flash.c

RF tranceiver MSP430F1611+CC2420 with FreeRTOS

/*
	FreeRTOS V4.0.1 - Copyright (C) 2003-2006 Richard Barry.

	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 as published by
	the Free Software Foundation; either version 2 of the License, or
	(at your option) any later version.

	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
	along with FreeRTOS; 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, 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.
	***************************************************************************
*/

/**
 * This version of flash .c is for use on systems that have limited stack space
 * and no display facilities.  The complete version can be found in the 
 * Demo/Common/Full directory.
 * 
 * Three tasks are created, each of which flash an LED at a different rate.  The first 
 * LED flashes every 200ms, the second every 400ms, the third every 600ms.
 *
 * The LED flash tasks provide instant visual feedback.  They show that the scheduler 
 * is still operational.
 *
 * The PC port uses the standard parallel port for outputs, the Flashlite 186 port 
 * uses IO port F and the AVR port port B.
 *
 */

/*
Changes from V2.0.0

	+ Delay periods are now specified using variables and constants of
	  portTickType rather than unsigned portLONG.

Changes from V2.5.5

	+ Calls to vTaskDelay() have been replaced with vTaskDelayUntil().

*/

#include <stdlib.h>

/* Scheduler include files. */
#include "..\..\..\Os\include\FreeRTOS.h"
#include "..\..\..\Os\include\task.h"

/* Demo task include files. */
#include "..\include\flash.h"

#define ledSTACK_SIZE		configMINIMAL_STACK_SIZE
#define ledNUMBER_OF_LEDS	( 1 )
#define mainON_BOARD_LED_BIT	( ( unsigned portCHAR ) 0x01 )
#define ledFLASH_RATE_BASE	( ( portTickType ) 2000 )

/* Toggle the single genuine built in LED. */
static void prvToggleOnBoardLED( void );

/* The task that is created three times. */
static portTASK_FUNCTION_PROTO( vLEDFlashTask, pvParameters );

/*-----------------------------------------------------------*/

void vStartLEDFlashTask( unsigned portBASE_TYPE uxPriority )
{
signed portBASE_TYPE xLEDTask;

	/* Create the three tasks. */
	for( xLEDTask = 0; xLEDTask < ledNUMBER_OF_LEDS; ++xLEDTask )
	{
		/* Spawn the task. */
		xTaskCreate( vLEDFlashTask, ( const signed portCHAR * const ) "LED", ledSTACK_SIZE, NULL, uxPriority, ( xTaskHandle * ) NULL );
	}
}
/*-----------------------------------------------------------*/

static portTASK_FUNCTION( vLEDFlashTask, pvParameters )
{
portTickType xFlashRate, xLastFlashTime, xCurrentTime;

	/* The parameters are not used. */
	( void ) pvParameters;



	xFlashRate = ledFLASH_RATE_BASE;

	/* We need to initialise xLastFlashTime prior to the first call to 
	vTaskDelayUntil(). */
	xLastFlashTime = xTaskGetTickCount();



 	for( ; ; )
	{
		/* Delay for half the flash period then turn the LED on. */
//	vTaskDelayUntil( &xLastFlashTime, xFlashRate );
        volatile unsigned int i;
        vTaskDelay( xFlashRate );
        
        xCurrentTime = xTaskGetTickCount();
        xLastFlashTime = xCurrentTime + xFlashRate;
        
        
                while ( xCurrentTime < xLastFlashTime )
                {
                  xCurrentTime = xTaskGetTickCount();
                  
                  prvToggleOnBoardLED();                          // Toggle P1.0 using exclusive-OR
                  i = 50000;                                       // Delay
                  do (i--);
                  while (i != 0); 
                }
         }
}
/*-----------------------------------------------------------*/

static void prvToggleOnBoardLED( void )
{
static unsigned portSHORT sState = pdFALSE;

	/* Toggle the state of the single genuine on board LED. */
	if( sState )	
	{
		P6OUT |= mainON_BOARD_LED_BIT;
	}
	else
	{
		P6OUT &= ~mainON_BOARD_LED_BIT;
	}

	sState = !sState;
}
/*-----------------------------------------------------------*/