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|
;/*
; FreeRTOS V7.6.0 - Copyright (C) 2013 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.
;*/
#include "FreeRTOSConfig.h"
; Variables used by scheduler
;------------------------------------------------------------------------------
EXTERN pxCurrentTCB
EXTERN usCriticalNesting
;------------------------------------------------------------------------------
; portSAVE_CONTEXT MACRO
; Saves the context of the general purpose registers, CS and ES (only in far
; memory mode) registers the usCriticalNesting Value and the Stack Pointer
; of the active Task onto the task stack
;------------------------------------------------------------------------------
portSAVE_CONTEXT MACRO
PUSH AX ; Save AX Register to stack.
PUSH HL
#if __DATA_MODEL__ == __DATA_MODEL_FAR__
MOV A, CS ; Save CS register.
XCH A, X
MOV A, ES ; Save ES register.
PUSH AX
#else
MOV A, CS ; Save CS register.
PUSH AX
#endif
PUSH DE ; Save the remaining general purpose registers.
PUSH BC
MOVW AX, usCriticalNesting ; Save the usCriticalNesting value.
PUSH AX
MOVW AX, pxCurrentTCB ; Save the Stack pointer.
MOVW HL, AX
MOVW AX, SP
MOVW [HL], AX
ENDM
;------------------------------------------------------------------------------
;------------------------------------------------------------------------------
; portRESTORE_CONTEXT MACRO
; Restores the task Stack Pointer then use this to restore usCriticalNesting,
; general purpose registers and the CS and ES (only in far memory mode)
; of the selected task from the task stack
;------------------------------------------------------------------------------
portRESTORE_CONTEXT MACRO
MOVW AX, pxCurrentTCB ; Restore the Stack pointer.
MOVW HL, AX
MOVW AX, [HL]
MOVW SP, AX
POP AX ; Restore usCriticalNesting value.
MOVW usCriticalNesting, AX
POP BC ; Restore the necessary general purpose registers.
POP DE
#if __DATA_MODEL__ == __DATA_MODEL_FAR__
POP AX ; Restore the ES register.
MOV ES, A
XCH A, X ; Restore the CS register.
MOV CS, A
#else
POP AX
MOV CS, A ; Restore CS register.
#endif
POP HL ; Restore general purpose register HL.
POP AX ; Restore AX.
ENDM
;------------------------------------------------------------------------------
|
