I’ve started a project where I mix task, co-rutines and semaphores but after a while it reboots. I think the problem may be because I try to get the semaphore from inside the co-rutines. Can anybody help me if is it possible or should be avoided ? Many thanks.

You cannot share a queue between a task and a coroutine so if this is what you are doing it could be the source of your problem. Semaphores use queues.