2 FreeRTOS V7.6.0 - Copyright (C) 2013 Real Time Engineers Ltd.
\r
5 VISIT http://www.FreeRTOS.org TO ENSURE YOU ARE USING THE LATEST VERSION.
\r
7 ***************************************************************************
\r
9 * FreeRTOS provides completely free yet professionally developed, *
\r
10 * robust, strictly quality controlled, supported, and cross *
\r
11 * platform software that has become a de facto standard. *
\r
13 * Help yourself get started quickly and support the FreeRTOS *
\r
14 * project by purchasing a FreeRTOS tutorial book, reference *
\r
15 * manual, or both from: http://www.FreeRTOS.org/Documentation *
\r
19 ***************************************************************************
\r
21 This file is part of the FreeRTOS distribution.
\r
23 FreeRTOS is free software; you can redistribute it and/or modify it under
\r
24 the terms of the GNU General Public License (version 2) as published by the
\r
25 Free Software Foundation >>!AND MODIFIED BY!<< the FreeRTOS exception.
\r
27 >>! NOTE: The modification to the GPL is included to allow you to distribute
\r
28 >>! a combined work that includes FreeRTOS without being obliged to provide
\r
29 >>! the source code for proprietary components outside of the FreeRTOS
\r
32 FreeRTOS is distributed in the hope that it will be useful, but WITHOUT ANY
\r
33 WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
\r
34 FOR A PARTICULAR PURPOSE. Full license text is available from the following
\r
35 link: http://www.freertos.org/a00114.html
\r
39 ***************************************************************************
\r
41 * Having a problem? Start by reading the FAQ "My application does *
\r
42 * not run, what could be wrong?" *
\r
44 * http://www.FreeRTOS.org/FAQHelp.html *
\r
46 ***************************************************************************
\r
48 http://www.FreeRTOS.org - Documentation, books, training, latest versions,
\r
49 license and Real Time Engineers Ltd. contact details.
\r
51 http://www.FreeRTOS.org/plus - A selection of FreeRTOS ecosystem products,
\r
52 including FreeRTOS+Trace - an indispensable productivity tool, a DOS
\r
53 compatible FAT file system, and our tiny thread aware UDP/IP stack.
\r
55 http://www.OpenRTOS.com - Real Time Engineers ltd license FreeRTOS to High
\r
56 Integrity Systems to sell under the OpenRTOS brand. Low cost OpenRTOS
\r
57 licenses offer ticketed support, indemnification and middleware.
\r
59 http://www.SafeRTOS.com - High Integrity Systems also provide a safety
\r
60 engineered and independently SIL3 certified version for use in safety and
\r
61 mission critical applications that require provable dependability.
\r
67 * This demo application creates seven co-routines and one task (two including
\r
68 * the idle task). The co-routines execute as part of the idle task hook.
\r
70 * Five of the created co-routines are the standard 'co-routine flash'
\r
71 * co-routines contained within the Demo/Common/Minimal/crflash.c file and
\r
72 * documented on the FreeRTOS.org WEB site.
\r
74 * The 'LCD Task' rotates a string on the LCD, delaying between each character
\r
75 * as necessitated by the slow interface, and delaying between each string just
\r
76 * long enough to enable the text to be read.
\r
78 * The sixth co-routine controls the transmission of a string to UART 0. The
\r
79 * co-routine periodically sends the first character of the string to the UART,
\r
80 * with the UART's TxEnd interrupt being used to transmit the remaining
\r
81 * characters. The UART's RxEnd interrupt receives the characters and places
\r
82 * them on a queue to be processed by the seventh and final co-routine. An
\r
83 * error is latched should an unexpected character be received, or any
\r
84 * character be received out of sequence.
\r
86 * A loopback connector is required to ensure that each character transmitted
\r
87 * on the UART is also received on the same UART. For test purposes the UART
\r
88 * FIFO's are not utalised in order to maximise the interrupt overhead. Also
\r
89 * a pseudo random interval is used between the start of each transmission in
\r
90 * order that the resultant interrupts are more randomly distributed and
\r
91 * therefore more likely to highlight any problems.
