Zephyr RTOS for Synopsys ARC Processors

Zephyr RTOS for Synopsys ARC® processors (ARC Zephyr) offers all of the benefits of open-source software, including complete source code and a large, growing user community. ARC Zephyr allows software developers to leverage a small-footprint real-time kernel for use in resource-constrained embedded systems together, while scalable to larger systems with a full range of support for communications protocols and file systems. ARC Zephyr runs on up-to-date 32- and 64-bit ARC processors, including ARC EMx, HS3x, HS4x, HS5x, HS6x and VPX processor families. The latest version of ARC Zephyr is available from the official Zephyr Project repository at GitHub.

The following features of ARC processors are supported in ARC Zephyr:

  • Closely-coupled memories (ICCM & DCCM)
  • Hardware-assisted unaligned memory access
  • Interrupts with multiple priority levels
  • Hardware floating-point unit (FPU)
  • Symmetric multiprocessing (SMP)
  • Hardware-assisted stack-checking
  • Hardware-assisted atomic operations
  • DSP ISA, AGU and XY-memory extensions
  • Memory protection unit (MPU)

More detailed information is available in the Zephyr Project documentation.

ARC Zephyr is tested with Zephyr’s extensive built-in test suite on up-to-date Synopsys hardware development platforms, as well as on Synopsys ARC nSIM and open source QEMU simulators.


  • ARC Zephyr is part of the official Zephyr Project repository since initial Zephyr Project launch
  • Synopsys representatives actively participate in multiple Zephyr Project committees including the Technical Steering Committee
  • Allows developers to leverage a full-featured scalable RTOS runtime environment
  • Supports building with open source ARC GNU toolchain or Synopsys MetaWare toolchain
  • Branches with long-term support are available for ARC users
  • Maintained and tested by Synopsys software engineers