Atomthreads is a free, lightweight, portable, real-time scheduler for embedded systems.


  • Preemptive scheduler
  • Unlimited threads
  • 255 priority levels
  • Round-robin timeslicing at same priority level
  • Semaphores
  • Mutexes (recursive with thread-ownership)
  • Queues
  • Timers
  • All primitives (Semaphores, Mutexes, Queues) support Blocking, Non-Blocking and Block with Timeout APIs
  • Safe APIs prevent blocking calls when at interrupt context
  • Thread stack usage analysis
  • Automated test suite provides evidence of reliable functionality

Atomthreads Platforms

  • AVR

Atomthreads Components

  • None