The use of a real-time operating system (RTOS) in a safety-critical system requires that the RTOS component is also subjected to rigorous testing. In cases where regulatory certification is required, this also implies specific documentation and testing processes for the targeted safety standards.

FUSA RTX RTOS structure

To enable and streamline product safety certification, Arm offers the FuSa RTX RTOS as part of the FuSa RTS package, qualified for use in automotive, industrial, railroad and medical applications:

  • It is a deterministic real-time operating system (RTOS) that reliably manages multiple application threads with priority-based, preemptive scheduling.
  • It provides all the services needed in complex real-time applications, such as threads, timers, memory and object management, message exchange, and others.
  • The kernel is highly optimized for the Cortex-M architecture and has several provisions that naturally improve the reliability of an embedded application.

FuSa RTS RTOS Features

Strictly validated code

RTX is written in C using C99 language extensions with MISRA C:2012 guidelines being applied to it. FuSa RTX code has gone through stringent safety analysis and rigorous testing. It is approved for use in applications with the most demanding safety integrity levels (SIL). See FuSa RTS for the list of applicable safety standards.

Designed for engineering efficiency

Fusa RTX RTOS only has a small memory footprint. It requires minimum amount of system memory, starting from 5 KB ROM. It has tick-less operation mode for low power devices.

Easy to configure and use

FuSa RTX is provided as a CMSIS component and can be easily managed in a µVision Run-Time Environment dialog. With the configuration wizard support, FuSa RTX provides a number of configuration parameters for the kernel operation as well as for the RTX objects such as threads, mutex and semaphores. The integrated support of the MDK configuration wizard makes the parameter settings clear and intuitive.

Reliable execution

RTX utilizes the LDEX/STEX instruction available on most Cortex-M processors and therefore user interrupts are never disabled. This allows time-deterministic interrupt execution.

Safe operation

The RTOS kernel executes in handler mode with stack separated from user threads which avoids unexpected stack loads. RTX implements a software stack overflow checking that traps stack overruns. Object identifiers are validated at run-time for type-mismatches and are protected from inadvertently accesses by the user application.

Flexible memory management

Dedicated fixed-size memory blocks for each object type avoids memory fragmentation during run-time and makes object creation and destruction time deterministic. The user application may rely on static memory for kernel objects, which guarantees that the RTOS system can never run out of storage during run-time.

RTOS for Middleware for Cortex-M

Format: online training
Duration: 2 days, from 9:00 a.m. to 1 p.m.
Language of instruction: German (presentation slides in English)
Costs: 650.00 EUR (early bird discount 100 EUR)