2 * FreeRTOS Kernel V10.0.0
\r
3 * Copyright (C) 2017 Amazon.com, Inc. or its affiliates. All Rights Reserved.
\r
5 * Permission is hereby granted, free of charge, to any person obtaining a copy of
\r
6 * this software and associated documentation files (the "Software"), to deal in
\r
7 * the Software without restriction, including without limitation the rights to
\r
8 * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
\r
9 * the Software, and to permit persons to whom the Software is furnished to do so,
\r
10 * subject to the following conditions:
\r
12 * The above copyright notice and this permission notice shall be included in all
\r
13 * copies or substantial portions of the Software. If you wish to use our Amazon
\r
14 * FreeRTOS name, please do so in a fair use way that does not cause confusion.
\r
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
\r
17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
\r
18 * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
\r
19 * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
\r
20 * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
\r
21 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
\r
23 * http://www.FreeRTOS.org
\r
24 * http://aws.amazon.com/freertos
\r
26 * 1 tab == 4 spaces!
\r
30 * This demo application file demonstrates the use of queues to pass data
\r
31 * between co-routines.
\r
33 * N represents the number of 'fixed delay' co-routines that are created and
\r
34 * is set during initialisation.
\r
36 * N 'fixed delay' co-routines are created that just block for a fixed
\r
37 * period then post the number of an LED onto a queue. Each such co-routine
\r
38 * uses a different block period. A single 'flash' co-routine is also created
\r
39 * that blocks on the same queue, waiting for the number of the next LED it
\r
40 * should flash. Upon receiving a number it simply toggle the instructed LED
\r
41 * then blocks on the queue once more. In this manner each LED from LED 0 to
\r
42 * LED N-1 is caused to flash at a different rate.
\r
44 * The 'fixed delay' co-routines are created with co-routine priority 0. The
\r
45 * flash co-routine is created with co-routine priority 1. This means that
\r
46 * the queue should never contain more than a single item. This is because
\r
47 * posting to the queue will unblock the 'flash' co-routine, and as this has
\r
48 * a priority greater than the tasks posting to the queue it is guaranteed to
\r
49 * have emptied the queue and blocked once again before the queue can contain
\r
50 * any more date. An error is indicated if an attempt to post data to the
\r
51 * queue fails - indicating that the queue is already full.
\r
55 /* Scheduler includes. */
\r
56 #include "FreeRTOS.h"
\r
57 #include "croutine.h"
\r
60 /* Demo application includes. */
\r
61 #include "partest.h"
\r
62 #include "crflash.h"
\r
64 /* The queue should only need to be of length 1. See the description at the
\r
66 #define crfQUEUE_LENGTH 1
\r
68 #define crfFIXED_DELAY_PRIORITY 0
\r
69 #define crfFLASH_PRIORITY 1
\r
71 /* Only one flash co-routine is created so the index is not significant. */
\r
72 #define crfFLASH_INDEX 0
\r
74 /* Don't allow more than crfMAX_FLASH_TASKS 'fixed delay' co-routines to be
\r
76 #define crfMAX_FLASH_TASKS 8
\r
78 /* We don't want to block when posting to the queue. */
\r
79 #define crfPOSTING_BLOCK_TIME 0
\r
82 * The 'fixed delay' co-routine as described at the top of the file.
\r
84 static void prvFixedDelayCoRoutine( CoRoutineHandle_t xHandle, UBaseType_t uxIndex );
\r
87 * The 'flash' co-routine as described at the top of the file.
\r
89 static void prvFlashCoRoutine( CoRoutineHandle_t xHandle, UBaseType_t uxIndex );
\r
91 /* The queue used to pass data between the 'fixed delay' co-routines and the
\r
92 'flash' co-routine. */
\r
93 static QueueHandle_t xFlashQueue;
\r
95 /* This will be set to pdFALSE if we detect an error. */
\r
96 static BaseType_t xCoRoutineFlashStatus = pdPASS;
\r
98 /*-----------------------------------------------------------*/
\r
101 * See the header file for details.
