From 475b1cbd6a8b81b33c7a50cc6d51ddee55e666d1 Mon Sep 17 00:00:00 2001
From: richardbarry <richardbarry@1d2547de-c912-0410-9cb9-b8ca96c0e9e2>
Date: Thu, 21 Nov 2013 21:46:08 +0000
Subject: [PATCH] Add event_groups.c and associated functions in other core
 files. Added xTimerPendCallbackFromISR() to provide a centralised deferred
 interrupt handling mechanism. Add xPortGetLowestEverFreeHeapSize() to
 heap_4.c.

git-svn-id: https://svn.code.sf.net/p/freertos/code/trunk@2112 1d2547de-c912-0410-9cb9-b8ca96c0e9e2
---
 FreeRTOS/Source/event_groups.c            | 442 +++++++++++++++
 FreeRTOS/Source/include/FreeRTOS.h        |  19 +-
 FreeRTOS/Source/include/event_groups.h    | 625 ++++++++++++++++++++++
 FreeRTOS/Source/include/list.h            |  26 +-
 FreeRTOS/Source/include/portable.h        |   1 +
 FreeRTOS/Source/include/projdefs.h        |   6 +-
 FreeRTOS/Source/include/task.h            |  39 +-
 FreeRTOS/Source/include/timers.h          |  96 +++-
 FreeRTOS/Source/portable/MemMang/heap_4.c |  12 +
 FreeRTOS/Source/tasks.c                   | 123 ++++-
 FreeRTOS/Source/timers.c                  | 208 ++++---
 11 files changed, 1514 insertions(+), 83 deletions(-)
 create mode 100644 FreeRTOS/Source/event_groups.c
 create mode 100644 FreeRTOS/Source/include/event_groups.h

