begriffs open source - cmsis-freertos/blob

1 /*

2 * FreeRTOS Kernel V10.2.1

4 *

5 * Permission is hereby granted, free of charge, to any person obtaining a copy of

6 * this software and associated documentation files (the "Software"), to deal in

7 * the Software without restriction, including without limitation the rights to

8 * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of

9 * the Software, and to permit persons to whom the Software is furnished to do so,

10 * subject to the following conditions:

11 *

12 * The above copyright notice and this permission notice shall be included in all

13 * copies or substantial portions of the Software.

14 *

15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS

17 * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR

18 * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER

19 * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN

20 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

21 *

22 * http://www.FreeRTOS.org

23 * http://aws.amazon.com/freertos

24 *

25 * 1 tab == 4 spaces!

26 */

27

28 /*

29 * Creates all the demo application tasks, then starts the scheduler. The WEB

30 * documentation provides more details of the demo application tasks.

31 *

32 * This demo is configured to execute on the ES449 prototyping board from

33 * SoftBaugh. The ES449 has a built in LCD display and a single built in user

34 * LED. Therefore, in place of flashing an LED, the 'flash' and 'check' tasks

35 * toggle '*' characters on the LCD. The left most '*' represents LED 0, the

36 * next LED 1, etc.

37 *

38 * Main. c also creates a task called 'Check'. This only executes every three

39 * seconds but has the highest priority so is guaranteed to get processor time.

40 * Its main function is to check that all the other tasks are still operational.

41 * Each task that does not flash an LED maintains a unique count that is

42 * incremented each time the task successfully completes its function. Should

43 * any error occur within such a task the count is permanently halted. The

44 * 'check' task inspects the count of each task to ensure it has changed since

45 * the last time the check task executed. If all the count variables have

46 * changed all the tasks are still executing error free, and the check task

47 * toggles an LED with a three second period. Should any task contain an error

48 * at any time the LED toggle rate will increase to 500ms.

49 *

50 * Please read the documentation for the MSP430 port available on

51 * http://www.FreeRTOS.org.

52 */

53

54 /* Standard includes. */

55 #include <stdlib.h>

56 #include <signal.h>

57

58 /* Scheduler includes. */

59 #include "FreeRTOS.h"

60 #include "task.h"

61

62 /* Demo application includes. */

63 #include "partest.h"

64 #include "flash.h"

65 #include "integer.h"

66 #include "comtest2.h"

67 #include "PollQ.h"

68

69 /* Constants required for hardware setup. */

70 #define mainALL_BITS_OUTPUT ( ( unsigned char ) 0xff )

71 #define mainMAX_FREQUENCY ( ( unsigned char ) 121 )

72

73 /* Constants that define the LED's used by the various tasks. [in this case

74 the '*' characters on the LCD represent LED's] */

75 #define mainCHECK_LED ( 4 )

76 #define mainCOM_TEST_LED ( 10 )

77

78 /* Demo task priorities. */

79 #define mainCHECK_TASK_PRIORITY ( tskIDLE_PRIORITY + 3 )

80 #define mainCOM_TEST_PRIORITY ( tskIDLE_PRIORITY + 2 )

81 #define mainQUEUE_POLL_PRIORITY ( tskIDLE_PRIORITY + 2 )

82 #define mainLED_TASK_PRIORITY ( tskIDLE_PRIORITY + 1 )

83

84 /* Baud rate used by the COM test tasks. */

85 #define mainCOM_TEST_BAUD_RATE ( ( unsigned long ) 19200 )

86

87 /* The frequency at which the 'Check' tasks executes. See the comments at the

88 top of the page. When the system is operating error free the 'Check' task

89 toggles an LED every three seconds. If an error is discovered in any task the

90 rate is increased to 500 milliseconds. [in this case the '*' characters on the

91 LCD represent LED's]*/

92 #define mainNO_ERROR_CHECK_DELAY ( ( TickType_t ) 3000 / portTICK_PERIOD_MS )

93 #define mainERROR_CHECK_DELAY ( ( TickType_t ) 500 / portTICK_PERIOD_MS )

94

95 /*

96 * The function that implements the Check task. See the comments at the head

97 * of the page for implementation details.

98 */

99 static void vErrorChecks( void *pvParameters );

100

101 /*

102 * Called by the Check task. Returns pdPASS if all the other tasks are found

103 * to be operating without error - otherwise returns pdFAIL.

104 */

105 static short prvCheckOtherTasksAreStillRunning( void );

106

107 /*

108 * Perform the hardware setup required by the ES449 in order to run the demo

109 * application.

110 */

111 static void prvSetupHardware( void );

112

113 /* Used to detect the idle hook function stalling. */

114 static volatile unsigned long ulIdleLoops = 0UL;

115

116 /*-----------------------------------------------------------*/

117

118 /*

119 * Start the demo application tasks - then start the real time scheduler.

