portext.s43

FreeRTOS - V5.1.1 Last Update: Nov 20 2008 http://sourceforge.net/projects/freertos/

/*
	FreeRTOS.org V5.1.1 - Copyright (C) 2003-2008 Richard Barry.

	This file is part of the FreeRTOS.org distribution.

	FreeRTOS.org is free software; you can redistribute it and/or modify
	it under the terms of the GNU General Public License as published by
	the Free Software Foundation; either version 2 of the License, or
	(at your option) any later version.

	FreeRTOS.org 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.  See the
	GNU General Public License for more details.

	You should have received a copy of the GNU General Public License
	along with FreeRTOS.org; if not, write to the Free Software
	Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

	A special exception to the GPL can be applied should you wish to distribute
	a combined work that includes FreeRTOS.org, without being obliged to provide
	the source code for any proprietary components.  See the licensing section
	of http://www.FreeRTOS.org for full details of how and when the exception
	can be applied.

    ***************************************************************************
    ***************************************************************************
    *                                                                         *
    * SAVE TIME AND MONEY!  We can port FreeRTOS.org to your own hardware,    *
    * and even write all or part of your application on your behalf.          *
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    * expedite your project.                                                  *
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    ***************************************************************************
    ***************************************************************************

	Please ensure to read the configuration and relevant port sections of the
	online documentation.

	http://www.FreeRTOS.org - Documentation, latest information, license and
	contact details.

	http://www.SafeRTOS.com - A version that is certified for use in safety
	critical systems.

	http://www.OpenRTOS.com - Commercial support, development, porting,
	licensing and training services.
*/
#include "FreeRTOSConfig.h"
#include "portasm.h"

	IMPORT vTaskIncrementTick
	IMPORT vTaskSwitchContext
	IMPORT vPortSetupTimerInterrupt

	EXPORT vTickISR
	EXPORT vPortYield
	EXPORT xPortStartScheduler
	
	RSEG CODE

/*
 * The RTOS tick ISR.
 *
 * If the cooperative scheduler is in use this simply increments the tick
 * count.
 *
 * If the preemptive scheduler is in use a context switch can also occur.
 */
vTickISR:
	portSAVE_CONTEXT
				
	call	#vTaskIncrementTick

	#if configUSE_PREEMPTION == 1
		call	#vTaskSwitchContext
	#endif
		
	portRESTORE_CONTEXT
/*-----------------------------------------------------------*/


/*
 * Manual context switch called by the portYIELD() macro.
 */
vPortYield:

	/* Mimic an interrupt by pushing the SR. */
	push	SR			

	/* Now the SR is stacked we can disable interrupts. */
	dint			
				
	/* Save the context of the current task. */
	portSAVE_CONTEXT			

	/* Switch to the highest priority task that is ready to run. */
	call	#vTaskSwitchContext		

	/* Restore the context of the new task. */
	portRESTORE_CONTEXT
/*-----------------------------------------------------------*/


/*
 * Start off the scheduler by initialising the RTOS tick timer, then restoring
 * the context of the first task.
 */
xPortStartScheduler:

	/* Setup the hardware to generate the tick.  Interrupts are disabled
	when this function is called. */
	call	#vPortSetupTimerInterrupt

	/* Restore the context of the first task that is going to run. */
	portRESTORE_CONTEXT
/*-----------------------------------------------------------*/
      		

	/* Install vTickISR as the timer A0 interrupt. */
	ASEG
	ORG 0xFFE0 + TIMERA0_VECTOR
	
	_vTickISR_: DC16 vTickISR
	

	END