diff --git a/FreeRTOS/Source/event_groups.c b/FreeRTOS/Source/event_groups.c
new file mode 100644
index 000000000..eb186c191
--- /dev/null
+++ b/FreeRTOS/Source/event_groups.c
@@ -0,0 +1,442 @@
+/*
+    FreeRTOS V7.6.0 - Copyright (C) 2013 Real Time Engineers Ltd.
+    All rights reserved
+
+    VISIT http://www.FreeRTOS.org TO ENSURE YOU ARE USING THE LATEST VERSION.
+
+    ***************************************************************************
+     *                                                                       *
+     *    FreeRTOS provides completely free yet professionally developed,    *
+     *    robust, strictly quality controlled, supported, and cross          *
+     *    platform software that has become a de facto standard.             *
+     *                                                                       *
+     *    Help yourself get started quickly and support the FreeRTOS         *
+     *    project by purchasing a FreeRTOS tutorial book, reference          *
+     *    manual, or both from: http://www.FreeRTOS.org/Documentation        *
+     *                                                                       *
+     *    Thank you!                                                         *
+     *                                                                       *
+    ***************************************************************************
+
+    This file is part of the FreeRTOS distribution.
+
+    FreeRTOS is free software; you can redistribute it and/or modify it under
+    the terms of the GNU General Public License (version 2) as published by the
+    Free Software Foundation >>!AND MODIFIED BY!<< the FreeRTOS exception.
+
+    >>! NOTE: The modification to the GPL is included to allow you to distribute
+    >>! a combined work that includes FreeRTOS without being obliged to provide
+    >>! the source code for proprietary components outside of the FreeRTOS
+    >>! kernel.
+
+    FreeRTOS is distributed in the hope that it will be useful, but WITHOUT ANY
+    WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+    FOR A PARTICULAR PURPOSE.  Full license text is available from the following
+    link: http://www.freertos.org/a00114.html
+
+    1 tab == 4 spaces!
+
+    ***************************************************************************
+     *                                                                       *
+     *    Having a problem?  Start by reading the FAQ "My application does   *
+     *    not run, what could be wrong?"                                     *
+     *                                                                       *
+     *    http://www.FreeRTOS.org/FAQHelp.html                               *
+     *                                                                       *
+    ***************************************************************************
+
+    http://www.FreeRTOS.org - Documentation, books, training, latest versions,
+    license and Real Time Engineers Ltd. contact details.
+
+    http://www.FreeRTOS.org/plus - A selection of FreeRTOS ecosystem products,
+    including FreeRTOS+Trace - an indispensable productivity tool, a DOS
+    compatible FAT file system, and our tiny thread aware UDP/IP stack.
+
+    http://www.OpenRTOS.com - Real Time Engineers ltd license FreeRTOS to High
+    Integrity Systems to sell under the OpenRTOS brand.  Low cost OpenRTOS
+    licenses offer ticketed support, indemnification and middleware.
+
+    http://www.SafeRTOS.com - High Integrity Systems also provide a safety
+    engineered and independently SIL3 certified version for use in safety and
+    mission critical applications that require provable dependability.
+
+    1 tab == 4 spaces!
+*/
+
+/* Standard includes. */
+#include <stdlib.h>
+
+/* Defining MPU_WRAPPERS_INCLUDED_FROM_API_FILE prevents task.h from redefining
+all the API functions to use the MPU wrappers.  That should only be done when
+task.h is included from an application file. */
+#define MPU_WRAPPERS_INCLUDED_FROM_API_FILE
+
+/* FreeRTOS includes. */
+#include "FreeRTOS.h"
+#include "task.h"
+#include "timers.h"
+#include "event_groups.h"
+
+/* Lint e961 and e750 are suppressed as a MISRA exception justified because the
+MPU ports require MPU_WRAPPERS_INCLUDED_FROM_API_FILE to be defined for the
+header files above, but not in this file, in order to generate the correct
+privileged Vs unprivileged linkage and placement. */
+#undef MPU_WRAPPERS_INCLUDED_FROM_API_FILE /*lint !e961 !e750. */
+
+#if ( INCLUDE_xEventGroupSetBitFromISR == 1 ) && ( configUSE_TIMERS == 0 )
+	#error configUSE_TIMERS must be set to 1 to make the xEventGroupSetBitFromISR() function available.
+#endif
+
+#if ( INCLUDE_xEventGroupSetBitFromISR == 1 ) && ( INCLUDE_xTimerPendCallbackFromISR == 0 )
+	#error INCLUDE_xTimerPendCallbackFromISR must also be set to one to make the xEventGroupSetBitFromISR() function available.
+#endif
+
+
+#if configUSE_16_BIT_TICKS == 1
+	#define taskCLEAR_EVENTS_ON_EXIT_BIT		0x0100U
+	#define taskUNBLOCKED_DUE_TO_BIT_SET_BIT	0x0200U
+	#define taskWAIT_FOR_ALL_BITS				0x0400U
+	#define taskEVENT_BITS_CONTROL_BYTES		0xff00U
+#else
+	#define taskCLEAR_EVENTS_ON_EXIT_BIT		0x01000000UL
+	#define taskUNBLOCKED_DUE_TO_BIT_SET_BIT	0x02000000UL
+	#define taskWAIT_FOR_ALL_BITS				0x04000000UL
+	#define taskEVENT_BITS_CONTROL_BYTES		0xff000000UL
+#endif
+
+typedef struct EventBitsDefinition
+{
+	xEventBitsType uxEventBits;
+	xList xTasksWaitingForBits;		/*< List of tasks waiting for a bit to be set. */
+} xEVENT_BITS;
+
+/* Used internally only. */
+typedef struct EVENT_GROUP_CALLBACK_PARAMTERS
+{
+	xEventGroupHandle xTargetEventGroup;
+	xEventBitsType xBitsToSet;
+} xEventGroupCallbackParameters;
+
+/*-----------------------------------------------------------*/
+
+xEventGroupHandle xEventGroupCreate( void )
+{
+xEVENT_BITS *pxEventBits;
+
+	pxEventBits = pvPortMalloc( sizeof( xEVENT_BITS ) );
+	if( pxEventBits != NULL )
+	{
+		pxEventBits->uxEventBits = 0;
+		vListInitialise( &( pxEventBits->xTasksWaitingForBits ) );
+	}
+
+	return ( xEventGroupHandle ) pxEventBits;
+}
+/*-----------------------------------------------------------*/
+
+xEventBitsType xEventGroupSync( xEventGroupHandle xEventGroup, xEventBitsType uxBitsToSet, xEventBitsType uxBitsToWaitFor, portTickType xBlockTime )
+{
+xEventBitsType uxOriginalBitValue, uxReturn;
+xEVENT_BITS *pxEventBits = ( xEVENT_BITS * ) xEventGroup;
+portBASE_TYPE xYieldedAlready;
+
+	vTaskSuspendAll();
+	{
+		uxOriginalBitValue = pxEventBits->uxEventBits;
+
+		( void ) xEventGroupSetBits( xEventGroup, uxBitsToSet );
+
+		if( ( ( uxOriginalBitValue | uxBitsToSet ) & uxBitsToWaitFor ) == uxBitsToWaitFor )
+		{
+			/* All the rendezvous bits will have been set once this task set
+			its bits - no need to block. */
+			uxReturn = ( uxOriginalBitValue | uxBitsToSet );
+
+			/* Rendezvous always clear the bits.  They will have been cleared
+			already unless this is the only task in the rendezvous. */
+			pxEventBits->uxEventBits &= uxBitsToWaitFor;
+
+			xBlockTime = 0;
+		}
+		else
+		{
+			if( xBlockTime != ( portTickType ) 0 )
+			{
+				/* Store the bits that the calling task is waiting for in the
+				task's event list item so the kernel knows when a match is
+				found.  Then enter the blocked state. */
+				vTaskPlaceOnUnorderedEventList( &( pxEventBits->xTasksWaitingForBits ), ( uxBitsToWaitFor | taskCLEAR_EVENTS_ON_EXIT_BIT | taskWAIT_FOR_ALL_BITS ), xBlockTime );
+			}
+			else
+			{
+				/* The rendezvous bits were not set, but no block time was
+				specified - just return the current event bit value. */
+				uxReturn = pxEventBits->uxEventBits;
+			}
+		}
+	}
+	xYieldedAlready = xTaskResumeAll();
+
+	if( xBlockTime != ( portTickType ) 0 )
+	{
+		if( xYieldedAlready == pdFALSE )
+		{
+			portYIELD_WITHIN_API();
+		}
+
+		/* The task blocked to wait for its required bits to be set - at this
+		point either the required bits were set or the block time expired.  If
+		the required bits were set they will have been stored in the task's
+		event list item, and they should now be retrieved then cleared. */
+		uxReturn = uxTaskResetEventItemValue();
+
+		if( ( uxReturn & taskUNBLOCKED_DUE_TO_BIT_SET_BIT ) == ( xEventBitsType ) 0 )
+		{
+			/* The task timed out, just return the current event bit value. */
+			uxReturn = pxEventBits->uxEventBits;
+		}
+		else
+		{
+			/* The task unblocked because the bits were set.  Clear the control
+			bits before returning the value. */
+			uxReturn &= ~taskEVENT_BITS_CONTROL_BYTES;
+		}
+	}
+
+	return uxReturn;
+}
+/*-----------------------------------------------------------*/
+
+xEventBitsType xEventGroupWaitBits( xEventGroupHandle xEventGroup, xEventBitsType uxBitsToWaitFor, portBASE_TYPE xClearOnExit, portBASE_TYPE xWaitForAllBits, portTickType xBlockTime )
+{
+xEVENT_BITS *pxEventBits = ( xEVENT_BITS * ) xEventGroup;
+const xEventBitsType uxCurrentEventBits = pxEventBits->uxEventBits;
+xEventBitsType uxReturn, uxControlBits = 0;
+
+	/* Check the user is not attempting to wait on the bits used by the kernel
+	itself, and that at least one bit is being requested. */
+	configASSERT( ( uxBitsToWaitFor & taskEVENT_BITS_CONTROL_BYTES ) == 0 );
+	configASSERT( uxBitsToWaitFor != 0 );
+
+	taskENTER_CRITICAL();
+	{
+		if( xWaitForAllBits == pdFALSE )
+		{
+			/* Task only has to wait for one bit within uxBitsToWaitFor to be set.  Is
+			one already set? */
+			if( ( uxCurrentEventBits & uxBitsToWaitFor ) != ( xEventBitsType ) 0 )
+			{
+				/* At least one of the bits was set.  No need to block. */
+				xBlockTime = 0;
+			}
+		}
+		else
+		{
+			/* Task has to wait for all the bits in uxBitsToWaitFor to be set.  Are they
+			set already? */
+			if( ( uxCurrentEventBits & uxBitsToWaitFor ) == uxBitsToWaitFor )
+			{
+				/* All the bits were set, no need to block. */
+				xBlockTime = 0;
+			}
+		}
+
+		/* The task can return now if either its wait condition is already met
+		or the requested block time is 0. */
+		if( xBlockTime == ( portTickType ) 0 )
+		{
+			/* No need to block, just set the return value. */
+			uxReturn = uxCurrentEventBits;
+
+			if( xClearOnExit != pdFALSE )
+			{
+				/* The user requested the bits be cleared again prior to exiting
+				this function. */
+				pxEventBits->uxEventBits &= ~uxBitsToWaitFor;
+			}
+		}
+		else
+		{
+			/* The task is going to block to wait for its required bits to be
+			set.  uxControlBits are used to remember the specified behaviour of
+			this call to xEventGroupWaitBits() - for use when the event bits
+			unblock the task. */
+			if( xClearOnExit != pdFALSE )
+			{
+				uxControlBits |= taskCLEAR_EVENTS_ON_EXIT_BIT;
+			}
+
+			if( xWaitForAllBits != pdFALSE )
+			{
+				uxControlBits |= taskWAIT_FOR_ALL_BITS;
+			}
+
+			/* Store the bits that the calling task is waiting for in the
+			task's event list item so the kernel knows when a match is
+			found.  Then enter the blocked state. */
+			vTaskPlaceOnUnorderedEventList( &( pxEventBits->xTasksWaitingForBits ), ( uxBitsToWaitFor | uxControlBits ), xBlockTime );
+			portYIELD_WITHIN_API();
+		}
+	}
+	taskEXIT_CRITICAL();
+
+	if( xBlockTime != ( portTickType ) 0 )
+	{
+		/* The task blocked to wait for its required bits to be set - at this
+		point either the required bits were set or the block time expired.  If
+		the required bits were set they will have been stored in the task's
+		event list item, and they should now be retrieved then cleared. */
+		uxReturn = uxTaskResetEventItemValue();
+
+		if( ( uxReturn & taskUNBLOCKED_DUE_TO_BIT_SET_BIT ) == ( xEventBitsType ) 0 )
+		{
+			/* The task timed out, just return the current event bit value. */
+			uxReturn = pxEventBits->uxEventBits;
+		}
+		else
+		{
+			/* The task unblocked because the bits were set.  Clear the control
+			bits before returning the value. */
+			uxReturn &= ~taskEVENT_BITS_CONTROL_BYTES;
+		}
+	}
+
+	return uxReturn;
+}
+/*-----------------------------------------------------------*/
+
+xEventBitsType xEventGroupClearBits( xEventGroupHandle xEventGroup, xEventBitsType uxBitsToClear )
+{
+xEVENT_BITS *pxEventBits = ( xEVENT_BITS * ) xEventGroup;
+xEventBitsType uxReturn;
+
+	/* Check the user is not attempting to clear the bits used by the kernel
+	itself. */
+	configASSERT( ( uxBitsToClear & taskEVENT_BITS_CONTROL_BYTES ) == 0 );
+
+	uxBitsToClear = ~uxBitsToClear;
+	taskENTER_CRITICAL();
+	{
+		/* The value returned is the event group value prior to the bits being
+		cleared. */
+		uxReturn = pxEventBits->uxEventBits;
+
+		/* Clear the bits. */
+		pxEventBits->uxEventBits &= uxBitsToClear;
+	}
+	taskEXIT_CRITICAL();
+
+	return uxReturn;
+}
+/*-----------------------------------------------------------*/
+
+xEventBitsType xEventGroupSetBits( xEventGroupHandle xEventGroup, xEventBitsType uxBitsToSet )
+{
+xListItem *pxListItem, *pxNext;
+xListItem const *pxListEnd;
+xList *pxList;
+xEventBitsType uxBitsToClear = 0, uxBitsWaitedFor, uxControlBits;
+xEVENT_BITS *pxEventBits = ( xEVENT_BITS * ) xEventGroup;
+portBASE_TYPE xMatchFound = pdFALSE;
+
+	/* Check the user is not attempting to set the bits used by the kernel
+	itself. */
+	configASSERT( ( uxBitsToSet & taskEVENT_BITS_CONTROL_BYTES ) == 0 );
+
+	pxList = &( pxEventBits->xTasksWaitingForBits );
+	pxListEnd = listGET_END_MARKER( pxList ); /*lint !e826 !e740 The mini list structure is used as the list end to save RAM.  This is checked and valid. */
+	pxListItem = listGET_HEAD_ENTRY( pxList );
+	vTaskSuspendAll();
+	{
+		/* Set the bits. */
+		pxEventBits->uxEventBits |= uxBitsToSet;
+
+		/* See if the new bit value should unblock any tasks. */
+		while( pxListItem != pxListEnd )
+		{
+			pxNext = listGET_NEXT( pxListItem );
+			uxBitsWaitedFor = listGET_LIST_ITEM_VALUE( pxListItem );
+
+			/* Split the bits waited for from the control bits. */
+			uxControlBits = uxBitsWaitedFor & taskEVENT_BITS_CONTROL_BYTES;
+			uxBitsWaitedFor &= ~taskEVENT_BITS_CONTROL_BYTES;
+
+			if( ( uxControlBits & taskWAIT_FOR_ALL_BITS ) == ( xEventBitsType ) 0 )
+			{
+				/* Just looking for single bit being set. */
+				if( ( uxBitsWaitedFor & pxEventBits->uxEventBits ) != ( xEventBitsType ) 0 )
+				{
+					xMatchFound = pdTRUE;
+				}
+			}
+			else if( ( uxBitsWaitedFor & pxEventBits->uxEventBits ) == uxBitsWaitedFor )
+			{
+				/* All bits are set. */
+				xMatchFound = pdTRUE;
+			}
+			else
+			{
+				/* Need all bits to be set, but not all the bits were set. */
+			}
+
+			if( xMatchFound != pdFALSE )
+			{
+				/* The bits match.  Should the bits be cleared on exit? */
+				if( ( uxControlBits & taskCLEAR_EVENTS_ON_EXIT_BIT ) != ( xEventBitsType ) 0 )
+				{
+					uxBitsToClear |= uxBitsWaitedFor;
+				}
+
+				/* Store the actual event flag value in the task's event list
+				item before removing the task from the event list.  The
+				taskUNBLOCKED_DUE_TO_BIT_SET_BIT bit is set so the task knows
+				that is was unblocked due to its required bits matching, rather
+				than because it timed out. */
+				( void ) xTaskRemoveFromUnorderedEventList( pxListItem, pxEventBits->uxEventBits | taskUNBLOCKED_DUE_TO_BIT_SET_BIT );
+			}
+
+			/* Move onto the next list item.  Note pxListItem->pxNext is not
+			used here as the list item may have been removed from the event list
+			and inserted into the ready/pending reading list. */
+			pxListItem = pxNext;
+		}
+
+		/* Clear any bits that matched when the taskCLEAR_EVENTS_ON_EXIT_BIT
+		bit was set in the control word. */
+		pxEventBits->uxEventBits &= ~uxBitsToClear;
+	}
+	( void ) xTaskResumeAll();
+
+	return pxEventBits->uxEventBits;
+}
+/*-----------------------------------------------------------*/
+
+void vEventGroupDelete( xEventGroupHandle xEventGroup )
+{
+xEVENT_BITS *pxEventBits = ( xEVENT_BITS * ) xEventGroup;
+const xList *pxTasksWaitingForBits = &( pxEventBits->xTasksWaitingForBits );
+
+	vTaskSuspendAll();
+	{
+		while( listCURRENT_LIST_LENGTH( pxTasksWaitingForBits ) > ( unsigned portBASE_TYPE ) 0 )
+		{
+			/* Unblock the task, returning 0 as the event list is being deleted
+			and	cannot therefore have any bits set. */
+			configASSERT( pxTasksWaitingForBits->xListEnd.pxNext != ( xListItem * ) &( pxTasksWaitingForBits->xListEnd ) );
+			( void ) xTaskRemoveFromUnorderedEventList( pxTasksWaitingForBits->xListEnd.pxNext, ( portTickType ) 0 );
+		}
+
+		vPortFree( pxEventBits );
+	}
+	( void ) xTaskResumeAll();
+}
+/*-----------------------------------------------------------*/
+
+/* For internal use only - execute a 'set bits' command that was pended from
+an interrupt. */
+void vEventGroupSetBitsCallback( void *pvEventGroup, unsigned long ulBitsToSet )
+{
+	( void ) xEventGroupSetBits( pvEventGroup, ( xEventBitsType ) ulBitsToSet );
+}
+
+
diff --git a/FreeRTOS/Source/include/FreeRTOS.h b/FreeRTOS/Source/include/FreeRTOS.h
index 5956500cc..f8e68f86f 100644
--- a/FreeRTOS/Source/include/FreeRTOS.h
+++ b/FreeRTOS/Source/include/FreeRTOS.h
@@ -92,9 +92,10 @@ is included as it is used by the port layer. */
 conform. */
 typedef portBASE_TYPE (*pdTASK_HOOK_CODE)( void * );
 
-
-
-
+/* The type that holds event bits always matches portTickType - therefore the
+number of bits it holds is set by configUSE_16_BIT_TICKS (16 bits if set to 1,
+32 bits if set to 0. */
+typedef portTickType xEventBitsType;
 
 /*
  * Check all the required application specific macros have been defined.
@@ -190,6 +191,10 @@ typedef portBASE_TYPE (*pdTASK_HOOK_CODE)( void * );
 	#define configUSE_TIMERS 0
 #endif
 
+#ifndef configUSE_EVENT_GROUPS
+	#define configUSE_EVENT_GROUPS 0
+#endif
+
 #ifndef configUSE_COUNTING_SEMAPHORES
 	#define configUSE_COUNTING_SEMAPHORES 0
 #endif
@@ -218,6 +223,14 @@ typedef portBASE_TYPE (*pdTASK_HOOK_CODE)( void * );
 	#define INCLUDE_xTaskResumeFromISR 1
 #endif
 
