/* | |
FreeRTOS V9.0.1 - Copyright (C) 2017 Real Time Engineers Ltd. | |
All rights reserved | |
VISIT http://www.FreeRTOS.org TO ENSURE YOU ARE USING THE LATEST VERSION. | |
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. Full license text is available on the following | |
link: http://www.freertos.org/a00114.html | |
*************************************************************************** | |
* * | |
* FreeRTOS provides completely free yet professionally developed, * | |
* robust, strictly quality controlled, supported, and cross * | |
* platform software that is more than just the market leader, it * | |
* is the industry's de facto standard. * | |
* * | |
* Help yourself get started quickly while simultaneously helping * | |
* to support the FreeRTOS project by purchasing a FreeRTOS * | |
* tutorial book, reference manual, or both: * | |
* http://www.FreeRTOS.org/Documentation * | |
* * | |
*************************************************************************** | |
http://www.FreeRTOS.org/FAQHelp.html - Having a problem? Start by reading | |
the FAQ page "My application does not run, what could be wrong?". Have you | |
defined configASSERT()? | |
http://www.FreeRTOS.org/support - In return for receiving this top quality | |
embedded software for free we request you assist our global community by | |
participating in the support forum. | |
http://www.FreeRTOS.org/training - Investing in training allows your team to | |
be as productive as possible as early as possible. Now you can receive | |
FreeRTOS training directly from Richard Barry, CEO of Real Time Engineers | |
Ltd, and the world's leading authority on the world's leading RTOS. | |
http://www.FreeRTOS.org/plus - A selection of FreeRTOS ecosystem products, | |
including FreeRTOS+Trace - an indispensable productivity tool, a DOS | |
compatible FAT file system, and our tiny thread aware UDP/IP stack. | |
http://www.FreeRTOS.org/labs - Where new FreeRTOS products go to incubate. | |
Come and try FreeRTOS+TCP, our new open source TCP/IP stack for FreeRTOS. | |
http://www.OpenRTOS.com - Real Time Engineers ltd. license FreeRTOS to High | |
Integrity Systems ltd. to sell under the OpenRTOS brand. Low cost OpenRTOS | |
licenses offer ticketed support, indemnification and commercial middleware. | |
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. | |
1 tab == 4 spaces! | |
*/ | |
/* High speed timer test as described in main.c. */ | |
#include <device.h> | |
/* Scheduler includes. */ | |
#include "FreeRTOS.h" | |
/* The set frequency of the interrupt. Deviations from this are measured as | |
the jitter. */ | |
#define timerINTERRUPT_FREQUENCY ( ( unsigned short ) 20000 ) | |
/* The expected time between each of the timer interrupts - if the jitter was | |
zero. */ | |
#define timerEXPECTED_DIFFERENCE_VALUE ( configCPU_CLOCK_HZ / timerINTERRUPT_FREQUENCY ) | |
/* The number of interrupts to pass before we start looking at the jitter. */ | |
#define timerSETTLE_TIME 5 | |
/*---------------------------------------------------------------------------*/ | |
/* | |
* Configures the two timers used to perform the test. | |
*/ | |
void vSetupTimerTest( void ); | |
/* Interrupt handler in which the jitter is measured. */ | |
CY_ISR_PROTO(vTimer20KHzISR); | |
/* Stores the value of the maximum recorded jitter between interrupts. */ | |
volatile unsigned short usMaxJitter = 0; | |
/*---------------------------------------------------------------------------*/ | |
void vSetupTimerTest( void ) | |
{ | |
/* Install the ISR. */ | |
isrTimer_20KHz_TC_StartEx(vTimer20KHzISR); | |
} | |
/*---------------------------------------------------------------------------*/ | |
CY_ISR(vTimer20KHzISR) | |
{ | |
static unsigned short usLastCount = 0, usSettleCount = 0, usMaxDifference = 0; | |
unsigned short usThisCount, usDifference; | |
/* Capture the free running timer value as we enter the interrupt. */ | |
usThisCount = Timer_48MHz_ReadCounter(); | |
if( usSettleCount >= timerSETTLE_TIME ) | |
{ | |
/* What is the difference between the timer value in this interrupt | |
and the value from the last interrupt. Timer counts down. */ | |
usDifference = usLastCount + ~usThisCount + 1; | |
/* 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 > usMaxDifference ) | |
{ | |
usMaxDifference = usDifference; | |
/* Calculate the Jitter based on the difference we expect. */ | |
usMaxJitter = usMaxDifference - timerEXPECTED_DIFFERENCE_VALUE; | |
} | |
} | |
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; | |
} | |
/*---------------------------------------------------------------------------*/ |