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RTX Real-Time Operating System

CMSIS-RTOS compliant RTX Implementation
Version 4.70

This version of RTX contains the CMSIS-RTOS API interface as it is described in CMSIS Version 3.20. For details on CMSIS 3.20 refer to under Download Specification.

This software is provided under a BSD License and can be freely used and distributed.


  • New functions for short timeouts in microsecond resolution
  • osTimerCreate can be called prior to osKernelStart (but after osKernelInitialize)
  • initialization of external timer corrected for Cortex-M0/M0+/M1
  • Message/Mail Queue behavior corrected when timeout expires

Keil MDK v6 Community Edition is now available

Complete the following form to download the Keil software development tools.

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