Run-Time System for Functional Safety

Arm FuSa RTS is a set of embedded software components qualified for use in the most safety-critical applications in automotive, medical and industrial systems.

FuSa RTS components, safety-qualified Arm C/C++ compiler and Arm Keil MDK tools are natively integrated together and significantly simplify system design, development, validation and certification processes for safety applications.

Request more info

Supported safety standards

Arm FuSa RTS is certified for the following safety standards:

  • Automotive: ISO26262, ASIL D
  • Industrial: IEC61508, SIL 3
  • Railway: EN50128, SIL 4
  • Medical: IEC62304, Class C

FuSa RTS safety compliance is confirmed by the TÜV Süd Certificate.

Supported devices

FuSa RTS fully utilizes advanced hardware features that Arm specifies for its processors. It provides support for devices with the following Arm Cortex-M cores:

  • Cortex-M0/M0+
  • Cortex-M3
  • Cortex-M4
  • Cortex-M7

FuSa RTS Components

Arm FuSa RTS package contains components as outlined by the red dotted line on the figure below:

  • FuSa CMSIS-Core: vendor-independent software interface to the processor resources.

  • FuSa C library: a subset of the C library functions verified for safety-critical applications.

  • Safety Package: documentation set explaining the usage of FuSa RTS in safety context.

Related tools from Arm

Arm equips software engineers with professional tools that support safety development process and simplify creation, analysis and verification of complex embedded applications in safety context. 

Arm Keil MDK

FuSa RTS is developed and verified using Arm Keil MDK and natively integrates with it.

MDK-Professional edition contains the µVision IDE and debugger with built-in tools for code coverage tests and execution profiling. It also provides access to the safety Arm C/C++ compiler used for FuSa RTS validation.

Keil MDK enables static code analysis and MISRA compliance checking via integration with third-party verification tools.

Learn more about MDK safety aspects on

Safety-qualified Arm C/C++ compiler

FuSa RTS has been validated with safety-qualified Arm C/C++ compiler that for many years have been used in safety-related applications across a wide range of verticals, including automotive, medical, industrial, avionics and railway.

MDK-Professional edition provides access to the Arm compiler safety package without additional costs.

More about Arm C/C++ Compiler for functional safety