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/*
FreeRTOS.org V5.2.0 - Copyright (C) 2003-2009 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 (version 2) as published
by the Free Software Foundation and modified by the FreeRTOS exception.
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 is included to allow you 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.
***************************************************************************
* *
* Get the FreeRTOS eBook! See http://www.FreeRTOS.org/Documentation *
* *
* This is a concise, step by step, 'hands on' guide that describes both *
* general multitasking concepts and FreeRTOS specifics. It presents and *
* explains numerous examples that are written using the FreeRTOS API. *
* Full source code for all the examples is provided in an accompanying *
* .zip file. *
* *
***************************************************************************
1 tab == 4 spaces!
Please ensure to read the configuration and relevant port sections of the
online documentation.
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.
*/
.global _vPortYield
.extern _vTaskSwitchContext
.extern uxCriticalNesting
_vPortYield:
PUSH SR /* Save the SR used by the task.... */
PUSH W0 /* ....then disable interrupts. */
MOV #32, W0
MOV W0, SR
PUSH W1 /* Save registers to the stack. */
PUSH.D W2
PUSH.D W4
PUSH.D W6
PUSH.D W8
PUSH.D W10
PUSH.D W12
PUSH W14
PUSH RCOUNT
PUSH TBLPAG
PUSH ACCAL
PUSH ACCAH
PUSH ACCAU
PUSH ACCBL
PUSH ACCBH
PUSH ACCBU
PUSH DCOUNT
PUSH DOSTARTL
PUSH DOSTARTH
PUSH DOENDL
PUSH DOENDH
PUSH CORCON
PUSH PSVPAG
MOV _uxCriticalNesting, W0 /* Save the critical nesting counter for the task. */
PUSH W0
MOV _pxCurrentTCB, W0 /* Save the new top of stack into the TCB. */
MOV W15, [W0]
call _vTaskSwitchContext
MOV _pxCurrentTCB, W0 /* Restore the stack pointer for the task. */
MOV [W0], W15
POP W0 /* Restore the critical nesting counter for the task. */
MOV W0, _uxCriticalNesting
POP PSVPAG
POP CORCON
POP DOENDH
POP DOENDL
POP DOSTARTH
POP DOSTARTL
POP DCOUNT
POP ACCBU
POP ACCBH
POP ACCBL
POP ACCAU
POP ACCAH
POP ACCAL
POP TBLPAG
POP RCOUNT /* Restore the registers from the stack. */
POP W14
POP.D W12
POP.D W10
POP.D W8
POP.D W6
POP.D W4
POP.D W2
POP.D W0
POP SR
return
.end
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