\r
93 * The flash co-routines control LED's zero to four. LED five is toggled each
\r
94 * time the string is transmitted on the UART. LED six is toggled each time
\r
95 * the string is CORRECTLY received on the UART. LED seven is latched on should
\r
96 * an error be detected in any task or co-routine.
\r
98 * In addition the idle task makes repetative calls to
\r
99 * prvSetAndCheckRegisters(). This simply loads the general purpose registers
\r
100 * with a known value, then checks each register to ensure the held value is
\r
101 * still correct. As a low priority task this checking routine is likely to
\r
102 * get repeatedly swapped in and out. A register being found to contain an
\r
103 * incorrect value is therefore indicative of an error in the task switching
\r
108 /* Scheduler include files. */
\r
109 #include "FreeRTOS.h"
\r
112 #include "croutine.h"
\r
114 /* Demo application include files. */
\r
115 #include "partest.h"
\r
116 #include "crflash.h"
\r
118 /* Library include files. */
\r
119 #include "DriverLib.h"
\r
121 /* The time to delay between writing each character to the LCD. */
\r
122 #define mainCHAR_WRITE_DELAY ( 2 / portTICK_RATE_MS )
\r
124 /* The time to delay between writing each string to the LCD. */
\r
125 #define mainSTRING_WRITE_DELAY ( 400 / portTICK_RATE_MS )
\r
127 /* The number of flash co-routines to create. */
\r
128 #define mainNUM_FLASH_CO_ROUTINES ( 5 )
\r
130 /* The length of the queue used to pass received characters to the Comms Rx
\r
132 #define mainRX_QUEUE_LEN ( 5 )
\r
134 /* The priority of the co-routine used to initiate the transmission of the
\r
135 string on UART 0. */
\r
136 #define mainTX_CO_ROUTINE_PRIORITY ( 1 )
\r
138 /* The priority of the co-routine used to receive characters from the UART. */
\r
139 #define mainRX_CO_ROUTINE_PRIORITY ( 2 )
\r
141 /* Only one co-routine is created so its index is not important. */
\r
142 #define mainTX_CO_ROUTINE_INDEX ( 0 )
\r
143 #define mainRX_CO_ROUTINE_INDEX ( 0 )
\r
145 /* The time between transmissions of the string on UART 0. This is pseudo
\r
146 random in order to generate a bit or randomness to when the interrupts occur.*/
\r
147 #define mainMIN_TX_DELAY ( 40 / portTICK_RATE_MS )
\r
148 #define mainMAX_TX_DELAY ( ( portTickType ) 0x7f )
\r
149 #define mainOFFSET_TIME ( ( portTickType ) 3 )
\r
151 /* The time the Comms Rx task should wait to receive a character. This should
\r
152 be slightly longer than the time between transmissions. If we do not receive
\r
153 a character after this time then there must be an error in the transmission or
\r
154 the timing of the transmission. */
\r
155 #define mainCOMMS_RX_DELAY ( mainMAX_TX_DELAY + 20 )
\r
157 /* The task priorites. */
\r
158 #define mainLCD_TASK_PRIORITY ( tskIDLE_PRIORITY )
\r
159 #define mainCOMMS_RX_TASK_PRIORITY ( tskIDLE_PRIORITY + 1 )
\r
161 /* The LED's toggled by the various tasks. */
\r
162 #define mainCOMMS_FAIL_LED ( 7 )
\r
163 #define mainCOMMS_RX_LED ( 6 )
\r
164 #define mainCOMMS_TX_LED ( 5 )
\r
166 /* The baud rate used by the UART comms tasks/co-routine. */
\r
167 #define mainBAUD_RATE ( 57600 )
\r
169 /* FIFO setting for the UART. The FIFO is not used to create a better test. */
\r
170 #define mainFIFO_SET ( 0x10 )
\r
172 /* The string that is transmitted on the UART contains sequentially the
\r
173 characters from mainFIRST_TX_CHAR to mainLAST_TX_CHAR. */
\r
174 #define mainFIRST_TX_CHAR '0'
\r
175 #define mainLAST_TX_CHAR 'z'
\r
177 /* Just used to walk through the program memory in order that some random data
\r
178 can be generated. */
\r
179 #define mainTOTAL_PROGRAM_MEMORY ( ( unsigned long * ) ( 8 * 1024 ) )
\r
180 #define mainFIRST_PROGRAM_BYTES ( ( unsigned long * ) 4 )
\r
182 /* The error routine that is called if the driver library encounters an error. */
\r
185 __error__(char *pcFilename, unsigned long ulLine)
\r
190 /*-----------------------------------------------------------*/
\r
193 * The task that rotates text on the LCD.
