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/*
FreeRTOS.org V5.1.2 - Copyright (C) 2003-2009 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.
***************************************************************************
***************************************************************************
* *
* Get the FreeRTOS eBook! See http://www.FreeRTOS.org/Documentation *
* *
* This is a concise, step by step, 'hands on' guide that describes both *
* general multitasking concepts and FreeRTOS specifics. It presents and *
* explains numerous examples that are written using the FreeRTOS API. *
* Full source code for all the examples is provided in an accompanying *
* .zip file. *
* *
***************************************************************************
***************************************************************************
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
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