/* | |
FreeRTOS V7.4.1 - Copyright (C) 2013 Real Time Engineers Ltd. | |
FEATURES AND PORTS ARE ADDED TO FREERTOS ALL THE TIME. PLEASE VISIT | |
http://www.FreeRTOS.org TO ENSURE YOU ARE USING THE LATEST VERSION. | |
*************************************************************************** | |
* * | |
* 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 Real Time Engineers Ltd., contact details for whom are available | |
on the FreeRTOS WEB site. | |
1 tab == 4 spaces! | |
*************************************************************************** | |
* * | |
* Having a problem? Start by reading the FAQ "My application does * | |
* not run, what could be wrong?" * | |
* * | |
* http://www.FreeRTOS.org/FAQHelp.html * | |
* * | |
*************************************************************************** | |
http://www.FreeRTOS.org - Documentation, books, training, latest versions, | |
license and Real Time Engineers Ltd. contact details. | |
http://www.FreeRTOS.org/plus - A selection of FreeRTOS ecosystem products, | |
including FreeRTOS+Trace - an indispensable productivity tool, and our new | |
fully thread aware and reentrant UDP/IP stack. | |
http://www.OpenRTOS.com - Real Time Engineers ltd license FreeRTOS to High | |
Integrity Systems, who sell the code with commercial support, | |
indemnification and middleware, under the OpenRTOS brand. | |
http://www.SafeRTOS.com - High Integrity Systems also provide a safety | |
engineered and independently SIL3 certified version for use in safety and | |
mission critical applications that require provable dependability. | |
*/ | |
/* Scheduler includes. */ | |
#include "FreeRTOS.h" | |
#include "task.h" | |
/*----------------------------------------------------------- | |
* Implementation of functions defined in portable.h for the MSP430 port. | |
*----------------------------------------------------------*/ | |
/* Constants required for hardware setup. The tick ISR runs off the ACLK, | |
not the MCLK. */ | |
#define portACLK_FREQUENCY_HZ ( ( portTickType ) 32768 ) | |
#define portINITIAL_CRITICAL_NESTING ( ( unsigned short ) 10 ) | |
#define portFLAGS_INT_ENABLED ( ( portSTACK_TYPE ) 0x08 ) | |
/* We require the address of the pxCurrentTCB variable, but don't want to know | |
any details of its type. */ | |
typedef void tskTCB; | |
extern volatile tskTCB * volatile pxCurrentTCB; | |
/* Each task maintains a count of the critical section nesting depth. Each | |
time a critical section is entered the count is incremented. Each time a | |
critical section is exited the count is decremented - with interrupts only | |
being re-enabled if the count is zero. | |
usCriticalNesting will get set to zero when the scheduler starts, but must | |
not be initialised to zero as this will cause problems during the startup | |
sequence. */ | |
volatile unsigned short usCriticalNesting = portINITIAL_CRITICAL_NESTING; | |
/*-----------------------------------------------------------*/ | |
/* | |
* Sets up the periodic ISR used for the RTOS tick. This uses timer 0, but | |
* could have alternatively used the watchdog timer or timer 1. | |
*/ | |
void vPortSetupTimerInterrupt( void ); | |
/*-----------------------------------------------------------*/ | |
/* | |
* Initialise the stack of a task to look exactly as if a call to | |
* portSAVE_CONTEXT had been called. | |
* | |
* See the header file portable.h. | |
*/ | |
portSTACK_TYPE *pxPortInitialiseStack( portSTACK_TYPE *pxTopOfStack, pdTASK_CODE pxCode, void *pvParameters ) | |
{ | |
/* | |
Place a few bytes of known values on the bottom of the stack. | |
This is just useful for debugging and can be included if required. | |
*pxTopOfStack = ( portSTACK_TYPE ) 0x1111; | |
pxTopOfStack--; | |
*pxTopOfStack = ( portSTACK_TYPE ) 0x2222; | |
pxTopOfStack--; | |
*pxTopOfStack = ( portSTACK_TYPE ) 0x3333; | |
pxTopOfStack--; | |
*/ | |
/* The msp430 automatically pushes the PC then SR onto the stack before | |
executing an ISR. We want the stack to look just as if this has happened | |
so place a pointer to the start of the task on the stack first - followed | |
by the flags we want the task to use when it starts up. */ | |
*pxTopOfStack = ( portSTACK_TYPE ) pxCode; | |
pxTopOfStack--; | |
*pxTopOfStack = portFLAGS_INT_ENABLED; | |
pxTopOfStack--; | |
/* Next the general purpose registers. */ | |
*pxTopOfStack = ( portSTACK_TYPE ) 0x4444; | |
pxTopOfStack--; | |
*pxTopOfStack = ( portSTACK_TYPE ) 0x5555; | |
pxTopOfStack--; | |
*pxTopOfStack = ( portSTACK_TYPE ) 0x6666; | |
pxTopOfStack--; | |
*pxTopOfStack = ( portSTACK_TYPE ) 0x7777; | |
pxTopOfStack--; | |
*pxTopOfStack = ( portSTACK_TYPE ) 0x8888; | |
pxTopOfStack--; | |
*pxTopOfStack = ( portSTACK_TYPE ) 0x9999; | |
pxTopOfStack--; | |
*pxTopOfStack = ( portSTACK_TYPE ) 0xaaaa; | |
pxTopOfStack--; | |
*pxTopOfStack = ( portSTACK_TYPE ) 0xbbbb; | |
pxTopOfStack--; | |
/* When the task starts is will expect to find the function parameter in | |
R15. */ | |
*pxTopOfStack = ( portSTACK_TYPE ) pvParameters; | |
pxTopOfStack--; | |
*pxTopOfStack = ( portSTACK_TYPE ) 0xdddd; | |
pxTopOfStack--; | |
*pxTopOfStack = ( portSTACK_TYPE ) 0xeeee; | |
pxTopOfStack--; | |
*pxTopOfStack = ( portSTACK_TYPE ) 0xffff; | |
pxTopOfStack--; | |
/* A variable is used to keep track of the critical section nesting. | |
This variable has to be stored as part of the task context and is | |
initially set to zero. */ | |
*pxTopOfStack = ( portSTACK_TYPE ) portNO_CRITICAL_SECTION_NESTING; | |
/* Return a pointer to the top of the stack we have generated so this can | |
be stored in the task control block for the task. */ | |
return pxTopOfStack; | |
} | |
/*-----------------------------------------------------------*/ | |
void vPortEndScheduler( void ) | |
{ | |
/* It is unlikely that the MSP430 port will get stopped. If required simply | |
disable the tick interrupt here. */ | |
} | |
/*-----------------------------------------------------------*/ | |
/* | |
* Hardware initialisation to generate the RTOS tick. This uses timer 0 | |
* but could alternatively use the watchdog timer or timer 1. | |
*/ | |
void vPortSetupTimerInterrupt( void ) | |
{ | |
/* Ensure the timer is stopped. */ | |
TACTL = 0; | |
/* Run the timer of the ACLK. */ | |
TACTL = TASSEL_1; | |
/* Clear everything to start with. */ | |
TACTL |= TACLR; | |
/* Set the compare match value according to the tick rate we want. */ | |
TACCR0 = portACLK_FREQUENCY_HZ / configTICK_RATE_HZ; | |
/* Enable the interrupts. */ | |
TACCTL0 = CCIE; | |
/* Start up clean. */ | |
TACTL |= TACLR; | |
/* Up mode. */ | |
TACTL |= MC_1; | |
} | |
/*-----------------------------------------------------------*/ | |