: Border Router: packet not forwarded from ethos to interface 6
#5790: ND: Lost of Global IPV6 on node after sending lot of UDP frame from BR

Timer related issues
--------------------
#5338: xtimer: xtimer_now() not ISR safe for non-32-bit platforms.
#6052: tests: xtimer_drift gets stuck: xtimer_drift application freezes after ~30-200 seconds
#6502: cpu/stm32l1: RTC broken
#7114: xtimer: add's items to the wrong list if the timer overflows between _xtimer_now() and irq_disable()

native related issues
---------------------
#495:  native not float safe: When the FPU is used when an asynchronous context switch occurs, either
       the stack gets corrupted or a floating point exception occurs.
#2175: ubjson: valgind registers "Invalid write of size 4" in unittests
#5796: native: tlsf: early malloc will lead to a crash: TLSF needs pools to be initialized (which is
       currently expected to be done in an application). If a malloc is needed before an application's
       main started (e.g. driver initialization) the node can crash, since no pool is allocated yet.
#6145: native: system reboots on SIGTRAP
#6442: cpu/native: timer interrupt does not yield thread
#7206: native: race-condition in IPC

other platform related issues
-----------------------------
#1891: newlib-nano: Printf formatting does not work properly for some numeric types: PRI[uxdi]64,
       PRI[uxdi]8 and float are not parsed in newlib-nano
#2143: unittests: tests-core doesn't compile for all platforms: GCC build-ins were used in the
       unittests which are not available with msp430-gcc
#2300: qemu unittest fails because of a page fault
#4512: pkg: tests: RELIC unittests fail on iotlab-m3
#4560: make: clang is more pedantic than gcc oonf_api is not building with clang (partly fixed by #4593)
#4822: kw2xrf: packet loss when packets get fragmented
#4876: at86rf2xx: Simultaneous use of different transceiver types is not supported
#4954: chronos: compiling with -O0 breaks
#4866: not all GPIO driver implementations are thread safe: Due to non-atomic operations in the drivers
       some pin configurations might get lost.
#5009: RIOT is saw-toothing in energy consumption (even when idling)
#5103: xtimer: weird behavior of tests/xtimer_drift: xtimer_drift randomly jumps a few seconds on nrf52
#5405: Eratic timings on iotlab-m3 with compression context activated
#5486: at86rf2xx: lost interrupts
#5678: at86rf2xx: failed assertion in _isr
#5944: msp430: ipv6_hdr unittests fail
#5848: arduino: Race condition in sys/arduino/Makefile.include
#6018: nRF52 gnrc 6lowpan ble memory leak
#6261: SAMD21 TC3 & TC4 issue when using TCC2
#6379: nrf52dk/nordic_soft_device: not working anymore
#6437: periph/spi: Leftovers from SPI rework
#6526: atmega based boards freeze when main thread is over
#6836: Issuing a reboot on ATmega328p makes the board loop-reboot
#7347: xtimer_usleep stuck for small values on nucleo-l1
#7753: pic32-wifire: race-condition when linking in concurrent build
#7846: stm32f1: I2C read functions return bogus values with unconnected devices

other issues
------------
#1263: TLSF implementation contains (a) read-before-write error(s).
#3256: make: Setting constants on compile time doesn't really set them everywhere
#3366: periph/i2c: handle NACK
#4488: Making the newlib thread-safe: When calling puts/printf after thread_create(), the CPU hangs
       for DMA enabled uart drivers.
#5561: C++11 extensions in header files
#5776: make: Predefining CFLAGS are parsed weirdly
#5863: OSX +  SAMR21-xpro: shell cannot handle command inputs larger than 64 chars
#5962: Makefile: UNDEF variable is not working as documented
#6451: Wrong value in SRF08 driver
#7800: CBOR is broken

Special Thanks
==============
We would like to give our special thanks to all the companies that provided us
with their hardware for porting and testing, namely the people from (in alphabeticalorder):
Atmel, Freescale, Imagination Technologies, Nordic, OpenMote, Phytec, SiLabs, UDOO,
and Zolertia;
and also companies that directly sponsored development time:
Cisco Systems, Eïsox, Eistec, Ell-i, Engineering Spirit, Mesotic, Nordic, OTA keys and Phytec.
We also would like to thank people from Inria Chile for their work on
OpenThread integration and Semtech LoRa drivers.