+#ifndef INCLUDE_xEventGroupSetBitFromISR
+	#define INCLUDE_xEventGroupSetBitFromISR 0
+#endif
+
+#ifndef INCLUDE_xTimerPendCallbackFromISR
+	#define INCLUDE_xTimerPendCallbackFromISR 0
+#endif
+
 #ifndef configASSERT
 	#define configASSERT( x )
 	#define configASSERT_DEFINED 0
diff --git a/FreeRTOS/Source/include/event_groups.h b/FreeRTOS/Source/include/event_groups.h
new file mode 100644
index 000000000..36a4c85b3
--- /dev/null
+++ b/FreeRTOS/Source/include/event_groups.h
@@ -0,0 +1,625 @@
+/*
+    FreeRTOS V7.6.0 - Copyright (C) 2013 Real Time Engineers Ltd.
+    All rights reserved
+
+    VISIT http://www.FreeRTOS.org TO ENSURE YOU ARE USING THE LATEST VERSION.
+
+    ***************************************************************************
+     *                                                                       *
+     *    FreeRTOS provides completely free yet professionally developed,    *
+     *    robust, strictly quality controlled, supported, and cross          *
+     *    platform software that has become a de facto standard.             *
+     *                                                                       *
+     *    Help yourself get started quickly and support the FreeRTOS         *
+     *    project by purchasing a FreeRTOS tutorial book, reference          *
+     *    manual, or both from: http://www.FreeRTOS.org/Documentation        *
+     *                                                                       *
+     *    Thank you!                                                         *
+     *                                                                       *
+    ***************************************************************************
+
+    This file is part of the FreeRTOS distribution.
+
+    FreeRTOS is free software; you can redistribute it and/or modify it under
+    the terms of the GNU General Public License (version 2) as published by the
+    Free Software Foundation >>!AND MODIFIED BY!<< the FreeRTOS exception.
+
+    >>! NOTE: The modification to the GPL is included to allow you to distribute
+    >>! a combined work that includes FreeRTOS without being obliged to provide
+    >>! the source code for proprietary components outside of the FreeRTOS
+    >>! kernel.
+
+    FreeRTOS is distributed in the hope that it will be useful, but WITHOUT ANY
+    WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+    FOR A PARTICULAR PURPOSE.  Full license text is available from the following
+    link: http://www.freertos.org/a00114.html
+
+    1 tab == 4 spaces!
+
+    ***************************************************************************
+     *                                                                       *
+     *    Having a problem?  Start by reading the FAQ "My application does   *
+     *    not run, what could be wrong?"                                     *
+     *                                                                       *
+     *    http://www.FreeRTOS.org/FAQHelp.html                               *
+     *                                                                       *
+    ***************************************************************************
+
+    http://www.FreeRTOS.org - Documentation, books, training, latest versions,
+    license and Real Time Engineers Ltd. contact details.
+
+    http://www.FreeRTOS.org/plus - A selection of FreeRTOS ecosystem products,
+    including FreeRTOS+Trace - an indispensable productivity tool, a DOS
+    compatible FAT file system, and our tiny thread aware UDP/IP stack.
+
+    http://www.OpenRTOS.com - Real Time Engineers ltd license FreeRTOS to High
+    Integrity Systems to sell under the OpenRTOS brand.  Low cost OpenRTOS
+    licenses offer ticketed support, indemnification and middleware.
+
+    http://www.SafeRTOS.com - High Integrity Systems also provide a safety
+    engineered and independently SIL3 certified version for use in safety and
+    mission critical applications that require provable dependability.
+
+    1 tab == 4 spaces!
+*/
+
+#ifndef EVENT_GROUPS_H
+#define EVENT_GROUPS_H
+
+#ifndef INC_FREERTOS_H
+	#error "include FreeRTOS.h" must appear in source files before "include event_groups.h"
+#endif
+
+#include "timers.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * An event group is a collection of bits to which an application can assign a
+ * meaning.  For example, an application may create an event group to convey
+ * the status of various CAN bus related events in which bit 0 might mean "A CAN
+ * message has been received and is ready for processing", bit 1 might mean "The
+ * application has queued a message that is ready for sending onto the CAN
+ * network", and bit 2 might mean "it is time to send a SYNC message onto the
+ * CAN network" etc.  A task can then test the bit values to see which events
+ * are active, and optionally enter the Blocked state to wait for a specified
+ * bit or a group of specified bits to be active.  To continue the CAN bus
+ * example, a CAN controlling task can enter the Blocked state (and therefore
+ * not consume any processing time) until either bit 0, bit 1 or bit 2 are
+ * active, at which time the bit that was actually active would inform the task
+ * which action it had to take (process a received message, send a message, or
+ * send a SYNC).
+ *
+ * The event groups implementation contains intelligence to avoid race
+ * conditions that would otherwise occur were an application to use a simple
+ * variable for the same purpose.  This is particularly important with respect
+ * to when a bit within an event group is to be cleared, and when bits have to
+ * be set and then tested atomically - as is the case where event groups are
+ * used to create a synchronisation point between multiple tasks (a
+ * 'rendezvous').
+ *
+ * \defgroup EventGroup
+ */
+
+
+
+/**
+ * event_groups.h
+ *
+ * Type by which event groups are referenced.  For example, a call to
+ * xEventGroupCreate() returns an xEventGroupHandle variable that can then
+ * be used as a parameter to other event group functions.
+ *
+ * \defgroup xEventGroupHandle xEventGroupHandle
+ * \ingroup EventGroup
+ */
+typedef void * xEventGroupHandle;
+
+/**
+ * event_groups.h
+ *<pre>
+ xEventGroupHandle xEventGroupCreate( void );
+ </pre>
+ *
+ * Create a new event group.  This function cannot be called from an interrupt.
+ *
+ * Although event groups are not related to ticks, for internal implementation
+ * reasons the number of bits available for use in an event group is dependent
+ * on the configUSE_16_BIT_TICKS setting in FreeRTOSConfig.h.  If
+ * configUSE_16_BIT_TICKS is 1 then each event group contains 8 usable bits (bit
+ * 0 to bit 7).  If configUSE_16_BIT_TICKS is set to 0 then each event group has
+ * 24 usable bits (bit 0 to bit 23).  The xEventBitsType type is used to store
+ * event bits within an event group.
+ *
+ * @return If the event group was created then a handle to the event group is
+ * returned.  If there was insufficient FreeRTOS heap available to create the
+ * event group then NULL is returned.  See http://www.freertos.org/a00111.html
+ *
+ * Example usage:
+   <pre>
+	// Declare a variable to hold the created event group.
+	xEventGroupHandle xCreatedEventGroup;
+
+	// Attempt to create the event group.
+	xCreatedEventGroup = xEventGroupCreate();
+
+	// Was the event group created successfully?
+	if( xCreatedEventGroup == NULL )
+	{
+		// The event group was not created because there was insufficient
+		// FreeRTOS heap available.
+	}
+	else
+	{
+		// The event group was created.
+	}
+   </pre>
+ * \defgroup xEventGroupCreate xEventGroupCreate
+ * \ingroup EventGroup
+ */
+xEventGroupHandle xEventGroupCreate( void ) PRIVILEGED_FUNCTION;
+
+/**
+ * event_groups.h
+ *<pre>
+	xEventBitsType xEventGroupWaitBits( xEventGroupHandle xEventGroup,
+										xEventBitsType uxBitsToWaitFor,
+										portBASE_TYPE xClearOnExit,
+										portBASE_TYPE xWaitForAllBits,
+										portTickType xBlockTime );
+ </pre>
+ *
+ * [Potentially] block to wait for one or more bits to be set within a
+ * previously created event group.
+ *
+ * This function cannot be called from an interrupt.
+ *
+ * @param xEventGroup The event group in which the bits are being tested.  The
+ * event group must have previously been created using a call to
+ * xEventGroupCreate().
+ *
+ * @param uxBitsToWaitFor A bitwise value that indicates the bit or bits to test
+ * inside the event group.  For example, to wait for bit 0 and/or bit 2 set
+ * uxBitsToWaitFor to 0x05.  To wait for bits 0 and/or bit 1 and/or bit 2 set
+ * uxBitsToWaitFor to 0x07.  Etc.
+ *
+ * @param xClearOnExit If xClearOnExit is set to pdTRUE then any bits within
+ * uxBitsToWaitFor that are set within the event group will be cleared before
+ * xEventGroupWaitBits() returns.  If xClearOnExit is set to pdFALSE then the
+ * bits set in the event group are not altered when the call to
+ * xEventGroupWaitBits() returns.
+ *
+ * @param xWaitForAllBits If xWaitForAllBits is set to pdTRUE then
+ * xEventGroupWaitBits() will return when either all the bits in uxBitsToWaitFor
+ * are set or the specified block time expires.  If xWaitForAllBits is set to
+ * pdFALSE then xEventGroupWaitBits() will return when any one of the bits set
+ * in uxBitsToWaitFor is set or the specified block time expires.
+ *
+ * @param xBlockTime The maximum amount of time (specified in 'ticks') to wait
+ * for one/all (depending on the xWaitForAllBits value) of the bits specified by
+ * uxBitsToWaitFor to become set.
+ *
+ * @return The value of the event group at the time either the bits being waited
+ * for became set, or the block time expired.  Test the return value to know
+ * which bits were set.  If xEventGroupWaitBits() returned because its timeout
+ * expired then not all the bits being waited for will be set.  If
+ * xEventGroupWaitBits() returned because the bits it was waiting for were set
+ * then the returned value is the event group value before any bits were
+ * automatically cleared because the xClearOnExit parameter was set to pdTRUE.
+ *
+ * Example usage:
+   <pre>
+   #define BIT_0	( 1 << 0 )
+   #define BIT_4	( 1 << 4 )
+
+   void aFunction( xEventGroupHandle xEventGroup )
+   {
+   xEventBitsType uxBits;
+   const portTickType xBlockTime = 100 / portTICK_RATE_MS;
+
+		// Wait a maximum of 100ms for either bit 0 or bit 4 to be set within
+		// the event group.  Clear the bits before exiting.
+		uxBits = xEventGroupWaitBits(
+					xEventGroup,	// The event group being tested.
+					BIT_0 | BIT_4,	// The bits within the event group to wait for.
+					pdTRUE,			// BIT_0 and BIT_4 should be cleared before returning.
+					pdFALSE,		// Don't wait for both bits, either bit will do.
+					xBlockTime );	// Wait a maximum of 100ms for either bit to be set.
+
+		if( ( uxBits & ( BIT_0 | BIT_4 ) ) == ( BIT_0 | BIT_4 ) )
+		{
+			// xEventGroupWaitBits() returned because both bits were set.
+		}
+		else if( ( uxBits & BIT_0 ) != 0 )
+		{
+			// xEventGroupWaitBits() returned because just BIT_0 was set.
+		}
+		else if( ( uxBits & BIT_4 ) != 0 )
+		{
+			// xEventGroupWaitBits() returned because just BIT_4 was set.
+		}
+		else
+		{
+			// xEventGroupWaitBits() returned because xBlockTime ticks passed
+			// without either BIT_0 or BIT_4 becoming set.
+		}
+   }
+   </pre>
+ * \defgroup xEventGroupWaitBits xEventGroupWaitBits
+ * \ingroup EventGroup
+ */
+xEventBitsType xEventGroupWaitBits( xEventGroupHandle xEventGroup, xEventBitsType uxBitsToWaitFor, portBASE_TYPE xClearOnExit, portBASE_TYPE xWaitForAllBits, portTickType xBlockTime ) PRIVILEGED_FUNCTION;
+
+/**
+ * event_groups.h
+ *<pre>
+	xEventBitsType xEventGroupClearBits( xEventGroupHandle xEventGroup, xEventBitsType uxBitsToClear );
+ </pre>
+ *
+ * Clear bits within an event group.  This function cannot be called from an
+ * interrupt.
+ *
+ * @param xEventGroup The event group in which the bits are to be cleared.
+ *
+ * @param uxBitsToClear A bitwise value that indicates the bit or bits to clear
+ * in the event group.  For example, to clear bit 3 only, set uxBitsToClear to
+ * 0x08.  To clear bit 3 and bit 0 set uxBitsToClear to 0x09.
+ *
+ * @return The value of the event group before the specified bits were cleared.
+ *
+ * Example usage:
+   <pre>
+   #define BIT_0	( 1 << 0 )
+   #define BIT_4	( 1 << 4 )
+
+   void aFunction( xEventGroupHandle xEventGroup )
+   {
+   xEventBitsType uxBits;
+
+		// Clear bit 0 and bit 4 in xEventGroup.
+		uxBits = xEventGroupClearBits(
+								xEventGroup,	// The event group being updated.
+								BIT_0 | BIT_4 );// The bits being cleared.
+
+		if( ( uxBits & ( BIT_0 | BIT_4 ) ) == ( BIT_0 | BIT_4 ) )
+		{
+			// Both bit 0 and bit 4 were set before the call to
+			// xEventGroupClearBits() was called.  Both will now be clear (not
+			// set).
+		}
+		else if( ( uxBits & BIT_0 ) != 0 )
+		{
+			// Bit 0 was set before xEventGroupClearBits() was called.  It will
+			// now be clear.
+		}
+		else if( ( uxBits & BIT_4 ) != 0 )
+		{
+			// Bit 4 was set before xEventGroupClearBits() was called.  It will
+			// now be clear.
+		}
+		else
+		{
+			// Neither bit 0 nor bit 4 were set in the first place.
+		}
+   }
+   </pre>
+ * \defgroup xEventGroupClearBits xEventGroupClearBits
+ * \ingroup EventGroup
+ */
