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/*
FreeRTOS V8.2.3 - Copyright (C) 2015 Real Time Engineers Ltd.
All rights reserved
VISIT http://www.FreeRTOS.org TO ENSURE YOU ARE USING THE LATEST VERSION.
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 on the following
link: http://www.freertos.org/a00114.html
***************************************************************************
* *
* FreeRTOS provides completely free yet professionally developed, *
* robust, strictly quality controlled, supported, and cross *
* platform software that is more than just the market leader, it *
* is the industry's de facto standard. *
* *
* Help yourself get started quickly while simultaneously helping *
* to support the FreeRTOS project by purchasing a FreeRTOS *
* tutorial book, reference manual, or both: *
* http://www.FreeRTOS.org/Documentation *
* *
***************************************************************************
http://www.FreeRTOS.org/FAQHelp.html - Having a problem? Start by reading
the FAQ page "My application does not run, what could be wrong?". Have you
defined configASSERT()?
http://www.FreeRTOS.org/support - In return for receiving this top quality
embedded software for free we request you assist our global community by
participating in the support forum.
http://www.FreeRTOS.org/training - Investing in training allows your team to
be as productive as possible as early as possible. Now you can receive
FreeRTOS training directly from Richard Barry, CEO of Real Time Engineers
Ltd, and the world's leading authority on the world's leading RTOS.
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.FreeRTOS.org/labs - Where new FreeRTOS products go to incubate.
Come and try FreeRTOS+TCP, our new open source TCP/IP stack for FreeRTOS.
http://www.OpenRTOS.com - Real Time Engineers ltd. license FreeRTOS to High
Integrity Systems ltd. to sell under the OpenRTOS brand. Low cost OpenRTOS
licenses offer ticketed support, indemnification and commercial 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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