There are two types of timers, one-shot timers, and auto-reload timers. A one-shot timer can execute its callback function only once.
cmsis
FreeRTOS TUTORIAL #4 -> Using Counting Semaphore
Counting semaphore can be used to control the access to the resource. To obtain control of a resource, a task must first obtain a semaphore.
FreeRTOS Tutorial #3 -> How to use Binary Semaphore
A Binary Semaphore is called Binary because either it is there (‘1’) or it is not (‘0’). There is no third condition in it. So, a Task either have it or not