Review of Azure RTOS ThreadX Real-Time Operating System on STM32 platforms
DOI:
https://doi.org/10.4108/eetsmre.11710Keywords:
Real-time operating systems, Azure RTOS ThreadX, STM32 microcontrollers, deterministic scheduling, inter-thread communication, thread synchronization, memory management, ARM Cortex-MAbstract
Real-time operating systems (RTOS) play a critical role in modern embedded systems by providing deterministic execution, predictable timing behavior, and efficient use of limited hardware resources. These properties are especially important in industrial automation, energy control, and safety-oriented applications, where reliable timing behavior is required. This article focuses on Azure RTOS ThreadX, a lightweight RTOS, and examines its core real-time mechanisms, including scheduling, inter-thread communication and synchronization, and memory management. Particular attention is given to the integration of ThreadX with STM32 microcontrollers based on ARM Cortex-M architectures, which are widely adopted in industrial and energy-related embedded platforms. Therefore, a structured literature survey is conducted using peer-reviewed publications, official technical documentation, and industrial reports to analyze and compare ThreadX with other embedded RTOS solutions. The analysis indicates that, on typical STM32 platforms using ARM Cortex-M cores, ThreadX achieves context-switch latencies in the low microsecond range while maintaining a small kernel footprint suitable for resource-constrained devices. These characteristics enable reliable and predictable operation in industrial and safety-critical embedded systems, while also highlighting challenges related to scalability, mixed-criticality workloads, and energy-aware scheduling that motivate future research.
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