+xEventBitsType xEventGroupClearBits( xEventGroupHandle xEventGroup, xEventBitsType uxBitsToClear ) PRIVILEGED_FUNCTION;
+
+/**
+ * event_groups.h
+ *<pre>
+	xEventBitsType xEventGroupSetBits( xEventGroupHandle xEventGroup, xEventBitsType uxBitsToSet );
+ </pre>
+ *
+ * Set bits within an event group.
+ * This function cannot be called from an interrupt.  xEventGroupSetBitsFromISR()
+ * is a version that can be called from an interrupt.
+ *
+ * Setting bits in an event group will automatically unblock tasks that are
+ * blocked waiting for the bits.
+ *
+ * @param xEventGroup The event group in which the bits are to be set.
+ *
+ * @param uxBitsToSet A bitwise value that indicates the bit or bits to set.
+ * For example, to set bit 3 only, set uxBitsToSet to 0x08.  To set bit 3
+ * and bit 0 set uxBitsToSet to 0x09.
+ *
+ * @return The value of the event group at the time the call to
+ * xEventGroupSetBits() returns.  There are two reasons why the returned value
+ * might have the bits specified by the uxBitsToSet parameter cleared.  First,
+ * if setting a bit results in a task that was waiting for the bit leaving the
+ * blocked state then it is possible the bit will be cleared automatically
+ * (see the xClearBitOnExit parameter of xEventGroupWaitBits()).  Second, any
+ * unblocked (or otherwise Ready state) task that has a priority above that of
+ * the task that called xEventGroupSetBits() will execute and may change the
+ * event group value before the call to xEventGroupSetBits() returns.
+ *
+ * Example usage:
+   <pre>
+   #define BIT_0	( 1 << 0 )
+   #define BIT_4	( 1 << 4 )
+
+   void aFunction( xEventGroupHandle xEventGroup )
+   {
+   xEventBitsType uxBits;
+
+		// Set bit 0 and bit 4 in xEventGroup.
+		uxBits = xEventGroupSetBits(
+							xEventGroup,	// The event group being updated.
+							BIT_0 | BIT_4 );// The bits being set.
+
+		if( ( uxBits & ( BIT_0 | BIT_4 ) ) == ( BIT_0 | BIT_4 ) )
+		{
+			// Both bit 0 and bit 4 remained set when the function returned.
+		}
+		else if( ( uxBits & BIT_0 ) != 0 )
+		{
+			// Bit 0 remained set when the function returned, but bit 4 was
+			// cleared.  It might be that bit 4 was cleared automatically as a
+			// task that was waiting for bit 4 was removed from the Blocked
+			// state.
+		}
+		else if( ( uxBits & BIT_4 ) != 0 )
+		{
+			// Bit 4 remained set when the function returned, but bit 0 was
+			// cleared.  It might be that bit 0 was cleared automatically as a
+			// task that was waiting for bit 0 was removed from the Blocked
+			// state.
+		}
+		else
+		{
+			// Neither bit 0 nor bit 4 remained set.  It might be that a task
+			// was waiting for either or both of the bits to be set, and the
+			// bits were cleared as the task left the Blocked state.
+		}
+   }
+   </pre>
+ * \defgroup xEventGroupSetBits xEventGroupSetBits
+ * \ingroup EventGroup
+ */
+xEventBitsType xEventGroupSetBits( xEventGroupHandle xEventGroup, xEventBitsType uxBitsToSet ) PRIVILEGED_FUNCTION;
+
+/**
+ * event_groups.h
+ *<pre>
+	xEventBitsType xEventGroupSetBitsFromISR( xEventGroupHandle xEventGroup, xEventBitsType uxBitsToSet, portBASE_TYPE *pxHigherPriorityTaskWoken );
+ </pre>
+ *
+ * A version of xEventGroupSetBits() that can be called from an interrupt.
+ *
+ * Setting bits in an event group is not a deterministic operation because there
+ * are an unknown number of tasks that may be waiting for the bit or bits being
+ * set.  FreeRTOS does not allow nondeterministic operations to be performed in
+ * interrupts or from critical sections.  Therefore xEventGroupSetBitFromISR()
+ * sends a message to the timer task to have the set operation performed in the
+ * context of the timer task - where a scheduler lock is used in place of a
+ * critical section.
+ *
+ * @param xEventGroup The event group in which the bits are to be set.
+ *
+ * @param uxBitsToSet A bitwise value that indicates the bit or bits to set.
+ * For example, to set bit 3 only, set uxBitsToSet to 0x08.  To set bit 3
+ * and bit 0 set uxBitsToSet to 0x09.
+ *
+ * @ pxHigherPriorityTaskWoken As mentioned above, calling this function will
+ * result in a message being sent to the timer daemon task.  If the priority of
+ * the timer daemon task is higher than the priority of the currently running
+ * task (the task the interrupt interrupted) then *pxHigherPriorityTaskWoken
+ * will be set to pdTRUE by xEventGroupSetBitsFromISR(), indicating that a
+ * context switch should be requested before the interrupt exits.  For that
+ * reason *pxHigherPriorityTaskWoken must be initialised to pdFALSE.  See the
+ * example code below.
+ *
+ * @return If the callback request was registered successfully then pdPASS is
+ * returned, otherwise pdFALSE is returned.  pdFALSE will be returned if the
+ * timer service queue was full.
+ *
+ * Example usage:
+   <pre>
+   #define BIT_0	( 1 << 0 )
+   #define BIT_4	( 1 << 4 )
+
+   // An event group which it is assume has already been created by a call to
+   // xEventGroupCreate().
+   xEventGroupHandle xEventGroup;
+
+   void anInterruptHandler( void )
+   {
+   portBASE_TYPE xHigherPriorityTaskWoken;
+
+		// xHigherPriorityTaskWoken must be initialised to pdFALSE;
+		xHigherPriorityTaskWoken = pdFALSE;
+
+		// Set bit 0 and bit 4 in xEventGroup.
+		uxBits = xEventGroupSetBitsFromISR(
+							xEventGroup,	// The event group being updated.
+							BIT_0 | BIT_4   // The bits being set.
+							&xHigherPriorityTaskWoken );
+
+		// If xHigherPriorityTaskWoken is now set to pdTRUE then a context
+		// switch should be requested.  The macro used is port specific and will
+		// be either portYIELD_FROM_ISR() or portEND_SWITCHING_ISR() - refer to
+		// the documentation page for the port being used.
+		portYIELD_FROM_ISR( xHigherPriorityTaskWoken );
+   }
+   </pre>
+ * \defgroup xEventGroupSetBitsFromISR xEventGroupSetBitsFromISR
+ * \ingroup EventGroup
+ */
+#define xEventGroupSetBitsFromISR( xEventGroup, uxBitsToSet, pxHigherPriorityTaskWoken ) xTimerPendCallbackFromISR( vEventGroupSetBitsCallback, ( void * ) xEventGroup, ( unsigned long ) uxBitsToSet, pxHigherPriorityTaskWoken )
+
+/**
+ * event_groups.h
+ *<pre>
+	xEventBitsType xEventGroupSync(	xEventGroupHandle xEventGroup,
+									xEventBitsType uxBitsToSet,
+									xEventBitsType uxBitsToWaitFor,
+									portTickType xBlockTime );
+ </pre>
+ *
+ * Atomically set bits within an event group, then wait for a combination of
+ * bits to be set within the same event group.  This functionality is typically
+ * used to synchronise multiple tasks, where each task has to wait for the other
+ * tasks to reach a synchronisation point before proceeding.
+ *
+ * This function cannot be used from an interrupt.
+ *
+ * The function will return before its block time expires if the bits specified
+ * by the uxBitsToWait parameter are set, or become set within that time.  In
+ * this case all the bits specified by uxBitsToWait will be automatically
+ * cleared before the function returns.
+ *
+ * @param xEventGroup The event group in which the bits are being tested.  The
+ * event group must have previously been created using a call to
+ * xEventGroupCreate().
+ *
+ * @param uxBitsToSet The bits to set in the event group before determining
+ * if, and possibly waiting for, all the bits specified by the uxBitsToWait
+ * parameter are set.
+ *
+ * @param uxBitsToWaitFor A bitwise value that indicates the bit or bits to test
+ * inside the event group.  For example, to wait for bit 0 and bit 2 set
+ * uxBitsToWaitFor to 0x05.  To wait for bits 0 and bit 1 and bit 2 set
+ * uxBitsToWaitFor to 0x07.  Etc.
+ *
+ * @param xBlockTime The maximum amount of time (specified in 'ticks') to wait
+ * for all of the bits specified by uxBitsToWaitFor to become set.
+ *
+ * @return The value of the event group at the time either the bits being waited
+ * for became set, or the block time expired.  Test the return value to know
+ * which bits were set.  If xEventGroupSync() returned because its timeout
+ * expired then not all the bits being waited for will be set.  If
+ * xEventGroupSync() returned because all the bits it was waiting for were
+ * set then the returned value is the event group value before any bits were
+ * automatically cleared.
+ *
+ * Example usage:
+ <pre>
+ // Bits used by the three tasks.
+ #define TASK_0_BIT		( 1 << 0 )
+ #define TASK_1_BIT		( 1 << 1 )
+ #define TASK_2_BIT		( 1 << 2 )
+
+ #define ALL_SYNC_BITS ( TASK_0_BIT | TASK_1_BIT | TASK_2_BIT )
+
+ // Use an event group to synchronise three tasks.  It is assumed this event
+ // group has already been created elsewhere.
+ xEventGroupHandle xEventBits;
+
+ void vTask0( void *pvParameters )
+ {
+ xEventBitsType uxReturn;
+ portTickType xBlockTime = 100 / portTICK_RATE_MS;
+
+	 for( ;; )
+	 {
+		// Perform task functionality here.
+
+		// Set bit 0 in the event flag to note this task has reached the
+		// sync point.  The other two tasks will set the other two bits defined
+		// by ALL_SYNC_BITS.  All three tasks have reached the synchronisation
+		// point when all the ALL_SYNC_BITS are set.  Wait a maximum of 100ms
+		// for this to happen.
+		uxReturn = xEventGroupSync( xEventBits, TASK_0_BIT, ALL_SYNC_BITS, xBlockTime );
+
+		if( ( uxReturn & ALL_SYNC_BITS ) == ALL_SYNC_BITS )
+		{
+			// All three tasks reached the synchronisation point before the call
+			// to xEventGroupSync() timed out.
+		}
+	}
+ }
+
+ void vTask1( void *pvParameters )
+ {
+	 for( ;; )
+	 {
+		// Perform task functionality here.
+
+		// Set bit 1 in the event flag to note this task has reached the
+		// synchronisation point.  The other two tasks will set the other two
+		// bits defined by ALL_SYNC_BITS.  All three tasks have reached the
+		// synchronisation point when all the ALL_SYNC_BITS are set.  Wait
+		// indefinitely for this to happen.
+		xEventGroupSync( xEventBits, TASK_1_BIT, ALL_SYNC_BITS, portMAX_DELAY );
+
+		// xEventGroupSync() was called with an indefinite block time, so
+		// this task will only reach here if the syncrhonisation was made by all
+		// three tasks, so there is no need to test the return value.
+	 }
+ }
+
+ void vTask2( void *pvParameters )
+ {
+	 for( ;; )
+	 {
+		// Perform task functionality here.
+
+		// Set bit 2 in the event flag to note this task has reached the
+		// synchronisation point.  The other two tasks will set the other two
+		// bits defined by ALL_SYNC_BITS.  All three tasks have reached the
+		// synchronisation point when all the ALL_SYNC_BITS are set.  Wait
+		// indefinitely for this to happen.
+		xEventGroupSync( xEventBits, TASK_2_BIT, ALL_SYNC_BITS, portMAX_DELAY );
+
+		// xEventGroupSync() was called with an indefinite block time, so
+		// this task will only reach here if the syncrhonisation was made by all
+		// three tasks, so there is no need to test the return value.
+	}
+ }
+
+ </pre>
+ * \defgroup xEventGroupSync xEventGroupSync
+ * \ingroup EventGroup
+ */
+xEventBitsType xEventGroupSync( xEventGroupHandle xEventGroup, xEventBitsType uxBitsToSet, xEventBitsType uxBitsToWaitFor, portTickType xBlockTime ) PRIVILEGED_FUNCTION;
+
+
+/**
+ * event_groups.h
+ *<pre>
+	xEventBitsType xEventGroupGetBits( xEventGroupHandle xEventGroup );
+ </pre>
+ *
+ * Returns the current value of the bits in an event group.  This function
+ * cannot be used from an interrupt.
+ *
+ * @param xEventGroup The event group being queried.
+ *
+ * @return The event group bits at the time xEventGroupGetBits() was called.
+ *
+ * \defgroup xEventGroupGetBits xEventGroupGetBits
+ * \ingroup EventGroup
+ */
+#define xEventGroupGetBits( xEventGroup ) xEventGroupClearBits( xEventGroup, 0 )
+
+/**
+ * event_groups.h
+ *<pre>
+	void xEventGroupDelete( xEventGroupHandle xEventGroup );
+ </pre>
+ *
+ * Delete an event group that was previously created by a call to
+ * xEventGroupCreate().  Tasks that are blocked on the event group will be
+ * unblocked and obtain 0 as the event group's value.
+ *
+ * @param xEventGroup The event group being deleted.
+ */
+void vEventGroupDelete( xEventGroupHandle xEventGroup );
+
+/* For internal use only. */
+void vEventGroupSetBitsCallback( void *pvEventGroup, unsigned long ulBitsToSet );
+
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* EVENT_GROUPS_H */
+
+
diff --git a/FreeRTOS/Source/include/list.h b/FreeRTOS/Source/include/list.h
index cc70e0689..a49368893 100644
--- a/FreeRTOS/Source/include/list.h
+++ b/FreeRTOS/Source/include/list.h
@@ -205,7 +205,31 @@ typedef struct xLIST
  * \page listGET_LIST_ITEM_VALUE listGET_LIST_ITEM_VALUE
  * \ingroup LinkedList
  */
-#define listGET_ITEM_VALUE_OF_HEAD_ENTRY( pxList )			( (&( ( pxList )->xListEnd ))->pxNext->xItemValue )
+#define listGET_ITEM_VALUE_OF_HEAD_ENTRY( pxList )			( ( ( pxList )->xListEnd ).pxNext->xItemValue )
+
+/*
+ * Return the list item at the head of the list.
+ *
+ * \page listGET_HEAD_ENTRY listGET_HEAD_ENTRY
+ * \ingroup LinkedList
+ */
+#define listGET_HEAD_ENTRY( pxList )						( ( ( pxList )->xListEnd ).pxNext )
+
+/*
+ * Return the list item at the head of the list.
+ *
+ * \page listGET_HEAD_ENTRY listGET_HEAD_ENTRY
+ * \ingroup LinkedList
+ */
+#define listGET_NEXT( pxListItem )							( ( pxListItem )->pxNext )
+
+/*
+ * Return the list item that marks the end of the list
+ *
+ * \page listGET_END_MARKER listGET_END_MARKER
+ * \ingroup LinkedList
+ */
+#define listGET_END_MARKER( pxList )						( ( xListItem const * ) ( &( ( pxList )->xListEnd ) ) )
 
