have ports for most popular processors and boards in the market and are suitable for use in safety critical embedded systems such as aviation, medical systems, and nuclear installations. A μC/OS-III port involves writing or changing the contents of three kernel specific files: OS_CPU.H, OS_CPU_A.ASM, and OS_CPU_C.C. Finally create or change a board support package (BSP) for the evaluation board or target board being used. A μC/OS-III port is similar to a μC/OS-II port. There are significantly more ports than listed here, and ports are subject to continuous development. Both μC/OS-II and μC/OS-III are supported by popular SSL/TLS libraries such as wolfSSL, which ensure security across all connections. Licensing change After acquisition by Silicon Labs, Micrium in 2020 changed to open-source model licensing in February 2020. This includes uC/OS III, all prior versions, all components: USB, file system, GUI, TCP/IP, etc. Documentation and support Support is available via a typical support forum, and several comprehensive books, several tailored to a given microcontroller architecture and development platform, as free PDFs, or as low-cost purchase in hard-cover. Paid support is available from Micrium and other parties. References Sources Protocol Support for μC/OS-II from Fusion Embedded Micrium-uCOS-III-UsersManual 1st Edition uC/OS-III: The Real-Time Kernel for the Renesas RX62N External links Summary of Commonly Used uC/OS-II Functions and Data Structures NiosII GCC with MicroC/OS μC/OS-II Reference Manual How to Get a μC/OS-II Application Running Real-time operating systems Embedded operating systems ARM operating systems Microkernel-based operating systems Microkernels