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; FreeRTOS.org V5.1.1 - Copyright (C) 2003-2008 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.
;
; ***************************************************************************
; See http://www.FreeRTOS.org for documentation, latest information, license
; and contact details. Please ensure to read the configuration and relevant
; port sections of the online documentation.
; ***************************************************************************
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
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