*
* For a task to yield it must return, thus each task should have persistent data marked with the static attribute.
*
+ * Each LUFA scheduler task should be written similar to an ISR; it should execute quickly (so that no one task
+ * hogs the processor, preventing another from running before some sort of timeout is exceeded). Unlike normal RTOS
+ * tasks, each LUFA scheduler task is a regular function, and thus must be designed to be called, and designed to
+ * return to the calling scheduler function repeatedly. Data which must be preserved between task calls should be
+ * declared as global or (preferably) as a static local variable inside the task.
+ *
+ * The scheduler consists of a task list, listing all the tasks which can be executed by the scheduler. Once started,
+ * each task is then called one after another, unless the task is stopped by another running task or interrupt.
+ *
* Usage Example:
* \code
* #include <LUFA/Scheduler/Scheduler.h>
*
- * TASK(MyTask1);
- * TASK(MyTask2);
+ * TASK(MyTask1); // Task prototype
+ * TASK(MyTask2); // Task prototype
*
* TASK_LIST
* {
- * { .Task = MyTask1, .TaskStatus = TASK_RUN, .GroupID = 1 },
- * { .Task = MyTask2, .TaskStatus = TASK_RUN, .GroupID = 1 },
+ * { .Task = MyTask1, .TaskStatus = TASK_RUN, .GroupID = 1 },
+ * { .Task = MyTask2, .TaskStatus = TASK_RUN, .GroupID = 1 },
* }
*
* int main(void)
* {
- * Scheduler_Start();
+ * Scheduler_Init();
+ *
+ * // Other initialisation here
+ *
+ * Scheduler_Start();
* }
*
* TASK(MyTask1)
* {
- * // Implementation Here
+ * // Task implementation here
* }
*
* TASK(MyTask2)
* {
- * // Implementation Here
+ * // Task implementation here
* }
* \endcode
*
+ * If desired, the LUFA scheduler <b>does not need to be used</b> in a LUFA powered application. A more conventional
+ * approach to application design can be used, or a proper scheduling RTOS inserted in the place of the LUFA scheduler.
+ * In the case of the former the USB task must be run manually repeatedly to maintain USB communications, and in the
+ * case of the latter a proper RTOS task must be set up to do the same.
+ *
* @{
*/
#define __SCHEDULER_H__
/* Includes: */
- #include <avr/io.h>
+ #include <stdint.h>
#include <stdbool.h>
#include <util/atomic.h>
*/
void Scheduler_Start(void);
- /** Initializes the scheduler so that the scheduler functions can be called before the scheduler itself
+ /** Initialises the scheduler so that the scheduler functions can be called before the scheduler itself
* is started. This must be executed before any scheduler function calls other than Scheduler_Start(),
* and can be omitted if no such functions could be called before the scheduler is started.
*/
TaskPtr_t Task; /**< Pointer to the task to execute. */
bool TaskStatus; /**< Status of the task (either TASK_RUN or TASK_STOP). */
uint8_t GroupID; /**< Group ID of the task so that its status can be changed as a group. */
- } TaskEntry_t;
+ } TaskEntry_t;
/* Global Variables: */
/** Task entry list, containing the scheduler tasks, task statuses and group IDs. Each entry is of type
* Usage Example:
* \code
* static SchedulerDelayCounter_t DelayCounter = 10000; // Force immediate run on start-up
- *
+ *
* // Task runs every 10000 ticks, 10 seconds for this demo
* if (Scheduler_HasDelayElapsed(10000, &DelayCounter))
* {
*/
bool Scheduler_HasDelayElapsed(const uint16_t Delay,
SchedulerDelayCounter_t* const DelayCounter)
- ATTR_WARN_UNUSED_RESULT ATTR_NON_NULL_PTR_ARG(2);
+ ATTR_WARN_UNUSED_RESULT ATTR_NON_NULL_PTR_ARG(2);
/** Sets the task mode for a given task.
*
* \param[in] Task Name of the task whose status is to be changed.
* \param[in] TaskStatus New task status for the task (\ref TASK_RUN or \ref TASK_STOP).
*/
- void Scheduler_SetTaskMode(const TaskPtr_t Task, const bool TaskStatus);
+ void Scheduler_SetTaskMode(const TaskPtr_t Task,
+ const bool TaskStatus);
/** Sets the task mode for a given task group ID, allowing for an entire group of tasks to have their
* statuses changed at once.
* \param[in] GroupID Value of the task group ID whose status is to be changed.
* \param[in] TaskStatus New task status for tasks in the specified group (\ref TASK_RUN or \ref TASK_STOP).
*/
- void Scheduler_SetGroupTaskMode(const uint8_t GroupID, const bool TaskStatus);
+ void Scheduler_SetGroupTaskMode(const uint8_t GroupID,
+ const bool TaskStatus);
- /* Private Interface - For use in library only: */
+ /* Private Interface - For use in library only: */
#if !defined(__DOXYGEN__)
/* Macros: */
#define TOTAL_TASKS (sizeof(Scheduler_TaskList) / sizeof(TaskEntry_t))
projects / pub / USBasp.git / blobdiff