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Update to V4.3.0 as described in http://www.FreeRTOS.org/History.txt

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Richard Barry 2007-06-05 09:44:58 +00:00
parent 45410fcd3a
commit 67d0d1ec3b
38 changed files with 1173 additions and 756 deletions
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Demo/dsPIC_MPLAB/timertest.c Normal file
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/*
FreeRTOS.org V4.3.0 - Copyright (C) 2003-2007 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.
Also see http://www.SafeRTOS.com for an IEC 61508 compliant version along
with commercial development and support options.
***************************************************************************
*/
/* High speed timer test as described in main.c. */
/* Scheduler includes. */
#include "FreeRTOS.h"
/* Demo includes. */
#include "partest.h"
/* The number of interrupts to pass before we start looking at the jitter. */
#define timerSETTLE_TIME 5
/* The maximum value the 16bit timer can contain. */
#define timerMAX_COUNT 0xffff
/*-----------------------------------------------------------*/
/*
* Measure the time between this interrupt and the previous interrupt to
* calculate the timing jitter. Remember the maximum value the jitter has
* ever been calculated to be.
*/
static void prvCalculateAndStoreJitter( void );
/*-----------------------------------------------------------*/
/* The maximum time (in processor clocks) between two consecutive timer
interrupts so far. */
unsigned portSHORT usMaxJitter = 0;
/*-----------------------------------------------------------*/
void vSetupTimerTest( unsigned portSHORT usFrequencyHz )
{
/* T2 is used to generate interrupts. T4 is used to provide an accurate
time measurement. */
T2CON = 0;
T4CON = 0;
TMR2 = 0;
TMR4 = 0;
/* Timer 2 is going to interrupt at usFrequencyHz Hz. */
PR2 = ( unsigned portSHORT ) ( configCPU_CLOCK_HZ / ( unsigned portLONG ) usFrequencyHz );
/* Timer 4 is going to free run from minimum to maximum value. */
PR4 = ( unsigned portSHORT ) timerMAX_COUNT;
/* Setup timer 2 interrupt priority to be above the kernel priority so
the timer jitter is not effected by the kernel activity. */
IPC1bits.T2IP = configKERNEL_INTERRUPT_PRIORITY + 1;
/* Clear the interrupt as a starting condition. */
IFS0bits.T2IF = 0;
/* Enable the interrupt. */
IEC0bits.T2IE = 1;
/* Start both timers. */
T2CONbits.TON = 1;
T4CONbits.TON = 1;
}
/*-----------------------------------------------------------*/
static void prvCalculateAndStoreJitter( void )
{
static unsigned portSHORT usLastCount = 0, usSettleCount = 0;
unsigned portSHORT usThisCount, usDifference;
/* Capture the timer value as we enter the interrupt. */
usThisCount = TMR4;
if( usSettleCount >= timerSETTLE_TIME )
{
/* What is the difference between the timer value in this interrupt
and the value from the last interrupt. */
usDifference = usThisCount - usLastCount;
/* Store the difference in the timer values if it is larger than the
currently stored largest value. The difference over and above the
expected difference will give the 'jitter' in the processing of these
interrupts. */
if( usDifference > usMaxJitter )
{
usMaxJitter = usDifference;
}
}
else
{
/* Don't bother storing any values for the first couple of
interrupts. */
usSettleCount++;
}
/* Remember what the timer value was this time through, so we can calculate
the difference the next time through. */
usLastCount = usThisCount;
}
/*-----------------------------------------------------------*/
void __attribute__((__interrupt__, auto_psv)) _T2Interrupt( void )
{
/* Work out the time between this and the previous interrupt. */
prvCalculateAndStoreJitter();
/* Clear the timer interrupt. */
IFS0bits.T2IF = 0;
}