RIOT is a real-time multi-threading operating system that supports a range of devices that are typically found in the Internet of Things (IoT): 8-bit, 16-bit and 32-bit microcontrollers.
RIOT is based on the following design principles: energy-efficiency, real-time capabilities, small memory footprint, modularity, and uniform API access, independent of the underlying hardware (this API offers 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). RIOT is licensed with LGPLv2.1, a copyleft license which fosters indirect business models around the free open-source software platform provided by RIOT, e.g. it is possible to link closed-source code with the LGPL code.
RIOT is based on a microkernel architecture, and provides features including, but not limited to:
- a preemptive, tickless scheduler with priorities
- flexible memory management
- high resolution, long-term timers
- support 100+ boards based on AVR, MSP430, ESP8266, MIPS, ARM7 and ARM Cortex-M
- the native port allows to run RIOT as-is on Linux, BSD, and MacOS. Multiple instances of RIOT running on a single machine can also be interconnected via a simple virtual Ethernet bridge
- 6LoWPAN (RFC4944, RFC6282, and RFC6775)
- RPL (storing mode, P2P mode)
The 2019.04 release includes a number of new features including porting of riotboot to a number of new platforms, 802.15.4 support on the nRF52, and the ability for firmware to flash images into a separate boot slot. Support for several new boards and new sensors was added. Additionally, this release contains a number of bug fixes and test improvements.
About 320 pull requests with about 569 commits have been merged since the last release and about 40 issues have been solved. 44 people contributed with code in 88 days. Approximately 825 files have been touched with 32716 insertions and 5149 deletions.