/*\r
- FreeRTOS V8.2.3 - Copyright (C) 2015 Real Time Engineers Ltd.\r
+ FreeRTOS V9.0.0rc1 - Copyright (C) 2016 Real Time Engineers Ltd.\r
All rights reserved\r
\r
VISIT http://www.FreeRTOS.org TO ENSURE YOU ARE USING THE LATEST VERSION.\r
*/\r
\r
/******************************************************************************\r
- * NOTE 1: Do not expect to get real time behaviour from the Win32 port or this\r
- * demo application. It is provided as a convenient development and\r
- * demonstration test bed only. Windows will not be running the FreeRTOS\r
- * threads continuously, so the timing information in the FreeRTOS+Trace logs\r
- * have no meaningful units. See the documentation page for the Windows\r
- * simulator for further explanation:\r
+ * NOTE: Windows will not be running the FreeRTOS demo threads continuously, so\r
+ * do not expect to get real time behaviour from the FreeRTOS Windows port, or\r
+ * this demo application. Also, the timing information in the FreeRTOS+Trace\r
+ * logs have no meaningful units. See the documentation page for the Windows\r
+ * port for further information:\r
* http://www.freertos.org/FreeRTOS-Windows-Simulator-Emulator-for-Visual-Studio-and-Eclipse-MingW.html\r
- * - READ THE WEB DOCUMENTATION FOR THIS PORT FOR MORE INFORMATION ON USING IT -\r
*\r
* NOTE 2: This project provides two demo applications. A simple blinky style\r
* project, and a more comprehensive test and demo application. The\r
* mainCREATE_SIMPLE_BLINKY_DEMO_ONLY setting in main.c is used to select\r
* between the two. See the notes on using mainCREATE_SIMPLE_BLINKY_DEMO_ONLY\r
- * in main.c. This file implements the simply blinky style version.\r
+ * in main.c. This file implements the simply blinky version. Console output\r
+ * is used in place of the normal LED toggling.\r
*\r
* NOTE 3: This file only contains the source code that is specific to the\r
* basic demo. Generic functions, such FreeRTOS hook functions, are defined\r
*\r
* The Queue Send Task:\r
* The queue send task is implemented by the prvQueueSendTask() function in\r
- * this file. It uses vTaskDelayUntil() to create a period task that sends the\r
- * value 100 to the queue every 200 milliseconds (please read the notes above\r
- * regarding the accuracy of timing under Windows).\r
+ * this file. It uses vTaskDelayUntil() to create a periodic task that sends\r
+ * the value 100 to the queue every 200 milliseconds (please read the notes\r
+ * above regarding the accuracy of timing under Windows).\r
*\r
* The Queue Send Software Timer:\r
* The timer is a one-shot timer that is reset by a key press. The timer's\r
* in this file. prvQueueReceiveTask() waits for data to arrive on the queue.\r
* When data is received, the task checks the value of the data, then outputs a\r
* message to indicate if the data came from the queue send task or the queue\r
- * send software timer. As the queue send task writes to the queue every 200ms,\r
- * the queue receive task will print a message indicating that it received data\r
- * from the queue send task every 200ms. The queue receive task will print a\r
- * message indicating that it received data from the queue send software timer\r
- * 2 seconds after a key was last pressed.\r
+ * send software timer.\r
+ *\r
+ * Expected Behaviour:\r
+ * - The queue send task writes to the queue every 200ms, so every 200ms the\r
+ * queue receive task will output a message indicating that data was received\r
+ * on the queue from the queue send task.\r
+ * - The queue send software timer has a period of two seconds, and is reset\r
