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os_core.c contains core functionality for µC/OS-III such as OSInit() to initialize µC/OS-III, OSSched() for the task level scheduler, OSIntExit() for the interrupt level scheduler, pend list (or wait list) management (see Pend Lists (or Wait Lists)), ready list management (see Ready List), and more.
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os_mem.c contains code for the µC/OS-III fixed-size memory manager, see Memory Management ( API Changes).
os_msg.c contains code to handle messages. µC/OS-III provides message queues and task specific message queues. os_msg.c provides common code for these two services. See Message Passing.
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