\r
103 void vStartFlashCoRoutines( UBaseType_t uxNumberToCreate )
\r
105 UBaseType_t uxIndex;
\r
107 if( uxNumberToCreate > crfMAX_FLASH_TASKS )
\r
109 uxNumberToCreate = crfMAX_FLASH_TASKS;
\r
112 /* Create the queue used to pass data between the co-routines. */
\r
113 xFlashQueue = xQueueCreate( crfQUEUE_LENGTH, sizeof( UBaseType_t ) );
\r
117 /* Create uxNumberToCreate 'fixed delay' co-routines. */
\r
118 for( uxIndex = 0; uxIndex < uxNumberToCreate; uxIndex++ )
\r
120 xCoRoutineCreate( prvFixedDelayCoRoutine, crfFIXED_DELAY_PRIORITY, uxIndex );
\r
123 /* Create the 'flash' co-routine. */
\r
124 xCoRoutineCreate( prvFlashCoRoutine, crfFLASH_PRIORITY, crfFLASH_INDEX );
\r
127 /*-----------------------------------------------------------*/
\r
129 static void prvFixedDelayCoRoutine( CoRoutineHandle_t xHandle, UBaseType_t uxIndex )
\r
131 /* Even though this is a co-routine the xResult variable does not need to be
\r
132 static as we do not need it to maintain its state between blocks. */
\r
133 BaseType_t xResult;
\r
134 /* The uxIndex parameter of the co-routine function is used as an index into
\r
135 the xFlashRates array to obtain the delay period to use. */
\r
136 static const TickType_t xFlashRates[ crfMAX_FLASH_TASKS ] = { 150 / portTICK_PERIOD_MS,
\r
137 200 / portTICK_PERIOD_MS,
\r
138 250 / portTICK_PERIOD_MS,
\r
139 300 / portTICK_PERIOD_MS,
\r
140 350 / portTICK_PERIOD_MS,
\r
141 400 / portTICK_PERIOD_MS,
\r
142 450 / portTICK_PERIOD_MS,
\r
143 500 / portTICK_PERIOD_MS };
\r
145 /* Co-routines MUST start with a call to crSTART. */
\r
146 crSTART( xHandle );
\r
150 /* Post our uxIndex value onto the queue. This is used as the LED to
\r
152 crQUEUE_SEND( xHandle, xFlashQueue, ( void * ) &uxIndex, crfPOSTING_BLOCK_TIME, &xResult );
\r
154 if( xResult != pdPASS )
\r
156 /* For the reasons stated at the top of the file we should always
\r
157 find that we can post to the queue. If we could not then an error
\r
159 xCoRoutineFlashStatus = pdFAIL;
\r
162 crDELAY( xHandle, xFlashRates[ uxIndex ] );
\r
165 /* Co-routines MUST end with a call to crEND. */
\r
168 /*-----------------------------------------------------------*/
\r
170 static void prvFlashCoRoutine( CoRoutineHandle_t xHandle, UBaseType_t uxIndex )
\r
172 /* Even though this is a co-routine the variable do not need to be
\r
173 static as we do not need it to maintain their state between blocks. */
\r
174 BaseType_t xResult;
\r
175 UBaseType_t uxLEDToFlash;
\r
177 /* Co-routines MUST start with a call to crSTART. */
\r
178 crSTART( xHandle );
\r
183 /* Block to wait for the number of the LED to flash. */
\r
184 crQUEUE_RECEIVE( xHandle, xFlashQueue, &uxLEDToFlash, portMAX_DELAY, &xResult );
\r
186 if( xResult != pdPASS )
\r
188 /* We would not expect to wake unless we received something. */
\r
189 xCoRoutineFlashStatus = pdFAIL;
\r
193 /* We received the number of an LED to flash - flash it! */
\r
194 vParTestToggleLED( uxLEDToFlash );
\r
198 /* Co-routines MUST end with a call to crEND. */
\r
201 /*-----------------------------------------------------------*/
\r
203 BaseType_t xAreFlashCoRoutinesStillRunning( void )
\r
205 /* Return pdPASS or pdFAIL depending on whether an error has been detected
\r
207 return xCoRoutineFlashStatus;
\r