+ * each time a key is pressed. So if two seconds expire without a key being\r
+ * pressed then the queue receive task will output a message indicating that\r
+ * data was received on the queue from the queue send software timer.\r
+ *\r
+ * NOTE: Console input and output relies on Windows system calls, which can\r
+ * interfere with the execution of the FreeRTOS Windows port. This demo only\r
+ * uses Windows system call occasionally. Heavier use of Windows system calls\r
+ * can crash the port.\r
*/\r
\r
/* Standard includes. */\r
#define mainQUEUE_SEND_TASK_PRIORITY ( tskIDLE_PRIORITY + 1 )\r
\r
/* The rate at which data is sent to the queue. The times are converted from\r
-milliseconds to ticks by the pdMS_TO_TICKS() macro where they are used. */\r
-#define mainTASK_SEND_FREQUENCY_MS 200\r
-#define mainTIMER_SEND_FREQUENCY_MS 2000\r
+milliseconds to ticks using the pdMS_TO_TICKS() macro. */\r
+#define mainTASK_SEND_FREQUENCY_MS pdMS_TO_TICKS( 200UL )\r
+#define mainTIMER_SEND_FREQUENCY_MS pdMS_TO_TICKS( 2000UL )\r
\r
-/* The number of items the queue can hold. */\r
+/* The number of items the queue can hold at once. */\r
#define mainQUEUE_LENGTH ( 2 )\r
\r
-/* Values passed to the two tasks just to check the task parameter\r
-functionality. */\r
-#define mainQUEUE_SEND_PARAMETER ( 0x1111UL )\r
-#define mainQUEUE_RECEIVE_PARAMETER ( 0x22UL )\r
-\r
/* The values sent to the queue receive task from the queue send task and the\r
queue send software timer respectively. */\r
#define mainVALUE_SENT_FROM_TASK ( 100UL )\r
\r
/*-----------------------------------------------------------*/\r
\r
+/*** SEE THE COMMENTS AT THE TOP OF THIS FILE ***/\r
void main_blinky( void )\r
{\r
-const TickType_t xTimerPeriod = pdMS_TO_TICKS( mainTIMER_SEND_FREQUENCY_MS );\r
+const TickType_t xTimerPeriod = mainTIMER_SEND_FREQUENCY_MS;\r
\r
/* Create the queue. */\r
- xQueue = xQueueCreate( mainQUEUE_LENGTH, sizeof( unsigned long ) );\r
+ xQueue = xQueueCreate( mainQUEUE_LENGTH, sizeof( uint32_t ) );\r
\r
if( xQueue != NULL )\r
{\r
/* Start the two tasks as described in the comments at the top of this\r
file. */\r
- xTaskCreate( prvQueueReceiveTask, /* The function that implements the task. */\r
- "Rx", /* The text name assigned to the task - for debug only as it is not used by the kernel. */\r
- configMINIMAL_STACK_SIZE, /* The size of the stack to allocate to the task. */\r
- ( void * ) mainQUEUE_RECEIVE_PARAMETER, /* The parameter passed to the task - just to check the functionality. */\r
- mainQUEUE_RECEIVE_TASK_PRIORITY, /* The priority assigned to the task. */\r
- NULL ); /* The task handle is not required, so NULL is passed. */\r
+ xTaskCreate( prvQueueReceiveTask, /* The function that implements the task. */\r
+ "Rx", /* The text name assigned to the task - for debug only as it is not used by the kernel. */\r
+ configMINIMAL_STACK_SIZE, /* The size of the stack to allocate to the task. */\r
+ NULL, /* The parameter passed to the task - not used in this simple case. */\r
+ mainQUEUE_RECEIVE_TASK_PRIORITY,/* The priority assigned to the task. */\r
+ NULL ); /* The task handle is not required, so NULL is passed. */\r
\r
- xTaskCreate( prvQueueSendTask, "TX", configMINIMAL_STACK_SIZE, ( void * ) mainQUEUE_SEND_PARAMETER, mainQUEUE_SEND_TASK_PRIORITY, NULL );\r
+ xTaskCreate( prvQueueSendTask, "TX", configMINIMAL_STACK_SIZE, NULL, mainQUEUE_SEND_TASK_PRIORITY, NULL );\r
\r
/* Create the software timer, but don't start it yet. */\r
xTimer = xTimerCreate( "Timer", /* The text name assigned to the software timer - for debug only as it is not used by the kernel. */\r
