Scheduling APIs

RTOS APIs

The RTOS APIs handle creation and destruction of threads in Arm Mbed OS, as well as mechanisms for safe interthread communication. Threads are a core component of Mbed OS (even your main function starts in a thread of its own), so understanding how to work with them is an important part of developing applications for Mbed OS.

• ConditionVariable: The ConditionVariable class provides a mechanism to safely wait for or signal a single state change. You cannot call ConditionVariable functions from ISR context.
• EventFlags: An event channel that provides a generic way of notifying other threads about conditions or events. You can call some EventFlags functions from ISR context, and each EventFlags object can support up to 31 flags.
• IdleLoop: Background system thread, executed when no other threads are ready to run.
• Kernel interface functions: Kernel namespace implements functions to control or read RTOS information, such as tick count.
• Mail: The API that provides a queue combined with a memory pool for allocating messages.
• Mutex: The class used to synchronize the execution of threads.
• Queue: The class that allows you to queue pointers to data from producer threads to consumer threads.
• Semaphore: The class that manages thread access to a pool of shared resources of a certain type.
• ThisThread: The class with which you can control the current thread.
• Thread: The class that allows defining, creating and controlling parallel tasks.

Event handling APIs

If you are using the bare metal profile, the only APIs of the RTOS group you can use are those that do not rely on the RTX:

• Event: The queue to store events, extract them and execute them later.
• EventQueue: The class that provides a flexible queue for scheduling events.
• UserAllocatedEvent: The class that provides APIs to create and configure static events

Note that you can also use these APIs while using the full, RTOS-based profile.