MKMxxZxxACxx5 Bare Metal Software Drivers  R4.1.6
Reference Manual
PIT Triggered FreeRTOS Handler Task

This example shows use of the handler task. The handler task is waiting in blocked state for a notification from the Periodic Interrupt Timer (PIT) module's callback function. When the handler task is notified it toggles the LED connected on PTJ3 and after context switch is blocked again.

Source code:
#include "drivers.h"
#include "freertos.h"
/* PIT callback declarations */
void pit_callback (PIT_CALLBACK_TYPE type);
/* function including configuration of peripherals */
static void prvSetupHardware (void);
/* PIT interrupt handler task */
static void prvHandlerTask (void * pvParameters);
/* task notification handler */
TaskHandle_t xTaskToNotify = NULL;
void main (void)
{
prvSetupHardware ();
/* create task*/
xTaskCreate
(
prvHandlerTask, /* the function that implements the task */
"Handler Task", /* the text name assigned to the task */
configMINIMAL_STACK_SIZE, /* the size of the stack of the task */
NULL, /* the parameter passed to the task */
1, /* the priority assigned to the task */
NULL /* the task handle */
);
/* start the tasks and timer running including enabling all interrupts */
vTaskStartScheduler ();
/* this loop will never be reached */
while(1);
}
void prvSetupHardware( void ){
/* enable clocks to all on chip peripherals */
/* initialize led */
/* initialize PIT */
PIT_InstallCallback (PRI_LVL2, pit_callback);
PIT_Init (PIT0, CH0, PIT_CH_TMR_EN_CONFIG, 1000000);
}
static void prvHandlerTask (void *pvParameters)
{
xTaskToNotify = xTaskGetCurrentTaskHandle ();
for(;;)
{
/* task is blocked until gets notification */
ulTaskNotifyTake (pdTRUE, portMAX_DELAY);
GPIO_Tgl (GPIOE, PIN5);
}
}
void pit_callback (PIT_CALLBACK_TYPE type)
{
if (type == PIT0CH0_CALLBACK)
{
portBASE_TYPE xHigherPriorityTaskWoken = pdFALSE;
/* test if the xTaskToNotify isn't NULL. */
configASSERT (xTaskToNotify != NULL);
/* notify handler task */
vTaskNotifyGiveFromISR (xTaskToNotify, &xHigherPriorityTaskWoken);
/* switch task */
portEND_SWITCHING_ISR (xHigherPriorityTaskWoken);
}
}
Freertos_cfg.h:
/*
FreeRTOS V8.2.1 - Copyright (C) 2015 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!
*/
#ifndef FREERTOS_CONFIG_H
#define FREERTOS_CONFIG_H
/*-----------------------------------------------------------
* Application specific definitions.
*
* These definitions should be adjusted for your particular hardware and
* application requirements.
*
* THESE PARAMETERS ARE DESCRIBED WITHIN THE 'CONFIGURATION' SECTION OF THE
* FreeRTOS API DOCUMENTATION AVAILABLE ON THE FreeRTOS.org WEB SITE.
*
* See http://www.freertos.org/a00110.html.
*----------------------------------------------------------*/
/* Select features and configuration. */
#define configUSE_PREEMPTION 1
#define configUSE_PORT_OPTIMISED_TASK_SELECTION 0
#define configUSE_TICKLESS_IDLE 0
#define configCPU_CLOCK_HZ 2000000
#define configTICK_RATE_HZ 250
#define configMAX_PRIORITIES 5
#define configMINIMAL_STACK_SIZE 128
#define configMAX_TASK_NAME_LEN 16
#define configUSE_16_BIT_TICKS 0
#define configIDLE_SHOULD_YIELD 1
#define configUSE_TASK_NOTIFICATIONS 1
#define configUSE_MUTEXES 0
#define configUSE_RECURSIVE_MUTEXES 0
#define configUSE_COUNTING_SEMAPHORES 0
#define configUSE_ALTERNATIVE_API 0 /* Deprecated! */
#define configQUEUE_REGISTRY_SIZE 10
#define configUSE_QUEUE_SETS 0
#define configUSE_TIME_SLICING 0
#define configUSE_NEWLIB_REENTRANT 0
#define configENABLE_BACKWARD_COMPATIBILITY 0
#define configNUM_THREAD_LOCAL_STORAGE_POINTERS 5
/* Select one of the following heap type. */
#define configTOTAL_HEAP_SIZE 12000
#define configUSE_HEAP_1 1
#define configUSE_HEAP_2 0
#define configUSE_HEAP_3 0
#define configUSE_HEAP_4 0
#define configUSE_HEAP_5 0
/* Hook function related definitions. */
#define configUSE_IDLE_HOOK 0
#define configUSE_TICK_HOOK 0
#define configCHECK_FOR_STACK_OVERFLOW 0
#define configUSE_MALLOC_FAILED_HOOK 0
/* Run time and task stats gathering related definitions. */
#define configGENERATE_RUN_TIME_STATS 0
#define configUSE_TRACE_FACILITY 0
#define configUSE_STATS_FORMATTING_FUNCTIONS 0
/* Co-routine related definitions. */
#define configUSE_CO_ROUTINES 0
#define configMAX_CO_ROUTINE_PRIORITIES 1
/* Software timer related definitions. */
#define configUSE_TIMERS 1
#define configTIMER_TASK_PRIORITY 3
#define configTIMER_QUEUE_LENGTH 10
#define configTIMER_TASK_STACK_DEPTH configMINIMAL_STACK_SIZE
/* Define to trap errors during development. */
#define configASSERT(x) if((x)==0) { taskDISABLE_INTERRUPTS(); for( ;; ); }
/* Optional functions - most linkers will remove unused functions anyway. */
#define INCLUDE_vTaskPrioritySet 1
#define INCLUDE_uxTaskPriorityGet 1
#define INCLUDE_vTaskDelete 0
#define INCLUDE_vTaskSuspend 1
#define INCLUDE_xResumeFromISR 1
#define INCLUDE_vTaskDelayUntil 1
#define INCLUDE_vTaskDelay 1
#define INCLUDE_xTaskGetSchedulerState 1
#define INCLUDE_xTaskGetCurrentTaskHandle 1
#define INCLUDE_uxTaskGetStackHighWaterMark 0
#define INCLUDE_xTaskGetIdleTaskHandle 0
#define INCLUDE_xTimerGetTimerDaemonTaskHandle 0
#define INCLUDE_pcTaskGetTaskName 0
#define INCLUDE_eTaskGetState 0
#define INCLUDE_xEventGroupSetBitFromISR 1
#define INCLUDE_xTimerPendFunctionCall 1
#endif /* FREERTOS_CONFIG_H */
Toolchain support:
IAR EWARM 7.40.7CodeWarrior 10.6KEIL uVision 5.15CrossWorks 3.6ATOLLIC TrueStudio 5.3.0Kinetis Design Studio 3.0.0