 /*
  * Access macro to determine if a list contains any items.  The macro will
diff --git a/FreeRTOS/Source/include/portable.h b/FreeRTOS/Source/include/portable.h
index 1240ecf60..9af5eb27d 100644
--- a/FreeRTOS/Source/include/portable.h
+++ b/FreeRTOS/Source/include/portable.h
@@ -368,6 +368,7 @@ void *pvPortMalloc( size_t xSize ) PRIVILEGED_FUNCTION;
 void vPortFree( void *pv ) PRIVILEGED_FUNCTION;
 void vPortInitialiseBlocks( void ) PRIVILEGED_FUNCTION;
 size_t xPortGetFreeHeapSize( void ) PRIVILEGED_FUNCTION;
+size_t xPortGetMinimumEverFreeHeapSize( void ) PRIVILEGED_FUNCTION;
 
 /*
  * Setup the hardware ready for the scheduler to take control.  This generally
diff --git a/FreeRTOS/Source/include/projdefs.h b/FreeRTOS/Source/include/projdefs.h
index f292a0854..74aa84f0d 100644
--- a/FreeRTOS/Source/include/projdefs.h
+++ b/FreeRTOS/Source/include/projdefs.h
@@ -1,5 +1,5 @@
 /*
-    FreeRTOS V7.6.0 - Copyright (C) 2013 Real Time Engineers Ltd. 
+    FreeRTOS V7.6.0 - Copyright (C) 2013 Real Time Engineers Ltd.
     All rights reserved
 
     VISIT http://www.FreeRTOS.org TO ENSURE YOU ARE USING THE LATEST VERSION.
@@ -69,6 +69,10 @@
 /* Defines the prototype to which task functions must conform. */
 typedef void (*pdTASK_CODE)( void * );
 
+/* Defines the prototype to which callback functions called from the RTOS/timer
+daemon task must conform. */
+typedef void (*pdAPPLICATION_CALLBACK_CODE)( void *, unsigned long );
+
 #define pdFALSE		( ( portBASE_TYPE ) 0 )
 #define pdTRUE		( ( portBASE_TYPE ) 1 )
 
diff --git a/FreeRTOS/Source/include/task.h b/FreeRTOS/Source/include/task.h
index ba7b32d7b..d7330a974 100644
--- a/FreeRTOS/Source/include/task.h
+++ b/FreeRTOS/Source/include/task.h
@@ -1378,15 +1378,26 @@ portBASE_TYPE xTaskIncrementTick( void ) PRIVILEGED_FUNCTION;
  * there be no higher priority tasks waiting on the same event) or
  * the delay period expires.
  *
+ * The 'unordered' version replaces the event list item value with the 
+ * xItemValue value, and inserts the list item at the end of the list.
+ *
+ * The 'ordered' version uses the existing event list item value (which is the
+ * owning tasks priority) to insert the list item into the event list is task
+ * priority order.
+ *
  * @param pxEventList The list containing tasks that are blocked waiting
  * for the event to occur.
  *
+ * @param xItemValue The item value to use for the event list item when the
+ * event list is not ordered by task priority.
+ *
  * @param xTicksToWait The maximum amount of time that the task should wait
  * for the event to occur.  This is specified in kernel ticks,the constant
  * portTICK_RATE_MS can be used to convert kernel ticks into a real time
  * period.
  */
 void vTaskPlaceOnEventList( xList * const pxEventList, portTickType xTicksToWait ) PRIVILEGED_FUNCTION;
+void vTaskPlaceOnUnorderedEventList( xList * pxEventList, portTickType xItemValue, portTickType xTicksToWait ) PRIVILEGED_FUNCTION;
 
 /*
  * THIS FUNCTION MUST NOT BE USED FROM APPLICATION CODE.  IT IS AN
@@ -1412,13 +1423,23 @@ void vTaskPlaceOnEventListRestricted( xList * const pxEventList, portTickType xT
  * Removes a task from both the specified event list and the list of blocked
  * tasks, and places it on a ready queue.
  *
- * xTaskRemoveFromEventList () will be called if either an event occurs to
- * unblock a task, or the block timeout period expires.
+ * xTaskRemoveFromEventList()/xTaskRemoveFromUnorderedEventList() will be called 
+ * if either an event occurs to unblock a task, or the block timeout period 
+ * expires.
+ *
+ * xTaskRemoveFromEventList() is used when the event list is in task priority
+ * order.  It removes the list item from the head of the event list as that will
+ * have the highest priority owning task of all the tasks on the event list.
+ * xTaskRemoveFromUnorderedEventList() is used when the event list is not
+ * ordered and the event list items hold something other than the owning tasks
+ * priority.  In this case the event list item value is updated to the value
+ * passed in the xItemValue parameter.
  *
  * @return pdTRUE if the task being removed has a higher priority than the task
  * making the call, otherwise pdFALSE.
  */
 signed portBASE_TYPE xTaskRemoveFromEventList( const xList * const pxEventList ) PRIVILEGED_FUNCTION;
+signed portBASE_TYPE xTaskRemoveFromUnorderedEventList( xListItem * pxEventListItem, portTickType xItemValue ) PRIVILEGED_FUNCTION;
 