static void prvQueueSendTask( void *pvParameters )\r
{\r
TickType_t xNextWakeTime;\r
-const TickType_t xBlockTime = pdMS_TO_TICKS( mainTASK_SEND_FREQUENCY_MS );\r
+const TickType_t xBlockTime = mainTASK_SEND_FREQUENCY_MS;\r
const uint32_t ulValueToSend = mainVALUE_SENT_FROM_TASK;\r
\r
- /* Remove compiler warning in the case that configASSERT() is not\r
- defined. */\r
+ /* Prevent the compiler warning about the unused parameter. */\r
( void ) pvParameters;\r
\r
- /* Check the task parameter is as expected. */\r
- configASSERT( ( ( unsigned long ) pvParameters ) == mainQUEUE_SEND_PARAMETER );\r
-\r
/* Initialise xNextWakeTime - this only needs to be done once. */\r
xNextWakeTime = xTaskGetTickCount();\r
\r
for( ;; )\r
{\r
/* Place this task in the blocked state until it is time to run again.\r
- The block time is specified in ticks, the constant used converts ticks\r
- to ms. While in the Blocked state this task will not consume any CPU\r
- time. */\r
+ The block time is specified in ticks, pdMS_TO_TICKS() was used to\r
+ convert a time specified in milliseconds into a time specified in ticks.\r
+ While in the Blocked state this task will not consume any CPU time. */\r
vTaskDelayUntil( &xNextWakeTime, xBlockTime );\r
\r
/* Send to the queue - causing the queue receive task to unblock and\r
- toggle the LED. 0 is used as the block time so the sending operation\r
+ write to the console. 0 is used as the block time so the send operation\r
will not block - it shouldn't need to block as the queue should always\r
have at least one space at this point in the code. */\r
xQueueSend( xQueue, &ulValueToSend, 0U );\r
{\r
const uint32_t ulValueToSend = mainVALUE_SENT_FROM_TIMER;\r
\r
+ /* This is the software timer callback function. The software timer has a\r
+ period of two seconds and is reset each time a key is pressed. This\r
+ callback function will execute if the timer expires, which will only happen\r
+ if a key is not pressed for two seconds. */\r
+\r
/* Avoid compiler warnings resulting from the unused parameter. */\r
( void ) xTimerHandle;\r
\r
\r
static void prvQueueReceiveTask( void *pvParameters )\r
{\r
-unsigned long ulReceivedValue;\r
+uint32_t ulReceivedValue;\r
\r
- /* Remove compiler warning in the case that configASSERT() is not\r
- defined. */\r
+ /* Prevent the compiler warning about the unused parameter. */\r
( void ) pvParameters;\r
\r
- /* Check the task parameter is as expected. */\r
- configASSERT( ( ( unsigned long ) pvParameters ) == mainQUEUE_RECEIVE_PARAMETER );\r
-\r
for( ;; )\r
{\r
/* Wait until something arrives in the queue - this task will block\r
indefinitely provided INCLUDE_vTaskSuspend is set to 1 in\r
- FreeRTOSConfig.h. */\r
+ FreeRTOSConfig.h. It will not use any CPU time while it is in the\r
+ Blocked state. */\r
xQueueReceive( xQueue, &ulReceivedValue, portMAX_DELAY );\r
\r
/* To get here something must have been received from the queue, but\r
- is it the expected value? Normally calling printf() from a task is not\r
+ is it an expected value? Normally calling printf() from a task is not\r
a good idea. Here there is lots of stack space and only one task is\r
- using console IO so it is ok. */\r
+ using console IO so it is ok. However, note the comments at the top of\r
+ this file about the risks of making Windows system calls (such as \r
+ console output) from a FreeRTOS task. */\r
if( ulReceivedValue == mainVALUE_SENT_FROM_TASK )\r
{\r
printf( "Message received from task\r\n" );\r
projects / freertos / blobdiff