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Mutexes & Semaphores

Coordinating concurrent tasks: a mutex for mutual exclusion (ownership + priority inheritance) vs a semaphore for signaling and counting, and why you give a semaphore from an ISR, not take a mutex.

25 min read

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5 interview questions on this topic

Each one opens a full worked answer.

What's the difference between a mutex and a semaphore?How do you safely signal a task from an ISR?Why shouldn't you use a mutex (instead of a semaphore) to signal an event from an ISR?What is a counting semaphore good for?What are the common bugs with locks in an RTOS?

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Mutexes & Semaphores | EmbeddedPrep.io