 /*
  * THIS FUNCTION MUST NOT BE USED FROM APPLICATION CODE.  IT IS ONLY
@@ -1430,6 +1451,12 @@ signed portBASE_TYPE xTaskRemoveFromEventList( const xList * const pxEventList )
  */
 void vTaskSwitchContext( void ) PRIVILEGED_FUNCTION;
 
+/*
+ * THESE FUNCTIONS MUST NOT BE USED FROM APPLICATION CODE.  THEY ARE USED BY
+ * THE EVENT BITS MODULE.
+ */
+portTickType uxTaskResetEventItemValue( void ) PRIVILEGED_FUNCTION;
+
 /*
  * Return the handle of the calling task.
  */
@@ -1479,13 +1506,13 @@ signed portBASE_TYPE xTaskGenericCreate( pdTASK_CODE pxTaskCode, const signed ch
 /*
  * Get the uxTCBNumber assigned to the task referenced by the xTask parameter.
  */
-unsigned portBASE_TYPE uxTaskGetTaskNumber( xTaskHandle xTask );
+unsigned portBASE_TYPE uxTaskGetTaskNumber( xTaskHandle xTask ) PRIVILEGED_FUNCTION;
 
 /*
  * Set the uxTCBNumber of the task referenced by the xTask parameter to
  * ucHandle.
  */
-void vTaskSetTaskNumber( xTaskHandle xTask, unsigned portBASE_TYPE uxHandle );
+void vTaskSetTaskNumber( xTaskHandle xTask, unsigned portBASE_TYPE uxHandle ) PRIVILEGED_FUNCTION;
 
 /*
  * If tickless mode is being used, or a low power mode is implemented, then
@@ -1494,7 +1521,7 @@ void vTaskSetTaskNumber( xTaskHandle xTask, unsigned portBASE_TYPE uxHandle );
  * to date with the actual execution time by being skipped forward by the by
  * a time equal to the idle period.
  */
-void vTaskStepTick( portTickType xTicksToJump );
+void vTaskStepTick( portTickType xTicksToJump ) PRIVILEGED_FUNCTION;
 
 /*
  * Provided for use within portSUPPRESS_TICKS_AND_SLEEP() to allow the port
@@ -1509,7 +1536,7 @@ void vTaskStepTick( portTickType xTicksToJump );
  * critical section between the timer being stopped and the sleep mode being
  * entered to ensure it is ok to proceed into the sleep mode.
  */
-eSleepModeStatus eTaskConfirmSleepModeStatus( void );
+eSleepModeStatus eTaskConfirmSleepModeStatus( void ) PRIVILEGED_FUNCTION;
 
 #ifdef __cplusplus
 }
diff --git a/FreeRTOS/Source/include/timers.h b/FreeRTOS/Source/include/timers.h
index 01a09f371..f41ac583b 100644
--- a/FreeRTOS/Source/include/timers.h
+++ b/FreeRTOS/Source/include/timers.h
@@ -1,5 +1,5 @@
 /*
-    FreeRTOS V7.6.0 - Copyright (C) 2013 Real Time Engineers Ltd. 
+    FreeRTOS V7.6.0 - Copyright (C) 2013 Real Time Engineers Ltd.
     All rights reserved
 
     VISIT http://www.FreeRTOS.org TO ENSURE YOU ARE USING THE LATEST VERSION.
@@ -83,6 +83,7 @@ extern "C" {
 /* IDs for commands that can be sent/received on the timer queue.  These are to
 be used solely through the macros that make up the public software timer API,
 as defined below. */
+#define tmrCOMMAND_EXECUTE_CALLBACK			( ( portBASE_TYPE ) -1 )
 #define tmrCOMMAND_START					( ( portBASE_TYPE ) 0 )
 #define tmrCOMMAND_STOP						( ( portBASE_TYPE ) 1 )
 #define tmrCOMMAND_CHANGE_PERIOD			( ( portBASE_TYPE ) 2 )
@@ -170,7 +171,7 @@ typedef void (*tmrTIMER_CALLBACK)( xTimerHandle xTimer );
  *
  * 	   // Optionally do something if the pxTimer parameter is NULL.
  * 	   configASSERT( pxTimer );
- * 	
+ *
  *     // Which timer expired?
  *     lArrayIndex = ( long ) pvTimerGetTimerID( pxTimer );
  *
@@ -293,7 +294,7 @@ void *pvTimerGetTimerID( xTimerHandle xTimer ) PRIVILEGED_FUNCTION;
 portBASE_TYPE xTimerIsTimerActive( xTimerHandle xTimer ) PRIVILEGED_FUNCTION;
 
 /**
- * xTimerGetTimerDaemonTaskHandle() is only available if 
+ * xTimerGetTimerDaemonTaskHandle() is only available if
  * INCLUDE_xTimerGetTimerDaemonTaskHandle is set to 1 in FreeRTOSConfig.h.
  *
  * Simply returns the handle of the timer service/daemon task.  It it not valid
@@ -944,6 +945,95 @@ xTaskHandle xTimerGetTimerDaemonTaskHandle( void );
  */
 #define xTimerResetFromISR( xTimer, pxHigherPriorityTaskWoken ) xTimerGenericCommand( ( xTimer ), tmrCOMMAND_START, ( xTaskGetTickCountFromISR() ), ( pxHigherPriorityTaskWoken ), 0U )
 
+
+/**
+ * portBASE_TYPE xTimerPendCallbackFromISR( pdAPPLICATION_CALLBACK_CODE pvCallbackFunction,
+ *                                          void *pvParameter1,
+ *                                          unsigned long ulParameter2,
+ *                                          portBASE_TYPE *pxHigherPriorityTaskWoken );
+ *
+ *
+ * Can be used by interrupt service routines to request that a function (the
+ * callback function) is executed from a task context.
+ *
+ * Ideally an interrupt service routine (ISR) is kept as short as possible, but
+ * sometimes an ISR either has a lot of processing to do, or needs to perform
+ * processing that is not deterministic.  In these cases the processing can be
+ * deferred to be performed in a task - allowing the ISR to exit.  The timer
+ * daemon service/daemon task is already responsible for executing software
+ * timer callback functions, so is also used to executed callback functions that
+ * are pended from interrupts.
+ *
+ * A mechanism is provided that allows the interrupt to return directly to the
+ * task that will subsequently execute the pended callback function.  This
+ * allows the callback function to execute contiguously in time with the
+ * interrupt - just as if the callback had executed in the interrupt itself.
+ *
+ * @param pvCallbackFunction The function to execute from the timer service/
+ * daemon task.  The function must conform to the pdAPPLICATION_CALLBACK_CODE
+ * prototype.
+ *
+ * @param pvParameter1 The value of the callback function's first parameter.
+ * The parameter has a void * type to allow it to be used to pass any type.
+ * For example, unsigned longs can be cast to a void *, or the void * can be
+ * used to point to a structure.
+ *
+ * @param ulParameter2 The value of the callback function's second parameter.
+ *
+ * @param pxHigherPriorityTaskWoken As mentioned above, calling this function
+ * will result in a message being sent to the timer daemon task.  If the
+ * priority of the timer daemon task (which is set using
+ * configTIMER_TASK_PRIORITY in FreeRTOSConfig.h) is higher than the priority of
+ * the currently running task (the task the interrupt interrupted) then
+ * *pxHigherPriorityTaskWoken will be set to pdTRUE within
+ * xTimerPendCallbackFromISR(), indicating that a context switch should be
+ * requested before the interrupt exits.  For that reason
+ * *pxHigherPriorityTaskWoken must be initialised to pdFALSE.  See the
+ * example code below.
+ *
+ * Example usage:
+ * @verbatim
+ *
+ *	// The callback function that will execute in the context of the daemon task.
+ *  // Note callback functions must all use this same prototype.
+ *  void vProcessInterface( void *pvParameter1, unsigned long ulParameter2 )
+ *	{
+ *		portBASE_TYPE xInterfaceToService;
+ *
+ *		// The interface that requires servicing is passed in the second
+ *      // parameter.  The first parameter is not used in this case.
+ *		xInterfaceToService = ( portBASE_TYPE ) ulParameter2;
+ *
+ *		// ...Perform the processing here...
+ *	}
+ *
+ *	// An ISR that receives data packets from multiple interfaces
+ *  void vAnISR( void )
+ *	{
+ *		portBASE_TYPE xInterfaceToService, xHigherPriorityTaskWoken;
+ *
+ *		// Query the hardware to determine which interface needs processing.
+ *		xInterfaceToService = prvCheckInterfaces();
+ *
+ *      // The actual processing is to be deferred to a task.  Request the
+ *      // vProcessInterface() callback function is executed, passing in the
+ *		// number of the interface that needs processing.  The interface to
+ *		// service is passed in the second parameter.  The first parameter is
+ *		// not used in this case.
+ *		xHigherPriorityTaskWoken = pdFALSE;
+ *		xTimerPendCallbackFromISR( vProcessInterface, NULL, ( unsigned long ) xInterfaceToService, &xHigherPriorityTaskWoken );
+ *
+ *		// If xHigherPriorityTaskWoken is now set to pdTRUE then a context
+ *		// switch should be requested.  The macro used is port specific and will
+ *		// be either portYIELD_FROM_ISR() or portEND_SWITCHING_ISR() - refer to
+ *		// the documentation page for the port being used.
+ *		portYIELD_FROM_ISR( xHigherPriorityTaskWoken );
+ *
+ *	}
+ * @endverbatim
+ */
+portBASE_TYPE xTimerPendCallbackFromISR( pdAPPLICATION_CALLBACK_CODE pvCallbackFunction, void *pvParameter1, unsigned long ulParameter2, portBASE_TYPE *pxHigherPriorityTaskWoken );
+
 /*
  * Functions beyond this part are not part of the public API and are intended
  * for use by the kernel only.
diff --git a/FreeRTOS/Source/portable/MemMang/heap_4.c b/FreeRTOS/Source/portable/MemMang/heap_4.c
index 21a202ee8..4ed42b8de 100644
--- a/FreeRTOS/Source/portable/MemMang/heap_4.c
+++ b/FreeRTOS/Source/portable/MemMang/heap_4.c
@@ -134,6 +134,7 @@ static xBlockLink xStart, *pxEnd = NULL;
 /* Keeps track of the number of free bytes remaining, but says nothing about
 fragmentation. */
 static size_t xFreeBytesRemaining = ( ( size_t ) heapADJUSTED_HEAP_SIZE ) & ( ( size_t ) ~portBYTE_ALIGNMENT_MASK );
+static size_t xMinimumEverFreeBytesRemaining = ( ( size_t ) heapADJUSTED_HEAP_SIZE ) & ( ( size_t ) ~portBYTE_ALIGNMENT_MASK );
 