\r
195 static void vLCDTask( void * pvParameters );
\r
198 * The task that receives the characters from UART 0.
\r
200 static void vCommsRxCoRoutine( CoRoutineHandle_t xHandle, unsigned portBASE_TYPE uxIndex );
\r
203 * The co-routine that periodically initiates the transmission of the string on
\r
206 static void vSerialTxCoRoutine( CoRoutineHandle_t xHandle, unsigned portBASE_TYPE uxIndex );
\r
209 * Writes a string the the LCD.
\r
211 static void prvWriteString( const char *pcString );
\r
214 * Initialisation routine for the UART.
\r
216 static void vSerialInit( void );
\r
219 * Thread safe write to the PDC.
\r
221 static void prvPDCWrite( char cAddress, char cData );
\r
224 * Function to simply set a known value into the general purpose registers
\r
225 * then read them back to ensure they remain set correctly. An incorrect value
\r
226 * being indicative of an error in the task switching mechanism.
\r
228 void prvSetAndCheckRegisters( void );
\r
231 * Latch the LED that indicates that an error has occurred.
\r
233 void vSetErrorLED( void );
\r
236 * Sets up the PLL and ports used by the demo.
\r
238 static void prvSetupHardware( void );
\r
240 /*-----------------------------------------------------------*/
\r
242 /* Error flag set to pdFAIL if an error is encountered in the tasks/co-routines
\r
243 defined within this file. */
\r
244 unsigned portBASE_TYPE uxErrorStatus = pdPASS;
\r
246 /* The next character to transmit. */
\r
247 static char cNextChar;
\r
249 /* The queue used to transmit characters from the interrupt to the Comms Rx
\r
251 static xQueueHandle xCommsQueue;
\r
253 /*-----------------------------------------------------------*/
\r
257 /* Create the queue used to communicate between the UART ISR and the Comms
\r
259 xCommsQueue = xQueueCreate( mainRX_QUEUE_LEN, sizeof( char ) );
\r
261 /* Setup the ports used by the demo and the clock. */
\r
262 prvSetupHardware();
\r
264 /* Create the co-routines that flash the LED's. */
\r
265 vStartFlashCoRoutines( mainNUM_FLASH_CO_ROUTINES );
\r
267 /* Create the co-routine that initiates the transmission of characters
\r
269 xCoRoutineCreate( vSerialTxCoRoutine, mainTX_CO_ROUTINE_PRIORITY, mainTX_CO_ROUTINE_INDEX );
\r
271 /* Create the co-routine that receives characters from the UART. */
\r
272 xCoRoutineCreate( vCommsRxCoRoutine, mainRX_CO_ROUTINE_PRIORITY, mainRX_CO_ROUTINE_INDEX );
\r
274 /* Create the LCD task. */
\r
275 xTaskCreate( vLCDTask, "LCD", configMINIMAL_STACK_SIZE, NULL, mainLCD_TASK_PRIORITY, NULL );
\r
277 /* Start the scheduler running the tasks and co-routines just created. */
\r
278 vTaskStartScheduler();
\r
280 /* Should not get here unless we did not have enough memory to start the
\r
285 /*-----------------------------------------------------------*/
\r
287 static void prvSetupHardware( void )
\r
289 /* Setup the PLL. */
\r
290 SysCtlClockSet( SYSCTL_SYSDIV_10 | SYSCTL_USE_PLL | SYSCTL_OSC_MAIN | SYSCTL_XTAL_6MHZ );
\r
292 /* Initialise the hardware used to talk to the LCD, LED's and UART. */
\r
294 vParTestInitialise();
\r
297 /*-----------------------------------------------------------*/
\r
299 void vApplicationIdleHook( void )
\r
301 /* The co-routines are executed in the idle task using the idle task