120 */

121 int main( void )

122 {

123 /* Setup the hardware ready for the demo. */

124 prvSetupHardware();

125 vParTestInitialise();

126

127 /* Start the standard demo application tasks. */

128 vStartLEDFlashTasks( mainLED_TASK_PRIORITY );

129 vStartIntegerMathTasks( tskIDLE_PRIORITY );

130 vAltStartComTestTasks( mainCOM_TEST_PRIORITY, mainCOM_TEST_BAUD_RATE, mainCOM_TEST_LED - 1 );

131 vStartPolledQueueTasks( mainQUEUE_POLL_PRIORITY );

132

133 /* Start the 'Check' task which is defined in this file. */

134 xTaskCreate( vErrorChecks, "Check", configMINIMAL_STACK_SIZE, NULL, mainCHECK_TASK_PRIORITY, NULL );

135

136 /* Start the scheduler. */

137 vTaskStartScheduler();

138

139 /* As the scheduler has been started the demo applications tasks will be

140 executing and we should never get here! */

141 return 0;

142 }

143 /*-----------------------------------------------------------*/

144

145 static void vErrorChecks( void *pvParameters )

146 {

147 static volatile unsigned long ulDummyVariable = 3UL;

148 TickType_t xDelayPeriod = mainNO_ERROR_CHECK_DELAY;

149

150 /* Cycle for ever, delaying then checking all the other tasks are still

151 operating without error. */

152 for( ;; )

153 {

154 /* Wait until it is time to check again. The time we wait here depends

155 on whether an error has been detected or not. When an error is

156 detected the time is shortened resulting in a faster LED flash rate. */

157 vTaskDelay( xDelayPeriod );

158

159 /* Perform a bit of 32bit maths to ensure the registers used by the

160 integer tasks get some exercise outside of the integer tasks

161 themselves. The result here is not important we are just deliberately

162 changing registers used by other tasks to ensure that their context

163 switch is operating as required. - see the demo application

164 documentation for more info. */

165 ulDummyVariable *= 3UL;

166

167 /* See if the other tasks are all ok. */

168 if( prvCheckOtherTasksAreStillRunning() != pdPASS )

169 {

170 /* An error occurred in one of the tasks so shorten the delay

171 period - which has the effect of increasing the frequency of the

172 LED toggle. */

173 xDelayPeriod = mainERROR_CHECK_DELAY;

174 }

175

176 /* Flash! */

177 vParTestToggleLED( mainCHECK_LED );

178 }

179 }

180 /*-----------------------------------------------------------*/

181

182 static short prvCheckOtherTasksAreStillRunning( void )

183 {

184 static short sNoErrorFound = pdTRUE;

185 static unsigned long ulLastIdleLoops = 0UL;

186

187 /* The demo tasks maintain a count that increments every cycle of the task

188 provided that the task has never encountered an error. This function

189 checks the counts maintained by the tasks to ensure they are still being

190 incremented. A count remaining at the same value between calls therefore

191 indicates that an error has been detected. Only tasks that do not flash

192 an LED are checked. */

193

194 if( xAreIntegerMathsTaskStillRunning() != pdTRUE )

195 {

196 sNoErrorFound = pdFALSE;

197 }

198

199 if( xAreComTestTasksStillRunning() != pdTRUE )

200 {

201 sNoErrorFound = pdFALSE;

202 }

203

204 if( xArePollingQueuesStillRunning() != pdTRUE )

205 {

206 sNoErrorFound = pdFALSE;

207 }

208

209 if( ulLastIdleLoops == ulIdleLoops )

210 {

211 sNoErrorFound = pdFALSE;

212 }

213

214 ulLastIdleLoops = ulIdleLoops;

215

216 return sNoErrorFound;

217 }

218 /*-----------------------------------------------------------*/

219

220 static void prvSetupHardware( void )

221 {

222 /* Stop the watchdog. */

223 WDTCTL = WDTPW + WDTHOLD;

224

225 /* Setup DCO+ for ( xtal * D * (N + 1) ) operation. */

226 FLL_CTL0 |= DCOPLUS + XCAP18PF;

227

228 /* X2 DCO frequency, 8MHz nominal DCO */

229 SCFI0 |= FN_4;

230

231 /* (121+1) x 32768 x 2 = 7.99 Mhz */

232 SCFQCTL = mainMAX_FREQUENCY;

233

234 /* Setup the IO as per the SoftBaugh demo for the same target hardware. */

235 P1SEL = 0x32;

236 P2SEL = 0x00;

237 P3SEL = 0x00;

238 P4SEL = 0xFC;

239 P5SEL = 0xFF;

240 }

241 /*-----------------------------------------------------------*/

242

243 void vApplicationIdleHook( void );

244 void vApplicationIdleHook( void )

245 {

246 /* Simple put the CPU into lowpower mode. */

247 _BIS_SR( LPM3_bits );

248 ulIdleLoops++;

249 }

250 /*-----------------------------------------------------------*/