;/* | |
; FreeRTOS.org V5.4.0 - Copyright (C) 2003-2009 Richard Barry. | |
; | |
; This file is part of the FreeRTOS.org distribution. | |
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; *************************************************************************** | |
; * * | |
; * 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. * | |
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; *************************************************************************** | |
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; Please ensure to read the configuration and relevant port sections of the | |
; online documentation. | |
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; http://www.FreeRTOS.org - Documentation, latest information, license and | |
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; http://www.SafeRTOS.com - A version that is certified for use in safety | |
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; http://www.OpenRTOS.com - Commercial support, development, porting, | |
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;*/ | |
RSEG ICODE:CODE | |
CODE32 | |
EXTERN vPortPreemptiveTick | |
EXTERN vTaskSwitchContext | |
PUBLIC vPortYieldProcessor | |
PUBLIC vPortStartFirstTask | |
#include "ISR_Support.h" | |
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; | |
; Starting the first task is just a matter of restoring the context that | |
; was created by pxPortInitialiseStack(). | |
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; | |
vPortStartFirstTask: | |
portRESTORE_CONTEXT | |
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; | |
; Manual context switch function. This is the SWI hander. | |
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; | |
vPortYieldProcessor: | |
ADD LR, LR, #4 ; Add 4 to the LR to make the LR appear exactly | |
; as if the context was saved during and IRQ | |
; handler. | |
portSAVE_CONTEXT ; Save the context of the current task... | |
LDR R0, =vTaskSwitchContext ; before selecting the next task to execute. | |
mov lr, pc | |
BX R0 | |
portRESTORE_CONTEXT ; Restore the context of the selected task. | |
END | |