 /* Gets set to the top bit of an size_t type.  When this bit in the xBlockSize 
 member of an xBlockLink structure is set then the block belongs to the 
@@ -223,6 +224,11 @@ void *pvReturn = NULL;
 
 					xFreeBytesRemaining -= pxBlock->xBlockSize;
 
+					if( xFreeBytesRemaining < xMinimumEverFreeBytesRemaining )
+					{
+						xMinimumEverFreeBytesRemaining = xFreeBytesRemaining;
+					}
+
 					/* The block is being returned - it is allocated and owned
 					by the application and has no "next" block. */
 					pxBlock->xBlockSize |= xBlockAllocatedBit;
@@ -295,6 +301,12 @@ size_t xPortGetFreeHeapSize( void )
 }
 /*-----------------------------------------------------------*/
 
+size_t xPortGetMinimumEverFreeHeapSize( void )
+{
+	return xMinimumEverFreeBytesRemaining;
+}
+/*-----------------------------------------------------------*/
+
 void vPortInitialiseBlocks( void )
 {
 	/* This just exists to keep the linker quiet. */
diff --git a/FreeRTOS/Source/tasks.c b/FreeRTOS/Source/tasks.c
index c0f151958..f23143271 100644
--- a/FreeRTOS/Source/tasks.c
+++ b/FreeRTOS/Source/tasks.c
@@ -169,7 +169,6 @@ typedef struct tskTaskControlBlock
 
 } tskTCB;
 
-
 /*
  * Some kernel aware debuggers require the data the debugger needs access to to
  * be global, rather than file scope.
@@ -1327,7 +1326,9 @@ void vTaskEndScheduler( void )
 void vTaskSuspendAll( void )
 {
 	/* A critical section is not required as the variable is of type
-	portBASE_TYPE. */
+	portBASE_TYPE.  Please read Richard Barry's reply in the following link to a
+	post in the FreeRTOS support forum before reporting this as a bug! -
+	http://goo.gl/wu4acr */
 	++uxSchedulerSuspended;
 }
 /*----------------------------------------------------------*/
@@ -1938,6 +1939,60 @@ portTickType xTimeToWake;
 }
 /*-----------------------------------------------------------*/
 
+void vTaskPlaceOnUnorderedEventList( xList * pxEventList, portTickType xItemValue, portTickType xTicksToWait )
+{
+portTickType xTimeToWake;
+
+	configASSERT( pxEventList );
+
+	/* THIS FUNCTION MUST BE CALLED WITH INTERRUPTS DISABLED OR THE
+	SCHEDULER SUSPENDED. */
+
+	/* Store the item value in the event list item. */
+	listSET_LIST_ITEM_VALUE( &( pxCurrentTCB->xEventListItem ), xItemValue );
+
+	/* Place the event list item of the TCB at the end of the appropriate event 
+	list. */
+	vListInsertEnd( pxEventList, &( pxCurrentTCB->xEventListItem ) );
+
+	/* The task must be removed from the ready list before it is added to the
+	blocked list.  Exclusive access can be assured to the ready list as the
+	scheduler is locked. */
+	if( uxListRemove( &( pxCurrentTCB->xGenericListItem ) ) == ( unsigned portBASE_TYPE ) 0 )
+	{
+		/* The current task must be in a ready list, so there is no need to
+		check, and the port reset macro can be called directly. */
+		portRESET_READY_PRIORITY( pxCurrentTCB->uxPriority, uxTopReadyPriority );
+	}
+
+	#if ( INCLUDE_vTaskSuspend == 1 )
+	{
+		if( xTicksToWait == portMAX_DELAY )
+		{
+			/* Add the task to the suspended task list instead of a delayed task
+			list to ensure it is not woken by a timing event.  It will block
+			indefinitely. */
+			vListInsertEnd( &xSuspendedTaskList, &( pxCurrentTCB->xGenericListItem ) );
+		}
+		else
+		{
+			/* Calculate the time at which the task should be woken if the event does
+			not occur.  This may overflow but this doesn't matter. */
+			xTimeToWake = xTickCount + xTicksToWait;
+			prvAddCurrentTaskToDelayedList( xTimeToWake );
+		}
+	}
+	#else /* INCLUDE_vTaskSuspend */
+	{
+			/* Calculate the time at which the task should be woken if the event does
+			not occur.  This may overflow but this doesn't matter. */
+			xTimeToWake = xTickCount + xTicksToWait;
+			prvAddCurrentTaskToDelayedList( xTimeToWake );
+	}
+	#endif /* INCLUDE_vTaskSuspend */
+}
+/*-----------------------------------------------------------*/
+
 #if configUSE_TIMERS == 1
 
 	void vTaskPlaceOnEventListRestricted( xList * const pxEventList, portTickType xTicksToWait )
@@ -2034,6 +2089,56 @@ portBASE_TYPE xReturn;
 }
 /*-----------------------------------------------------------*/
 
+signed portBASE_TYPE xTaskRemoveFromUnorderedEventList( xListItem * pxEventListItem, portTickType xItemValue )
+{
+tskTCB *pxUnblockedTCB;
+portBASE_TYPE xReturn;
+
+	/* THIS FUNCTION MUST BE CALLED WITH INTERRUPTS DISABLED OR THE
+	SCHEDULER SUSPENDED.  It can also be called from within an ISR. */
+
+	/* Store the new item value in the event list. */
+	listSET_LIST_ITEM_VALUE( pxEventListItem, xItemValue );
+
+	/* Remove the TCB from the delayed list, and add it to the ready list. */
+
+	pxUnblockedTCB = ( tskTCB * ) listGET_LIST_ITEM_OWNER( pxEventListItem );
+	configASSERT( pxUnblockedTCB );
+	( void ) uxListRemove( pxEventListItem );
+
+	if( uxSchedulerSuspended == ( unsigned portBASE_TYPE ) pdFALSE )
+	{
+		( void ) uxListRemove( &( pxUnblockedTCB->xGenericListItem ) );
+		prvAddTaskToReadyList( pxUnblockedTCB );
+	}
+	else
+	{
+		/* Cannot access the delayed or ready lists, so will hold this task 
+		pending until the scheduler is resumed. */
+		vListInsertEnd( &( xPendingReadyList ), pxEventListItem );
+	}
+
+	if( pxUnblockedTCB->uxPriority >= pxCurrentTCB->uxPriority )
+	{
+		/* Return true if the task removed from the event list has
+		a higher priority than the calling task.  This allows
+		the calling task to know if it should force a context
+		switch now. */
+		xReturn = pdTRUE;
+
+		/* Mark that a yield is pending in case the user is not using the
+		"xHigherPriorityTaskWoken" parameter to an ISR safe FreeRTOS function. */
+		xYieldPending = pdTRUE;
+	}
+	else
+	{
+		xReturn = pdFALSE;
+	}
+
+	return xReturn;
+}
+/*-----------------------------------------------------------*/
+
 void vTaskSetTimeOutState( xTimeOutType * const pxTimeOut )
 {
 	configASSERT( pxTimeOut );
@@ -2973,6 +3078,20 @@ tskTCB *pxNewTCB;
 	}
 
 #endif /* configGENERATE_RUN_TIME_STATS */
+/*-----------------------------------------------------------*/
 
+portTickType uxTaskResetEventItemValue( void )
+{
+portTickType uxReturn;
+
+	uxReturn = listGET_LIST_ITEM_VALUE( &( pxCurrentTCB->xEventListItem ) );
+
+	/* Reset the event list item to its normal value - so it can be used with
+	queues and semaphores. */
+	listSET_LIST_ITEM_VALUE( &( pxCurrentTCB->xEventListItem ), ( ( portTickType ) configMAX_PRIORITIES - ( portTickType ) pxCurrentTCB->uxPriority ) ); /*lint !e961 MISRA exception as the casts are only redundant for some ports. */
+
+	return uxReturn;
+}
+/*-----------------------------------------------------------*/
 
 
diff --git a/FreeRTOS/Source/timers.c b/FreeRTOS/Source/timers.c
index aeaae2f30..eebc99646 100644
--- a/FreeRTOS/Source/timers.c
+++ b/FreeRTOS/Source/timers.c
@@ -1,5 +1,5 @@
 /*
-    FreeRTOS V7.6.0 - Copyright (C) 2013 Real Time Engineers Ltd. 
+    FreeRTOS V7.6.0 - Copyright (C) 2013 Real Time Engineers Ltd.
     All rights reserved
 
     VISIT http://www.FreeRTOS.org TO ENSURE YOU ARE USING THE LATEST VERSION.
@@ -76,6 +76,10 @@ task.h is included from an application file. */
 #include "queue.h"
 #include "timers.h"
 
+#if ( INCLUDE_xTimerPendCallbackFromISR == 1 ) && ( configUSE_TIMERS == 0 )
+	#error configUSE_TIMERS must be set to 1 to make the INCLUDE_xTimerPendCallbackFromISR() function available.
+#endif
+
 /* Lint e961 and e750 are suppressed as a MISRA exception justified because the
 MPU ports require MPU_WRAPPERS_INCLUDED_FROM_API_FILE to be defined for the
 header files above, but not in this file, in order to generate the correct
@@ -103,14 +107,41 @@ typedef struct tmrTimerControl
 	tmrTIMER_CALLBACK		pxCallbackFunction;	/*<< The function that will be called when the timer expires. */
 } xTIMER;
 
-/* The definition of messages that can be sent and received on the timer
-queue. */
-typedef struct tmrTimerQueueMessage
+/* The definition of messages that can be sent and received on the timer queue.
+Two types of message can be queued - messages that manipulate a software timer,
+and messages that request the execution of a non-timer related callback.  The
+two message types are defined in two separate structures, xTimerParametersType
+and xCallbackParametersType respectively. */
+typedef struct tmrTimerParameters
 {
-	portBASE_TYPE			xMessageID;			/*<< The command being sent to the timer service task. */
 	portTickType			xMessageValue;		/*<< An optional value used by a subset of commands, for example, when changing the period of a timer. */
 	xTIMER *				pxTimer;			/*<< The timer to which the command will be applied. */
-} xTIMER_MESSAGE;
+} xTimerParametersType;
+
+
+typedef struct tmrCallbackParameters
+{
+	pdAPPLICATION_CALLBACK_CODE	pxCallbackFunction; /* << The callback function to execute. */
+	void *pvParameter1;								/* << The value that will be used as the callback functions first parameter. */
+	unsigned long ulParameter2;						/* << The value that will be used as the callback functions second parameter. */
+} xCallbackParametersType;
+
+/* The structure that contains the two message types, along with an identifier
+that is used to determine which message type is valid. */
+typedef struct tmrTimerQueueMessage
+{
+	portBASE_TYPE			xMessageID;			/*<< The command being sent to the timer service task. */
+	union
+	{
+		xTimerParametersType xTimerParameters;
+
+		/* Don't include xCallbackParameters if it is not going to be used as
+		it makes the structure (and therefore the timer queue) larger. */
+		#if ( INCLUDE_xTimerPendCallbackFromISR == 1 )
+			xCallbackParametersType xCallbackParameters;
+		#endif /* INCLUDE_xTimerPendCallbackFromISR */
+	} u;
+} xDAEMON_TASK_MESSAGE;
 
