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/*
* FreeRTOS Kernel V10.3.0
* Copyright (C) 2020 Amazon.com, Inc. or its affiliates. All Rights Reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of
* this software and associated documentation files (the "Software"), to deal in
* the Software without restriction, including without limitation the rights to
* use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
* the Software, and to permit persons to whom the Software is furnished to do so,
* subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all
* copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
* FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
* COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
* IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*
* http://www.FreeRTOS.org
* http://aws.amazon.com/freertos
*
* 1 tab == 4 spaces!
*/
/*
* THIS DEMO APPLICATION REQUIRES A LOOPBACK CONNECTOR TO BE FITTED TO THE PIC
* USART PORT - connect pin 2 to pin 3 on J2.
*
* Instead of the normal single demo application, the PIC18F demo is split
* into several smaller programs of which this is the third. This enables the
* demo's to be executed on the RAM limited 40 pin devices. The 64 and 80 pin
* devices require a more costly development platform and are not so readily
* available.
*
* The RTOSDemo3 project is configured for a PIC18F452 device. Main3.c starts
* 5 tasks (including the idle task).
*
* The first task repeatedly transmits a string of characters on the PIC USART
* port. The second task receives the characters, checking that the correct
* sequence is maintained (i.e. what is transmitted is identical to that
* received). Each transmitted and each received character causes an LED to
* flash. See demo/common/minimal/comtest. c for more information.
*
* The third task continuously performs a 32 bit calculation. This is a good
* test of the context switch mechanism as the 8 bit architecture requires
* the use of several file registers to perform the 32 bit operations. See
* demo/common/minimal/integer. c for more information.
*
* The third task is the check task. This periodically checks that the other
* tasks are still running and have not experienced any errors. If no errors
* have been reported by either the comms or integer tasks an LED is flashed
* with a frequency mainNO_ERROR_CHECK_PERIOD. If an error is discovered the
* frequency is increased to mainERROR_FLASH_RATE.
*
* The check task also provides a visual indication of a system reset by
* flashing the one remaining LED (mainRESET_LED) when it starts. After
* this initial flash mainRESET_LED should remain off.
*
* http://www.FreeRTOS.org contains important information on the use of the
* PIC18F port.
*/
/*
Changes from V2.0.0
+ Delay periods are now specified using variables and constants of
TickType_t rather than unsigned long.
*/
/* Scheduler include files. */
#include "FreeRTOS.h"
#include "task.h"
/* Demo app include files. */
#include "partest.h"
#include "serial.h"
#include "comtest.h"
#include "integer.h"
/* Priority definitions for the LED tasks. Other tasks just use the idle
priority. */
#define mainCOMM_TEST_PRIORITY ( tskIDLE_PRIORITY + ( unsigned portBASE_TYPE ) 2 )
#define mainCHECK_TASK_PRIORITY ( tskIDLE_PRIORITY + ( unsigned portBASE_TYPE ) 3 )
/* The period between executions of the check task before and after an error
has been discovered. If an error has been discovered the check task runs
more frequently - increasing the LED flash rate. */
#define mainNO_ERROR_CHECK_PERIOD ( ( TickType_t ) 1000 / portTICK_PERIOD_MS )
#define mainERROR_CHECK_PERIOD ( ( TickType_t ) 100 / portTICK_PERIOD_MS )
/* The period for which mainRESET_LED remain on every reset. */
#define mainRESET_LED_PERIOD ( ( TickType_t ) 500 / portTICK_PERIOD_MS )
/* The LED that is toggled whenever a character is transmitted.
mainCOMM_TX_RX_LED + 1 will be toggled every time a character is received. */
#define mainCOMM_TX_RX_LED ( ( unsigned portBASE_TYPE ) 2 )
/* The LED that is flashed by the check task at a rate that indicates the
error status. */
#define mainCHECK_TASK_LED ( ( unsigned portBASE_TYPE ) 1 )
/* The LED that is flashed once upon every reset. */
#define mainRESET_LED ( ( unsigned portBASE_TYPE ) 0 )
/* Constants required for the communications. */
#define mainCOMMS_QUEUE_LENGTH ( ( unsigned portBASE_TYPE ) 5 )
#define mainBAUD_RATE ( ( unsigned long ) 57600 )
/*-----------------------------------------------------------*/
/*
* Task function which periodically checks the other tasks for errors. Flashes
* an LED at a rate that indicates whether an error has ever been detected.
*/
static void vErrorChecks( void *pvParameters );
/*-----------------------------------------------------------*/
/* Creates the tasks, then starts the scheduler. */
void main( void )
{
/* Initialise the required hardware. */
vParTestInitialise();
/* Initialise the block memory allocator. */
vPortInitialiseBlocks();
/* Start the standard comtest tasks as defined in demo/common/minimal. */
vAltStartComTestTasks( mainCOMM_TEST_PRIORITY, mainBAUD_RATE, mainCOMM_TX_RX_LED );
/* Start the standard 32bit calculation task as defined in
demo/common/minimal. */
vStartIntegerMathTasks( tskIDLE_PRIORITY );
/* Start the check task defined in this file. */
xTaskCreate( vErrorChecks, "Check", configMINIMAL_STACK_SIZE, NULL, mainCHECK_TASK_PRIORITY, NULL );
/* Start the scheduler. This will never return. */
vTaskStartScheduler();
}
/*-----------------------------------------------------------*/
static void vErrorChecks( void *pvParameters )
{
TickType_t xDelayTime = mainNO_ERROR_CHECK_PERIOD;
volatile unsigned long ulDummy = 3UL;
/* Toggle the LED so we can see when a reset occurs. */
vParTestSetLED( mainRESET_LED, pdTRUE );
vTaskDelay( mainRESET_LED_PERIOD );
vParTestSetLED( mainRESET_LED, pdFALSE );
/* Cycle for ever, delaying then checking all the other tasks are still
operating without error. */
for( ;; )
{
/* Wait until it is time to check the other tasks. */
vTaskDelay( xDelayTime );
/* Perform an integer calculation - just to ensure the registers
get used. The result is not important. */
ulDummy *= 3UL;
/* Check all the other tasks are running, and running without ever
having an error. The delay period is lowered if an error is reported,
causing the LED to flash at a higher rate. */
if( xAreIntegerMathsTaskStillRunning() == pdFALSE )
{
xDelayTime = mainERROR_CHECK_PERIOD;
}
if( xAreComTestTasksStillRunning() == pdFALSE )
{
xDelayTime = mainERROR_CHECK_PERIOD;
}
/* Flash the LED for visual feedback. The rate of the flash will
indicate the health of the system. */
vParTestToggleLED( mainCHECK_TASK_LED );
}
}
/*-----------------------------------------------------------*/
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