More information
================
http://www.riot-os.org

Mailing lists
-------------
* RIOT OS kernel developers list
  devel@riot-os.org (http://lists.riot-os.org/mailman/listinfo/devel)
* RIOT OS users list
  users@riot-os.org (http://lists.riot-os.org/mailman/listinfo/users)
* RIOT commits
  commits@riot-os.org (http://lists.riot-os.org/mailman/listinfo/commits)
* Github notifications
  notifications@riot-os.org (http://lists.riot-os.org/mailman/listinfo/notifications)

IRC
---
* Join the RIOT IRC channel at: irc.freenode.net, #riot-os

License
=======
* The code developed by the RIOT community is licensed under the GNU Lesser General Public
  License (LGPL) version 2.1 as published by the Free Software Foundation.
* Some external sources and pkg are published under a separate license.

All code files contain licensing information.



RIOT-2017.07 - Release Notes
============================
RIOT is a multi-threading operating system which enables soft real-time
capabilities and comes with support for a range of devices that are typically
found in the Internet of Things: 8-bit microcontrollers, 16-bit
microcontrollers and light-weight 32-bit processors.

RIOT is based on the following design principles: energy-efficiency, soft
real-time capabilities, small memory footprint, modularity, and uniform API
access, independent of the underlying hardware (with partial POSIX compliance).

RIOT is developed by an international open-source community which is
independent of specific vendors (e.g. similarly to the Linux community) and is
licensed with a non-viral copyleft license (LGPLv2.1), which allows indirect
business models around the free open-source software platform provided by RIOT.

About this release:
===================
This release provides fixes, code cleanup and improved documentation, as well as
enhancements.
New features brought by this release include:
* CAN support (Controller Area Network)
* Support for CoAP OBSERVE requests
* Basic Thread stack support (initial support for OpenThread)
* radio duty cycling with LwMAC protocol
* LoRa radio drivers supporting Semtech hardware


About 230 pull requests with about 442 commits have been merged since the last
release and about 13 issues have been solved. 45 people contributed with code
in 56 days. 1395 files have been touched with 211720 insertions and 65729 deletions.

Notations used below:
=====================
+ means new feature/item
* means modified feature/item
- means removed feature/item

New features and changes
========================


API changes
-----------
- removed conn API

System libraries
----------------
+ AES CMAC encryption
+ GCC's Stack Smashing Protector (SSP) support
- Remove 3-DES crypto


Networking
----------
+ CAN stack
+ CoAP OBSERVE request
+ LwMAC protocol
+ OpenThread
+ Layer 2 filtering (l2filter)
* LwIP port to v2.0.2
* NHDP port to sock API
- removed conn API


Packages
--------
+ OpenThread

Boards
------
+ Arduino MKR1000 (without WiFi)
+ Nucleo144-f412
+ Nucleo144-f746
+ Nucleo144-f767
+ NZ32-SC151 (STM32L1)
+ ST B-L072-LRWAN1 (with LoRa radio)
+ STM32F769 discovery
* Full support for PhyNode

CPU
---
+ lm4120: SPI support
+ SAM3: ADC support, DAC support
+ SAMD21: flashpage, ADC support
+ SAML21: ADC, I2C support
+ STM32F413vg support
+ STM32F7 family (ARM Cortex-M7)
+ STM32L0 family: I2C support
* STM32: unified DAC support
* STM32F1/F2/F4 clock initialization refactoring


Device Drivers
--------------
+ ADCXX1C I2C ADC support
+ BMP280 temperature/pressure sensor
+ DSP0401 4 digits 16 segment alphanumeric display
+ MMA8x5x motion detection sensor
+ Semtech SX1272 and SX1276 LoRa drivers


Build System
------------
+ EDBG support
+ http download with caching (dlcache)
+ Use Coccinelle static code checker in CI


Special Thanks
==============
We would like to give our special thanks to all the companies that provided us
with their hardware for porting and testing, namely the people from (in alphabeticalorder):
Atmel, Freescale, Imagination Technologies, Nordic, OpenMote, Phytec, SiLabs, UDOO,
and Zolertia;
and also companies that directly sponsored development time:
Cisco Systems, Eïsox, Eistec, Ell-i, Engineering Spirit, Mesotic, Nordic, OTA keys and Phytec.
We also would like to thank people from Inria Chile for their work on
OpenThread integration and Semtech LoRa drivers.

More information
================
http://www.riot-os.org

Mailing lists
-------------
* RIOT OS kernel developers list
  devel@riot-os.org (http://lists.riot-os.org/mailman/listinfo/devel)
* RIOT OS users list
  users@riot-os.org (http://lists.riot-os.org/mailman/listinfo/users)
* RIOT commits
  commits@riot-os.org (http://lists.riot-os.org/mailman/listinfo/commits)
* Github notifications
  notifications@riot-os.org (http://lists.riot-os.org/mailman/listinfo/notifications)

IRC
---
* Join the RIOT IRC channel at: irc.freenode.net, #riot-os

License
=======
* The code developed by the RIOT community is licensed under the GNU Lesser General Public
  License (LGPL) version 2.1 as published by the Free Software Foundation.
* Some external sources and pkg are published under a separate license.

