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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.
; ***************************************************************************
;
;------------------------------------------------------------------------------
#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 configMEMORY_MODE == 1
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 configMEMORY_MODE == 1
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
;------------------------------------------------------------------------------
|
