/*
LUFA Library
- Copyright (C) Dean Camera, 2010.
-
+ Copyright (C) Dean Camera, 2011.
+
dean [at] fourwalledcubicle [dot] com
- www.fourwalledcubicle.com
+ www.lufa-lib.org
*/
/*
- Copyright 2010 Dean Camera (dean [at] fourwalledcubicle [dot] com)
+ Copyright 2011 Dean Camera (dean [at] fourwalledcubicle [dot] com)
- Permission to use, copy, modify, distribute, and sell this
+ Permission to use, copy, modify, distribute, and sell this
software and its documentation for any purpose is hereby granted
- without fee, provided that the above copyright notice appear in
+ without fee, provided that the above copyright notice appear in
all copies and that both that the copyright notice and this
- permission notice and warranty disclaimer appear in supporting
- documentation, and that the name of the author not be used in
- advertising or publicity pertaining to distribution of the
+ permission notice and warranty disclaimer appear in supporting
+ documentation, and that the name of the author not be used in
+ advertising or publicity pertaining to distribution of the
software without specific, written prior permission.
The author disclaim all warranties with regard to this
*
* \deprecated This module is deprecated and will be removed in a future library release.
*/
-
-/** @defgroup Group_Scheduler Simple Task Scheduler - LUFA/Scheduler/Scheduler.h
+
+/** \defgroup Group_Scheduler Simple Task Scheduler - LUFA/Scheduler/Scheduler.h
+ * \brief Simple round-robbin pseudo-task scheduler.
*
* \deprecated This module is deprecated and will be removed in a future library release.
*
* The following files must be built with any user project that uses this module:
* - LUFA/Scheduler/Scheduler.c <i>(Makefile source module name: LUFA_SRC_SCHEDULER)</i>
*
- * \section Module Description
+ * \section Sec_ModDescription Module Description
* Simple round-robbin cooperative scheduler for use in basic projects where non real-time tasks need
* to be executed. Each task is executed in sequence, and can be enabled or disabled individually or as a group.
*
- * For a task to yield it must return, thus each task should have persistent data marked with the static attribute.
+ * For a task to yield it must \c return, thus each task should have persistent data marked with the \c static keyword.
+ *
+ * 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 \c 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.
+ *
* @{
*/
-
+
#ifndef __SCHEDULER_H__
#define __SCHEDULER_H__
/* Includes: */
- #include <stdint.h>
- #include <stdbool.h>
-
- #include <util/atomic.h>
-
#include "../Common/Common.h"
/* Enable C linkage for C++ Compilers: */
* \endcode
*/
#define TASK(name) void name (void)
-
- /** Defines a task list array, containing one or more task entries of the type TaskEntry_t. Each task list
+
+ /** Defines a task list array, containing one or more task entries of the type \ref TaskEntry_t. Each task list
* should be encased in curly braces and ended with a comma.
*
* Usage Example:
* }
* \endcode
*/
- #define TASK_LIST TaskEntry_t Scheduler_TaskList[] =
-
+ #define TASK_LIST TaskEntry_t Scheduler_TaskList[] =
+
/** Constant, giving the maximum delay in scheduler ticks which can be stored in a variable of type
* \ref SchedulerDelayCounter_t.
*/
/** Task status mode constant, for passing to \ref Scheduler_SetTaskMode() or \ref Scheduler_SetGroupTaskMode(). */
#define TASK_STOP false
-
+
/* Pseudo-Function Macros: */
#if defined(__DOXYGEN__)
/** Starts the scheduler in its infinite loop, executing running tasks. This should be placed at the end
- * of the user application's main() function, as it can never return to the calling function.
+ * of the user application's \c main() function, as it can never return to the calling function.
*/
void Scheduler_Start(void);
-
- /** Initializes 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(),
+
+ /** 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 \ref Scheduler_Start(),
* and can be omitted if no such functions could be called before the scheduler is started.
*/
void Scheduler_Init(void);
/* Type Defines: */
/** Type define for a pointer to a scheduler task. */
typedef void (*TaskPtr_t)(void);
-
+
/** Type define for a variable which can hold a tick delay value for the scheduler up to the maximum delay
* possible.
*/
- typedef uint16_t SchedulerDelayCounter_t;
-
+ typedef uint_least16_t SchedulerDelayCounter_t;
+
/** \brief Scheduler Task List Entry Structure.