All code files contain licensing information.





RIOT-2017.04 - Release Notes
============================
RIOT is a multi-threading operating system which enables soft real-time
capabilities and comes with support for a range of devices that are typically
found in the Internet of Things: 8-bit microcontrollers, 16-bit
microcontrollers and light-weight 32-bit processors.

RIOT is based on the following design principles: energy-efficiency, soft
real-time capabilities, small memory footprint, modularity, and uniform API
access, independent of the underlying hardware (with partial POSIX compliance).

RIOT is developed by an international open-source community which is
independent of specific vendors (e.g. similarly to the Linux community) and is
licensed with a non-viral copyleft license (LGPLv2.1), which allows indirect
business models around the free open-source software platform provided by RIOT.

About this release:
===================
This release provides a lot of new features, fixes and enhancements. Among
these has been a huge cleanup regarding cppcheck and documentation, and we're
pleased to announce that all remaining doxygen and cppcheck warnings have been
fixed.  We're also proud to present a Virtual File System layer and integration
of the SPIFFS file system.  A lot of work has gone into support for
STMicroelectronics's Nucleo family, with RIOT now supporting 28 (up from 13)
Nucleo boards.  And as always, there was a lot of under-the-hood cleanup, bug
fixing and documentation work.

About 200 pull requests with about 562 commits have been merged since the last release and about 23
issues have been solved. 32 people contributed with code in 91 days. 2697 files have been touched with
716950 insertions and 492623 deletions.

Notations used below:
=====================
+ means new feature/item
* means modified feature/item
- means removed feature/item

New features and changes
========================

Core
----
+ full C11 atomics support
+ rmutex, a recursive mutex implementation

API changes
-----------
* renamed NTOH*() -> ntoh*(), HTON*() -> hton*()
- removed gpioint API, which was unnused and obsoleted by periph/gpio
* renamed uuid module to luid

System libraries
----------------
+ VFS: virtual file system layer
+ fmt: add print_byte_hex(), fmt_lpad()
- 3DES: removed support as 3DES is considered legacy crypto

Networking
----------
+ emCute - a small MQTT-SN implementation
+ sock_dns: a simple DNS resolver

Packages
--------
+ SPIFFS, the first file system supported by RIOT's VFS layer
+ jerryscript, a Javascript interpreter

Drivers
-------
- added dynamixel server motor driver
- removed ltc4150 driver
- removed smb380 driver

Build System
------------
+ Experimental distributed building using Murdock
+ most makfiles moved from root into makefiles/
+ added submodule support

Special Thanks
==============
We like to give our special thanks to all the companies that provided us with their hardware for
porting and testing, namely the people from (in alphabeticalorder): Atmel, Freescale, Imagination
Technologies, Nordic, OpenMote, Phytec, SiLabs, UDOO, and Zolertia; and also companies that directly
sponsored development time: Cisco Systems, Eistec, Ell-i, Enigeering Spirit, Nordic, OTAkeys and Phytec.

More information
================
http://www.riot-os.org

Mailing lists
-------------
* RIOT OS kernel developers list
  devel@riot-os.org (http://lists.riot-os.org/mailman/listinfo/devel)
* RIOT OS users list
  users@riot-os.org (http://lists.riot-os.org/mailman/listinfo/users)
* RIOT commits
  commits@riot-os.org (http://lists.riot-os.org/mailman/listinfo/commits)
* Github notifications
  notifications@riot-os.org (http://lists.riot-os.org/mailman/listinfo/notifications)

IRC
---
* Join the RIOT IRC channel at: irc.freenode.net, #riot-os

License
=======
* Most of the code developed by the RIOT community is licensed under the GNU Lesser General Public
  License (LGPL) version 2.1 as published by the Free Software Foundation.
* Some external sources are published under a separate, LGPL compatible license
  (e.g. some files developedby SICS).

All code files contain licensing information.






RIOT-2017.01 - Release Notes
============================
RIOT is a multi-threading operating system which enables soft real-time capabilities and comes with
support for a range of devices that are typically found in the Internet of Things: 8-bit microcontrollers,
16-bit microcontrollers and light-weight 32-bit processors.

RIOT is based on the following design principles: energy-efficiency, soft real-time capabilities,
small memory footprint, modularity, and uniform API access, independent of the underlying hardware
(with partial POSIX compliance).

