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when a task is switched out, what will happen to its IOs?

Posted by sdfewa on January 21, 2018

If task A reads/writes from/to IOs and the scheduler switchs it to a higher priority task B which doesn't touch any IOs task used. Do they keep their state in general? There is no any kind of reset action during the context saving/switching, right? I assume task A doesn't have critical sections or has finished its critial sections.

And further, task B can do anything she wants to the IOs until task B is out?

when a task is switched out, what will happen to its IOs?

Posted by richard_damon on January 21, 2018

FreeRTOS itself will know nothing about the I/Os and tasks can do what every they want to them. Unless you write code in the trace macros, or modify the files in some way, I/O ports will have no idea of what task is runing, so a task switch won't affect the I/Os.

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