*
* Structure for holding a single task's information in the scheduler task list.
*/
typedef struct
{
- 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;
+ TaskPtr_t Task; /**< Pointer to the task to execute. */
+ bool TaskStatus; /**< Status of the task (either TASK_RUN or TASK_STOP). */
+ uint_least8_t GroupID; /**< Group ID of the task so that its status can be changed as a group. */
+ } TaskEntry_t;
/* Global Variables: */
/** Task entry list, containing the scheduler tasks, task statuses and group IDs. Each entry is of type
- * TaskEntry_t and can be manipulated as desired, although it is preferential that the proper Scheduler
+ * \ref TaskEntry_t and can be manipulated as desired, although it is preferred that the proper Scheduler
* functions should be used instead of direct manipulation.
*/
- exter TaskEntry_t Scheduler_TaskList[];
-
+ extern TaskEntry_t Scheduler_TaskList[];
+
/** Contains the total number of tasks in the task list, irrespective of if the task's status is set to
* \ref TASK_RUN or \ref TASK_STOP.
*
* \note This value should be treated as read-only, and never altered in user-code.
*/
- extern volatile uint8_t Scheduler_TotalTasks;
+ extern volatile uint_least8_t Scheduler_TotalTasks;
/** Contains the current scheduler tick count, for use with the delay functions. If the delay functions
* are used in the user code, this should be incremented each tick period so that the delays can be
ATTR_NON_NULL_PTR_ARG(1) ATTR_ALWAYS_INLINE;
static inline void Scheduler_ResetDelay(SchedulerDelayCounter_t* const DelayCounter)
{
- ATOMIC_BLOCK(ATOMIC_RESTORESTATE)
- {
- *DelayCounter = Scheduler_TickCounter;
- }
+ uint_reg_t CurrentGlobalInt = GetGlobalInterruptMask();
+ GlobalInterruptDisable();
+
+ *DelayCounter = Scheduler_TickCounter;
+
+ SetGlobalInterruptMask(CurrentGlobalInt);
}
-
+
/* Function Prototypes: */
/** Determines if the given tick delay has elapsed, based on the given delay period and tick counter value.
*
* \param[in] Delay The delay to test for, measured in ticks.
* \param[in] DelayCounter The counter which is storing the starting tick value for the delay.
*
- * \return Boolean true if the delay has elapsed, false otherwise.
+ * \return Boolean \c true if the delay has elapsed, \c false otherwise.
*
* 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))
* {
* }
* \endcode
*/
- bool Scheduler_HasDelayElapsed(const uint16_t Delay,
+ bool Scheduler_HasDelayElapsed(const uint_least16_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 uint_least8_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))
- #define MAX_DELAYCTR_COUNT 0xFFFF
+ #define MAX_DELAYCTR_COUNT UINT_LEAST16_MAX
/* Inline Functions: */
- static inline void Scheduler_InitScheduler(const uint8_t TotalTasks) ATTR_ALWAYS_INLINE;
- static inline void Scheduler_InitScheduler(const uint8_t TotalTasks)
+ static inline void Scheduler_InitScheduler(const uint_least8_t TotalTasks) ATTR_ALWAYS_INLINE;
+ static inline void Scheduler_InitScheduler(const uint_least8_t TotalTasks)
{
Scheduler_TotalTasks = TotalTasks;
}
-
- static inline void Scheduler_GoSchedule(const uint8_t TotalTasks) ATTR_NO_RETURN ATTR_ALWAYS_INLINE ATTR_DEPRECATED;
- static inline void Scheduler_GoSchedule(const uint8_t TotalTasks)
+
+ static inline void Scheduler_GoSchedule(const uint_least8_t TotalTasks)
+ ATTR_NO_RETURN ATTR_ALWAYS_INLINE ATTR_DEPRECATED;
+ static inline void Scheduler_GoSchedule(const uint_least8_t TotalTasks)
{
Scheduler_InitScheduler(TotalTasks);
for (;;)
{
TaskEntry_t* CurrTask = &Scheduler_TaskList[0];
-
+
while (CurrTask != &Scheduler_TaskList[TotalTasks])
{
if (CurrTask->TaskStatus == TASK_RUN)
}
}
#endif
-
+
/* Disable C linkage for C++ Compilers: */
#if defined(__cplusplus)
}
#endif
-
+
#endif
/** @} */
+