\r
305 /* Schedule the co-routines. */
\r
306 vCoRoutineSchedule();
\r
308 /* Run the register check function between each co-routine. */
\r
309 prvSetAndCheckRegisters();
\r
312 /*-----------------------------------------------------------*/
\r
314 static void prvWriteString( const char *pcString )
\r
316 /* Write pcString to the LED, pausing between each character. */
\r
317 prvPDCWrite(PDC_LCD_CSR, LCD_CLEAR);
\r
320 vTaskDelay( mainCHAR_WRITE_DELAY );
\r
321 prvPDCWrite( PDC_LCD_RAM, *pcString );
\r
325 /*-----------------------------------------------------------*/
\r
327 void vLCDTask( void * pvParameters )
\r
329 unsigned portBASE_TYPE uxIndex;
\r
330 const unsigned char ucCFGData[] = {
\r
331 0x30, /* Set data bus to 8-bits. */
\r
334 0x3C, /* Number of lines/font. */
\r
335 0x08, /* Display off. */
\r
336 0x01, /* Display clear. */
\r
337 0x06, /* Entry mode [cursor dir][shift]. */
\r
338 0x0C /* Display on [display on][curson on][blinking on]. */
\r
341 /* The strings that are written to the LCD. */
\r
342 const char *pcStringsToDisplay[] = {
\r
346 "www.FreeRTOS.org",
\r
350 /* Configure the LCD. */
\r
352 while( uxIndex < sizeof( ucCFGData ) )
\r
354 prvPDCWrite( PDC_LCD_CSR, ucCFGData[ uxIndex ] );
\r
356 vTaskDelay( mainCHAR_WRITE_DELAY );
\r
359 /* Turn the LCD Backlight on. */
\r
360 prvPDCWrite( PDC_CSR, 0x01 );
\r
362 /* Clear display. */
\r
363 vTaskDelay( mainCHAR_WRITE_DELAY );
\r
364 prvPDCWrite( PDC_LCD_CSR, LCD_CLEAR );
\r
369 /* Display the string on the LCD. */
\r
370 prvWriteString( pcStringsToDisplay[ uxIndex ] );
\r
372 /* Move on to the next string - wrapping if necessary. */
\r
374 if( *( pcStringsToDisplay[ uxIndex ] ) == 0x00 )
\r
377 /* Longer pause on the last string to be sent. */
\r
378 vTaskDelay( mainSTRING_WRITE_DELAY * 2 );
\r
381 /* Wait until it is time to move onto the next string. */
\r
382 vTaskDelay( mainSTRING_WRITE_DELAY );
\r
385 /*-----------------------------------------------------------*/
\r
387 static void vCommsRxCoRoutine( CoRoutineHandle_t xHandle, unsigned portBASE_TYPE uxIndex )
\r
389 static char cRxedChar, cExpectedChar = mainFIRST_TX_CHAR;
\r
390 portBASE_TYPE xResult;
\r
392 crSTART( xHandle );
\r
396 /* Wait for a character to be received. */
\r
397 crQUEUE_RECEIVE( xHandle, xCommsQueue, ( void * ) &cRxedChar, mainCOMMS_RX_DELAY, &xResult );
\r
399 /* Was the character recived (if any) the expected character. */
\r
400 if( ( cRxedChar != cExpectedChar ) || ( xResult != pdPASS ) )
\r
402 /* Got an unexpected character. This can sometimes occur when
\r
403 reseting the system using the debugger leaving characters already
\r
404 in the UART regsters. */
\r
405 uxErrorStatus = pdFAIL;
\r
407 /* Resync by waiting for the end of the current string. */
\r
408 while( cRxedChar != mainLAST_TX_CHAR )
\r
410 crQUEUE_RECEIVE( xHandle, xCommsQueue, ( void * ) &cRxedChar, mainCOMMS_RX_DELAY, &xResult );
\r
413 /* The next expected character is the start of the string again. */
\r
414 cExpectedChar = mainFIRST_TX_CHAR;
\r
418 if( cExpectedChar == mainLAST_TX_CHAR )
\r
420 /* We have reached the end of the string - we now expect to
\r
421 receive the first character in the string again. The LED is
\r
