8bitgeek / BabyRTOS

A minimal pre-emptive RTOS kernel, based on the ARM Cortex-M4 processor.

BabyRTOS

A pre-emptive priority-based Real-Time Operating System (RTOS), based on the ARM Cortex-M4 processor.

Major features of the implementation includes,

• Up to 63 task priorities.
• Time-sharing (i.e, round-robin scheduling) between tasks of equal priority.
• Support for multiple OS resources, including OS_mutex, OS_semaphore, and OS_queue.
• Priority inheritance by mutex-locking tasks, by ceiling all waiting tasks.

Notes

• Under /src is a sample application, based on the STM32F401CC micro-controller.
• The implementation resides under,
  • /src/OS/OS.c and,
  • /src/OS/OS.h.
• Other implementation dependencies are,
  • /src/MCAL/UTIL/Std_Types.h,
  • /src/UTIL/LinkedList and,
  • /src/UTIL/Queue.
• The implementation uses the SysTick ISR for tracking OS ticks.
  • Its clock configuration is the responsibility of the Application.
  • The interrupt is automatically enabled by OS_init.
  • The timer is automatically started by OS_start.
• Zero interrupt-priority is reserved, and should not be assigned to any other interrupt.
• Interrupt pre-emption in the system is automatically disabled by OS_init.
• All system resources (i.e, tasks, mutexes, semaphores, queues) must be zero-initialized (i.e, defined as global variables).
• Use make -r -s build or make -r -s clean while in the /src directory.

Links

• Codebase
• Documentation
• Implementation Guide