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Diffstat (limited to 'FreeRTOS/Demo/AVR_Dx_MPLAB.X/main_blinky.c')
-rw-r--r-- | FreeRTOS/Demo/AVR_Dx_MPLAB.X/main_blinky.c | 176 |
1 files changed, 176 insertions, 0 deletions
diff --git a/FreeRTOS/Demo/AVR_Dx_MPLAB.X/main_blinky.c b/FreeRTOS/Demo/AVR_Dx_MPLAB.X/main_blinky.c new file mode 100644 index 000000000..99e156b0f --- /dev/null +++ b/FreeRTOS/Demo/AVR_Dx_MPLAB.X/main_blinky.c @@ -0,0 +1,176 @@ +/* + * FreeRTOS Kernel V10.3.1 + * 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! + */ + +/****************************************************************************** + * + * main_blinky() creates one queue, and two tasks. It then starts the + * scheduler. + * + * The Queue Send Task: + * The queue send task is implemented by the prvQueueSendTask() function in + * this file. prvQueueSendTask() sits in a loop that causes it to repeatedly + * block for 200 milliseconds, before sending the value 100 to the queue that + * was created within main_blinky(). Once the value is sent, the task loops + * back around to block for another 200 milliseconds...and so on. + * + * The Queue Receive Task: + * The queue receive task is implemented by the prvQueueReceiveTask() function + * in this file. prvQueueReceiveTask() sits in a loop where it repeatedly + * blocks on attempts to read data from the queue that was created within + * main_blinky(). When data is received, the task checks the value of the + * data, and if the value equals the expected 100, toggles an LED. The 'block + * time' parameter passed to the queue receive function specifies that the + * task should be held in the Blocked state indefinitely to wait for data to + * be available on the queue. The queue receive task will only leave the + * Blocked state when the queue send task writes to the queue. As the queue + * send task writes to the queue every 200 milliseconds, the queue receive + * task leaves the Blocked state every 200 milliseconds, and therefore toggles + * the LED every 200 milliseconds. + */ + +#include <avr/io.h> + +/* Scheduler include files. */ +#include "FreeRTOS.h" +#include "task.h" +#include "semphr.h" + +/* Priorities at which the tasks are created. */ +#define mainQUEUE_RECEIVE_TASK_PRIORITY ( tskIDLE_PRIORITY + 2 ) +#define mainQUEUE_SEND_TASK_PRIORITY ( tskIDLE_PRIORITY + 1 ) + +/* The rate at which data is sent to the queue. The 200ms value is converted +to ticks using the portTICK_PERIOD_MS constant. */ +#define mainQUEUE_SEND_FREQUENCY_MS ( 200 / portTICK_PERIOD_MS ) + +/* The number of items the queue can hold. This is 1 as the receive task +will remove items as they are added, meaning the send task should always find +the queue empty. */ +#define mainQUEUE_LENGTH ( 1 ) + +/*-----------------------------------------------------------*/ + +/* + * The tasks as described in the comments at the top of this file. + */ +static void prvQueueReceiveTask( void *pvParameters ); +static void prvQueueSendTask( void *pvParameters ); + +/*-----------------------------------------------------------*/ + +/* The queue used by both tasks. */ +static QueueHandle_t xQueue = NULL; + +void main_blinky( void ) +{ + /* Create the queue. */ + xQueue = xQueueCreate( mainQUEUE_LENGTH, sizeof( uint32_t ) ); + + if( xQueue != NULL ) + { + /* Start the two tasks as described in the comments at the top of this + file. */ + xTaskCreate( prvQueueReceiveTask, /* The function that implements the task. */ + "Rx", /* The text name assigned to the task - for debug only as it is not used by the kernel. */ + configMINIMAL_STACK_SIZE, /* The size of the stack to allocate to the task. */ + NULL, /* The parameter passed to the task - not used in this case. */ + mainQUEUE_RECEIVE_TASK_PRIORITY, /* The priority assigned to the task. */ + NULL ); /* The task handle is not required, so NULL is passed. */ + + xTaskCreate( prvQueueSendTask, "TX", configMINIMAL_STACK_SIZE, NULL, mainQUEUE_SEND_TASK_PRIORITY, NULL ); + + /* Start the tasks and timer running. */ + vTaskStartScheduler(); + } + + /* If all is well, the scheduler will now be running, and the following + line will never be reached. If the following line does execute, then + there was either insufficient FreeRTOS heap memory available for the idle + and/or timer tasks to be created, or vTaskStartScheduler() was called from + User mode. See the memory management section on the FreeRTOS web site for + more details on the FreeRTOS heap http://www.freertos.org/a00111.html. The + mode from which main() is called is set in the C start up code and must be + a privileged mode (not user mode). */ + for( ;; ); +} + +void init_blinky( void ) +{ + /* Set PC6 as output. */ + PORTC.DIRSET = PIN6_bm; +} + +static void prvQueueSendTask( void *pvParameters ) +{ +TickType_t xNextWakeTime; +const unsigned long ulValueToSend = 100UL; + + /* Remove compiler warning about unused parameter. */ + ( void ) pvParameters; + + /* Initialise xNextWakeTime - this only needs to be done once. */ + xNextWakeTime = xTaskGetTickCount(); + + for( ;; ) + { + /* Place this task in the blocked state until it is time to run again. */ + vTaskDelayUntil( &xNextWakeTime, mainQUEUE_SEND_FREQUENCY_MS ); + + /* Send to the queue - causing the queue receive task to unblock and + toggle the LED. 0 is used as the block time so the sending operation + will not block - it shouldn't need to block as the queue should always + be empty at this point in the code. */ + xQueueSend( xQueue, &ulValueToSend, 0U ); + } +} +/*-----------------------------------------------------------*/ + +static void prvQueueReceiveTask( void *pvParameters ) +{ +unsigned long ulReceivedValue; +const unsigned long ulExpectedValue = 100UL; + + /* Remove compiler warning about unused parameter. */ + ( void ) pvParameters; + + for( ;; ) + { + /* Wait until something arrives in the queue - this task will block + indefinitely provided INCLUDE_vTaskSuspend is set to 1 in + FreeRTOSConfig.h. */ + xQueueReceive( xQueue, &ulReceivedValue, portMAX_DELAY ); + + /* To get here something must have been received from the queue, but + is it the expected value? If it is, toggle the LED. */ + if( ulReceivedValue == ulExpectedValue ) + { + /* Toggle LED on pin PC6. */ + PORTC.OUTTGL |= PIN6_bm; + ulReceivedValue = 0U; + } + } +} |