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;/*
; FreeRTOS V8.1.2 - Copyright (C) 2014 Real Time Engineers Ltd.
; All rights reserved
;
;
; ***************************************************************************
; * *
; * FreeRTOS tutorial books are available in pdf and paperback. *
; * Complete, revised, and edited pdf reference manuals are also *
; * available. *
; * *
; * Purchasing FreeRTOS documentation will not only help you, by *
; * ensuring you get running as quickly as possible and with an *
; * in-depth knowledge of how to use FreeRTOS, it will also help *
; * the FreeRTOS project to continue with its mission of providing *
; * professional grade, cross platform, de facto standard solutions *
; * for microcontrollers - completely free of charge! *
; * *
; * >>> See http://www.FreeRTOS.org/Documentation for details. <<< *
; * *
; * Thank you for using FreeRTOS, and thank you for your support! *
; * *
; ***************************************************************************
;
;
; 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. See the GNU General Public License for
; more details. You should have received a copy of the GNU General Public
; License and the FreeRTOS license exception along with FreeRTOS; if not it
; can be viewed here: http://www.freertos.org/a00114.html and also obtained
; by writing to Richard Barry, contact details for whom are available on the
; FreeRTOS WEB site.
;
; 1 tab == 4 spaces!
;
; 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.
;*/
RSEG ICODE:CODE
CODE32
EXTERN vPortPreemptiveTick
EXTERN vTaskSwitchContext
PUBLIC vPortYieldProcessor
PUBLIC vPortStartFirstTask
PUBLIC vPortPreemptiveTickISR
#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.
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
; Preemptive context switch function. This will only ever get used if
; portUSE_PREEMPTION is set to 1 in portmacro.h.
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
vPortPreemptiveTickISR:
portSAVE_CONTEXT ; Save the context of the current task.
LDR R0, =vPortPreemptiveTick ; Increment the tick count - this may wake a task.
MOV lr, pc
BX R0
portRESTORE_CONTEXT ; Restore the context of the selected task.
END
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