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/*
FreeRTOS V8.1.0 - Copyright (C) 2014 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!
*/
#include "FreeRTOSConfig.h"
#include "portasm.h"
IMPORT xTaskIncrementTick
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 #xTaskIncrementTick
cmp.w #0x0, R12
jeq SkipContextSwitch
call #vTaskSwitchContext
SkipContextSwitch:
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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