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			61 lines
		
	
	
		
			2.5 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
			
		
		
	
	
			61 lines
		
	
	
		
			2.5 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
;/*
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; * FreeRTOS Kernel <DEVELOPMENT BRANCH>
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; * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
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; *
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; * SPDX-License-Identifier: MIT
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; *
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; * Permission is hereby granted, free of charge, to any person obtaining a copy of
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; * this software and associated documentation files (the "Software"), to deal in
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; * the Software without restriction, including without limitation the rights to
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; * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
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; * the Software, and to permit persons to whom the Software is furnished to do so,
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; * subject to the following conditions:
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; *
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; * The above copyright notice and this permission notice shall be included in all
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; * copies or substantial portions of the Software.
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; *
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; * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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; * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
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; * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
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; * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
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; * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
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; * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
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; *
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; * https://www.FreeRTOS.org
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; * https://github.com/FreeRTOS
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; *
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; */
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        RSEG ICODE:CODE
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        CODE32
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    EXTERN vTaskSwitchContext
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    PUBLIC vPortYieldProcessor
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    PUBLIC vPortStartFirstTask
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#include "ISR_Support.h"
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;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
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; Starting the first task is just a matter of restoring the context that
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; was created by pxPortInitialiseStack().
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;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
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vPortStartFirstTask:
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    portRESTORE_CONTEXT
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;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
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; Manual context switch function.  This is the SWI hander.
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;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
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vPortYieldProcessor:
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    ADD     LR, LR, #4          ; Add 4 to the LR to make the LR appear exactly
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                                ; as if the context was saved during and IRQ
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                                ; handler.
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    portSAVE_CONTEXT            ; Save the context of the current task...
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    LDR R0, =vTaskSwitchContext ; before selecting the next task to execute.
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    mov     lr, pc
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    BX R0
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    portRESTORE_CONTEXT         ; Restore the context of the selected task.
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    END
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