 /*lint -e956 A manual analysis and inspection has been used to determine which
 static variables must be declared volatile. */
@@ -270,7 +301,7 @@ xTIMER *pxNewTimer;
 portBASE_TYPE xTimerGenericCommand( xTimerHandle xTimer, portBASE_TYPE xCommandID, portTickType xOptionalValue, signed portBASE_TYPE *pxHigherPriorityTaskWoken, portTickType xBlockTime )
 {
 portBASE_TYPE xReturn = pdFAIL;
-xTIMER_MESSAGE xMessage;
+xDAEMON_TASK_MESSAGE xMessage;
 
 	/* Send a message to the timer service task to perform a particular action
 	on a particular timer definition. */
@@ -278,8 +309,8 @@ xTIMER_MESSAGE xMessage;
 	{
 		/* Send a command to the timer service task to start the xTimer timer. */
 		xMessage.xMessageID = xCommandID;
-		xMessage.xMessageValue = xOptionalValue;
-		xMessage.pxTimer = ( xTIMER * ) xTimer;
+		xMessage.u.xTimerParameters.xMessageValue = xOptionalValue;
+		xMessage.u.xTimerParameters.pxTimer = ( xTIMER * ) xTimer;
 
 		if( pxHigherPriorityTaskWoken == NULL )
 		{
@@ -518,77 +549,98 @@ portBASE_TYPE xProcessTimerNow = pdFALSE;
 
 static void	prvProcessReceivedCommands( void )
 {
-xTIMER_MESSAGE xMessage;
+xDAEMON_TASK_MESSAGE xMessage;
 xTIMER *pxTimer;
 portBASE_TYPE xTimerListsWereSwitched, xResult;
 portTickType xTimeNow;
 
 	while( xQueueReceive( xTimerQueue, &xMessage, tmrNO_DELAY ) != pdFAIL ) /*lint !e603 xMessage does not have to be initialised as it is passed out, not in, and it is not used unless xQueueReceive() returns pdTRUE. */
 	{
-		pxTimer = xMessage.pxTimer;
-
-		if( listIS_CONTAINED_WITHIN( NULL, &( pxTimer->xTimerListItem ) ) == pdFALSE )
+		#if ( INCLUDE_xTimerPendCallbackFromISR == 1 )
 		{
-			/* The timer is in a list, remove it. */
-			( void ) uxListRemove( &( pxTimer->xTimerListItem ) );
-		}
+			if( xMessage.xMessageID == tmrCOMMAND_EXECUTE_CALLBACK )
+			{
+				const xCallbackParametersType * const pxCallback = &( xMessage.u.xCallbackParameters );
 
-		traceTIMER_COMMAND_RECEIVED( pxTimer, xMessage.xMessageID, xMessage.xMessageValue );
+				/* The timer uses the xCallbackParameters member to request a
+				callback be executed.  Check the callback is not NULL. */
+				configASSERT( pxCallback );
 
-		/* In this case the xTimerListsWereSwitched parameter is not used, but 
-		it must be present in the function call.  prvSampleTimeNow() must be 
-		called after the message is received from xTimerQueue so there is no 
-		possibility of a higher priority task adding a message to the message
-		queue with a time that is ahead of the timer daemon task (because it
-		pre-empted the timer daemon task after the xTimeNow value was set). */
-		xTimeNow = prvSampleTimeNow( &xTimerListsWereSwitched );
+				/* Call the function. */
+				pxCallback->pxCallbackFunction( pxCallback->pvParameter1, pxCallback->ulParameter2 );
+			}
+		}
+		#endif /* INCLUDE_xTimerPendCallbackFromISR */
 
-		switch( xMessage.xMessageID )
+		if( xMessage.xMessageID != tmrCOMMAND_EXECUTE_CALLBACK )
 		{
-			case tmrCOMMAND_START :
-				/* Start or restart a timer. */
-				if( prvInsertTimerInActiveList( pxTimer,  xMessage.xMessageValue + pxTimer->xTimerPeriodInTicks, xTimeNow, xMessage.xMessageValue ) == pdTRUE )
-				{
-					/* The timer expired before it was added to the active timer
-					list.  Process it now. */
-					pxTimer->pxCallbackFunction( ( xTimerHandle ) pxTimer );
+			/* The messages uses the xTimerParameters member to work on a
+			software timer. */
+			pxTimer = xMessage.u.xTimerParameters.pxTimer;
+
+			if( listIS_CONTAINED_WITHIN( NULL, &( pxTimer->xTimerListItem ) ) == pdFALSE )
+			{
+				/* The timer is in a list, remove it. */
+				( void ) uxListRemove( &( pxTimer->xTimerListItem ) );
+			}
+
+			traceTIMER_COMMAND_RECEIVED( pxTimer, xMessage.xMessageID, xMessage.u.xTimerParameters.xMessageValue );
 
-					if( pxTimer->uxAutoReload == ( unsigned portBASE_TYPE ) pdTRUE )
+			/* In this case the xTimerListsWereSwitched parameter is not used, but
+			it must be present in the function call.  prvSampleTimeNow() must be
+			called after the message is received from xTimerQueue so there is no
+			possibility of a higher priority task adding a message to the message
+			queue with a time that is ahead of the timer daemon task (because it
+			pre-empted the timer daemon task after the xTimeNow value was set). */
+			xTimeNow = prvSampleTimeNow( &xTimerListsWereSwitched );
+
+			switch( xMessage.xMessageID )
+			{
+				case tmrCOMMAND_START :
+					/* Start or restart a timer. */
+					if( prvInsertTimerInActiveList( pxTimer,  xMessage.u.xTimerParameters.xMessageValue + pxTimer->xTimerPeriodInTicks, xTimeNow, xMessage.u.xTimerParameters.xMessageValue ) == pdTRUE )
 					{
-						xResult = xTimerGenericCommand( pxTimer, tmrCOMMAND_START, xMessage.xMessageValue + pxTimer->xTimerPeriodInTicks, NULL, tmrNO_DELAY );
-						configASSERT( xResult );
-						( void ) xResult;
+						/* The timer expired before it was added to the active timer
+						list.  Process it now. */
+						pxTimer->pxCallbackFunction( ( xTimerHandle ) pxTimer );
+
+						if( pxTimer->uxAutoReload == ( unsigned portBASE_TYPE ) pdTRUE )
+						{
+							xResult = xTimerGenericCommand( pxTimer, tmrCOMMAND_START, xMessage.u.xTimerParameters.xMessageValue + pxTimer->xTimerPeriodInTicks, NULL, tmrNO_DELAY );
+							configASSERT( xResult );
+							( void ) xResult;
+						}
 					}
-				}
-				break;
-
-			case tmrCOMMAND_STOP :
-				/* The timer has already been removed from the active list.
-				There is nothing to do here. */
-				break;
-
-			case tmrCOMMAND_CHANGE_PERIOD :
-				pxTimer->xTimerPeriodInTicks = xMessage.xMessageValue;
-				configASSERT( ( pxTimer->xTimerPeriodInTicks > 0 ) );
-
-				/* The new period does not really have a reference, and can be
-				longer or shorter than the old one.  The command time is 
-				therefore set to the current time, and as the period cannot be
-				zero the next expiry time can only be in the future, meaning
-				(unlike for the xTimerStart() case above) there is no fail case
-				that needs to be handled here. */
-				( void ) prvInsertTimerInActiveList( pxTimer, ( xTimeNow + pxTimer->xTimerPeriodInTicks ), xTimeNow, xTimeNow );
-				break;
-
-			case tmrCOMMAND_DELETE :
-				/* The timer has already been removed from the active list,
-				just free up the memory. */
-				vPortFree( pxTimer );
-				break;
-
-			default	:
-				/* Don't expect to get here. */
-				break;
+					break;
+
+				case tmrCOMMAND_STOP :
+					/* The timer has already been removed from the active list.
+					There is nothing to do here. */
+					break;
+
+				case tmrCOMMAND_CHANGE_PERIOD :
+					pxTimer->xTimerPeriodInTicks = xMessage.u.xTimerParameters.xMessageValue;
+					configASSERT( ( pxTimer->xTimerPeriodInTicks > 0 ) );
+
+					/* The new period does not really have a reference, and can be
+					longer or shorter than the old one.  The command time is
+					therefore set to the current time, and as the period cannot be
+					zero the next expiry time can only be in the future, meaning
+					(unlike for the xTimerStart() case above) there is no fail case
+					that needs to be handled here. */
+					( void ) prvInsertTimerInActiveList( pxTimer, ( xTimeNow + pxTimer->xTimerPeriodInTicks ), xTimeNow, xTimeNow );
+					break;
+
+				case tmrCOMMAND_DELETE :
+					/* The timer has already been removed from the active list,
+					just free up the memory. */
+					vPortFree( pxTimer );
+					break;
+
+				default	:
+					/* Don't expect to get here. */
+					break;
+			}
 		}
 	}
 }
@@ -664,7 +716,7 @@ static void prvCheckForValidListAndQueue( void )
 			vListInitialise( &xActiveTimerList2 );
 			pxCurrentTimerList = &xActiveTimerList1;
 			pxOverflowTimerList = &xActiveTimerList2;
-			xTimerQueue = xQueueCreate( ( unsigned portBASE_TYPE ) configTIMER_QUEUE_LENGTH, sizeof( xTIMER_MESSAGE ) );
+			xTimerQueue = xQueueCreate( ( unsigned portBASE_TYPE ) configTIMER_QUEUE_LENGTH, sizeof( xDAEMON_TASK_MESSAGE ) );
 		}
 	}
 	taskEXIT_CRITICAL();
@@ -698,6 +750,28 @@ xTIMER *pxTimer = ( xTIMER * ) xTimer;
 }
 /*-----------------------------------------------------------*/
 
+#if( INCLUDE_xTimerPendCallbackFromISR == 1 )
+
+	portBASE_TYPE xTimerPendCallbackFromISR( pdAPPLICATION_CALLBACK_CODE pvCallbackFunction, void *pvParameter1, unsigned long ulParameter2, portBASE_TYPE *pxHigherPriorityTaskWoken )
+	{
+	xDAEMON_TASK_MESSAGE xMessage;
+	portBASE_TYPE xReturn;
+
+		/* Complete the message with the function parameters and post it to the
+		daemon task. */
+		xMessage.xMessageID = tmrCOMMAND_EXECUTE_CALLBACK;
+		xMessage.u.xCallbackParameters.pxCallbackFunction = pvCallbackFunction;
+		xMessage.u.xCallbackParameters.pvParameter1 = pvParameter1;
+		xMessage.u.xCallbackParameters.ulParameter2 = ulParameter2;
+
+		xReturn = xQueueSendFromISR( xTimerQueue, &xMessage, pxHigherPriorityTaskWoken );
+
+		return xReturn;
+	}
+
+#endif /* INCLUDE_xTimerPendCallbackFromISR */
+/*-----------------------------------------------------------*/
+
 /* This entire source file will be skipped if the application is not configured
 to include software timer functionality.  If you want to include software timer
 functionality then ensure configUSE_TIMERS is set to 1 in FreeRTOSConfig.h. */
-- 
2.39.2