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diff --git a/Smol Watch Project/My Project/hal/documentation/timer.rst b/Smol Watch Project/My Project/hal/documentation/timer.rst deleted file mode 100644 index c5ca63d1..00000000 --- a/Smol Watch Project/My Project/hal/documentation/timer.rst +++ /dev/null @@ -1,52 +0,0 @@ -============================ -The Timer driver (bare-bone) -============================ - -The Timer driver provides means for delayed and periodical function invocation. - -A timer task is a piece of code (function) executed at a specific time or periodically by the timer after the task has -been added to the timers task queue. The execution delay or period is set in ticks, where one tick is defined as a -configurable number of clock cycles in the hardware timer. Changing the number of clock cycles in a tick automatically -changes execution delays and periods for all tasks in the timers task queue. - -A task has two operation modes, single-shot or repeating mode. In single-shot mode the task is removed from the task queue -and then is executed once, in repeating mode the task reschedules itself automatically after it has executed based on -the period set in the task configuration. -In single-shot mode a task is removed from the task queue before its callback is invoked. It allows an application to -reuse the memory of expired task in the callback. - -Each instance of the Timer driver supports infinite amount of timer tasks, only limited by the amount of RAM available. - -Features --------- -* Initialization and de-initialization -* Starting and stopping -* Timer tasks - periodical invocation of functions -* Changing and obtaining of the period of a timer - -Applications ------------- -* Delayed and periodical function execution for middle-ware stacks and applications. - -Dependencies ------------- -* Each instance of the driver requires separate hardware timer capable of generating periodic interrupt. - -Concurrency ------------ -The Timer driver is an interrupt driven driver.This means that the interrupt that triggers a task may occur during -the process of adding or removing a task via the driver's API. In such case the interrupt processing is postponed -until the task adding or removing is complete. - -The task queue is not protected from the access by interrupts not used by the driver. Due to this -it is not recommended to add or remove a task from such interrupts: in case if a higher priority interrupt supersedes -the driver's interrupt, adding or removing a task may cause unpredictable behavior of the driver. - -Limitations ------------ -* The driver is designed to work outside of an operating system environment, the task queue is therefore processed in interrupt context which may delay execution of other interrupts. -* If there are a lot of frequently called interrupts with the priority higher than the driver's one, it may cause delay for triggering of a task. - -Knows issues and workarounds ----------------------------- -Not applicable |