/* 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. *************************************************************************** *************************************************************************** * * * SAVE TIME AND MONEY! We can port FreeRTOS.org to your own hardware, * * and even write all or part of your application on your behalf. * * See http://www.OpenRTOS.com for details of the services we provide to * * expedite your project. * * * *************************************************************************** *************************************************************************** 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. */ /* High speed timer test as described in main.c. */ /* Scheduler includes. */ #include "FreeRTOS.h" /* The maximum value the 16bit timer can contain. */ #define timerMAX_COUNT 0xffff /* The timer 2 interrupt handler. */ void __attribute__( (interrupt(ipl0), vector(_TIMER_2_VECTOR))) vT2InterruptWrapper( void ); /*-----------------------------------------------------------*/ /* Incremented every 20,000 interrupts, so should count in seconds. */ unsigned portLONG ulHighFrequencyTimerInterrupts = 0; /* The frequency at which the timer is interrupting. */ static unsigned portLONG ulFrequencyHz; /*-----------------------------------------------------------*/ void vSetupTimerTest( unsigned portSHORT usFrequencyHz ) { /* Remember the frequency so it can be used from the ISR. */ ulFrequencyHz = ( unsigned portLONG ) usFrequencyHz; /* T2 is used to generate interrupts above the kernel and max syscall interrupt priority. */ T2CON = 0; TMR2 = 0; /* Timer 2 is going to interrupt at usFrequencyHz Hz. */ PR2 = ( unsigned portSHORT ) ( ( configPERIPHERAL_CLOCK_HZ / ( unsigned portLONG ) usFrequencyHz ) - 1 ); /* Setup timer 2 interrupt priority to be above the kernel priority so the timer jitter is not effected by the kernel activity. */ ConfigIntTimer2( T2_INT_ON | ( configMAX_SYSCALL_INTERRUPT_PRIORITY + 1 ) ); /* Clear the interrupt as a starting condition. */ IFS0bits.T2IF = 0; /* Enable the interrupt. */ IEC0bits.T2IE = 1; /* Start the timer. */ T2CONbits.TON = 1; } /*-----------------------------------------------------------*/ void vT2InterruptHandler( void ) { static unsigned portLONG ulCalls = 0; ++ulCalls; if( ulCalls >= ulFrequencyHz ) { /* Increment the count that will be shown on the LCD. The increment occurs once every 20,000 interrupts so ulHighFrequencyTimerInterrupts should count in seconds. */ ulHighFrequencyTimerInterrupts++; ulCalls = 0; } /* Clear the timer interrupt. */ IFS0bits.T2IF = 0; }