RIOT is developed by an international open-source community which is independent of specific vendors
(e.g. similarly to the Linux community) and is licensed with a non-viral copyleft license (LGPLv2.1),
which allows indirect business models around the free open-source software platform provided by RIOT.

About this release:
===================
This release provides a lot of new features, fixes and enhancements. Among others these features
contain an initial - still experimental - TCP implementation based on the GNRC network stack, support
for reading from and writing to SD cards, a new power management architecture as well additional third
party packages such as TweetNaCl, a cryptographic library, and Heatshrink a data compression library
optimized for embedded real-time systems.
We added support for new platforms including the Calliope mini, Maple mini, and a couple of STMs
Nucleo boards. Device support was extended by several new drivers, e.g., for NXP PN532 NFC, Microchip
MRF24J40 802.15.4 radio (experimental), or Bosch BME280 pressure/humidity/temperature sensor.
We completely refactored the SPI interface, allowing for internally handled hardware or software chip
select lines and shared bus usage for multiple devices with different SPI configurations.

About 278 pull requests with about 606 commits have been merged since the last release and about 84
issues have been solved. 44 people contributed with code in 87 days. 2230 files have been touched with
220275 insertions and 159840 deletions.


Notations used below:
=====================
+ means new feature/item
* means modified feature/item
- means removed feature/item

New features and changes
========================
General
-------
+ New power management architecture

Core
----
+ Initial (experimental) OpenOCD/GDB thread support
* Make Semaphore implementation IPC independent

API changes
-----------
* SPI driver interface (rework)
* Add Mutex lock with timeout parameter
* Xtimer allow for arbitrary frequency & additional convenience functions
* HDC1000 driver remodeling
* MMA8652 driver remodeling (MMA8x5x now)

System libraries
----------------
+ Lightweight CRC16 implementation
- Remove Twofish and RC5 implementation

Networking
----------
+ Initial (experimental) GNRC TCP implementation
* Provide sock-port for POSIX SOCKETS
* Provide sock-port for GCOAP
* Provide sock-port for UHCPC
* Provide sock_ip wrapper for LWIP
* Native: allow for multiple netdev_tap devices

Packages
--------
+ TweetNaCl: cryptographic library
+ Heatshrink: compression/decompression library
- Removed: OpenWSN

Platforms
---------
+ Support for Maple mini board
+ Support for ST Nucleo-32 F303 board
+ Support for ST Nucleo-32 F042 board
+ Support for Calliope mini board
- Drop support for PTTU platform

Drivers
-------
* Rework SPI driver interface
+ Peripheral flashrom driver interface
+ SD Card driver (SPI)
+ NXP PN532 NFC driver
+ Initial (experimental) Microchip MRF24J40 radio driver
+ JEDEC JC42.4 temperatur sensors
+ Bosch BME280 pressure, humidity and temperature sensor
* NXP MMA8x5x accelerometer (previously MMA8652)
* Unified STM32 RTC driver
* Unified STM32 UART driver
* Unified STM32 PWM driver
* Unified STM32 timer driver
* Unified NRF5x low power modes
+ Low power modes for the STM32F1 family
* Unified Kinetis low power modes
* Xbee port to netdev API
* W5100 port to netdev API
* NRF5x/'nrfmin' port to netdev API (w/o 6LoWPAN support currently)
* Refactor synchronous UART by new 'isrpipe' module

Build System
------------
+ Experimental Jenkins CI
* Python3 support for compile script (compile_test.py)

Other
-----
+ UUID module for central ID/address generation

Fixed Issues from the last release
==================================
#4388: POSIX sockets: open socket is bound to a specific thread
#4737: cortex-m: Hard fault after a thread exits
#4874: Using single RSSI_BASE_VALUE for all Atmel radios
#5034: gnrc_networking: offers txtsnd, does not print received packets
#5083: AVR8: Reboots after `return 0;`
#5719: cc2538: rf driver doesn't handle large packets
#5954: nRF52 uart_write gets stuck
#6036: tinydtls: DTLS randomly missing functions
#6037: pkg/nanocoap: native build fails on macOS
#6358: arduino uno : xtimer accuracy problem

Known Issues
============
Networking related issues
-------------------------
#3075: nhdp: unnecessary microsecond precision: NHDP works with timer values of microsecond precision
       which is not required. Changing to lower precision would save some memory.
#4048: potential racey memory leak: According to the packet buffer stats, flood-pinging a multicast
       destination may lead to a memory leak due to a race condition. However, it seems to be a rare