422 toggled to indicate that the entire string was received without
\r
424 vParTestToggleLED( mainCOMMS_RX_LED );
\r
425 cExpectedChar = mainFIRST_TX_CHAR;
\r
429 /* We got the expected character, we now expect to receive the
\r
430 next character in the string. */
\r
438 /*-----------------------------------------------------------*/
\r
440 static void vSerialTxCoRoutine( CoRoutineHandle_t xHandle, unsigned portBASE_TYPE uxIndex )
\r
442 portTickType xDelayPeriod;
\r
443 static unsigned long *pulRandomBytes = mainFIRST_PROGRAM_BYTES;
\r
445 /* Co-routine MUST start with a call to crSTART. */
\r
446 crSTART( xHandle );
\r
450 /* Was the previously transmitted string received correctly? */
\r
451 if( uxErrorStatus != pdPASS )
\r
453 /* An error was encountered so set the error LED. */
\r
457 /* The next character to Tx is the first in the string. */
\r
458 cNextChar = mainFIRST_TX_CHAR;
\r
460 UARTIntDisable( UART0_BASE, UART_INT_TX );
\r
462 /* Send the first character. */
\r
463 if( !( HWREG( UART0_BASE + UART_O_FR ) & UART_FR_TXFF ) )
\r
465 HWREG( UART0_BASE + UART_O_DR ) = cNextChar;
\r
468 /* Move the variable to the char to Tx on so the ISR transmits
\r
469 the next character in the string once this one has completed. */
\r
472 UARTIntEnable(UART0_BASE, UART_INT_TX);
\r
474 /* Toggle the LED to show a new string is being transmitted. */
\r
475 vParTestToggleLED( mainCOMMS_TX_LED );
\r
477 /* Delay before we start the string off again. A pseudo-random delay
\r
478 is used as this will provide a better test. */
\r
479 xDelayPeriod = xTaskGetTickCount() + ( *pulRandomBytes );
\r
482 if( pulRandomBytes > mainTOTAL_PROGRAM_MEMORY )
\r
484 pulRandomBytes = mainFIRST_PROGRAM_BYTES;
\r
487 /* Make sure we don't wait too long... */
\r
488 xDelayPeriod &= mainMAX_TX_DELAY;
\r
490 /* ...but we do want to wait. */
\r
491 if( xDelayPeriod < mainMIN_TX_DELAY )
\r
493 xDelayPeriod = mainMIN_TX_DELAY;
\r
496 /* Block for the random(ish) time. */
\r
497 crDELAY( xHandle, xDelayPeriod );
\r
500 /* Co-routine MUST end with a call to crEND. */
\r
503 /*-----------------------------------------------------------*/
\r
505 static void vSerialInit( void )
\r
507 /* Enable the UART. GPIOA has already been initialised. */
\r
508 SysCtlPeripheralEnable(SYSCTL_PERIPH_UART0);
\r
510 /* Set GPIO A0 and A1 as peripheral function. They are used to output the
\r
512 GPIODirModeSet( GPIO_PORTA_BASE, GPIO_PIN_0 | GPIO_PIN_1, GPIO_DIR_MODE_HW );
\r
514 /* Configure the UART for 8-N-1 operation. */
\r
515 UARTConfigSet( UART0_BASE, mainBAUD_RATE, UART_CONFIG_WLEN_8 | UART_CONFIG_PAR_NONE | UART_CONFIG_STOP_ONE );
\r
517 /* We dont want to use the fifo. This is for test purposes to generate
\r
518 as many interrupts as possible. */
\r
519 HWREG( UART0_BASE + UART_O_LCR_H ) &= ~mainFIFO_SET;
\r
521 /* Enable both Rx and Tx interrupts. */
\r
522 HWREG( UART0_BASE + UART_O_IM ) |= ( UART_INT_TX | UART_INT_RX );
\r
523 IntEnable( INT_UART0 );
\r
525 /*-----------------------------------------------------------*/
\r
527 void vUART_ISR(void)
\r
529 unsigned long ulStatus;
\r
531 portBASE_TYPE xTaskWokenByPost = pdFALSE;
\r
533 /* What caused the interrupt. */
\r
534 ulStatus = UARTIntStatus( UART0_BASE, pdTRUE );
\r
536 /* Clear the interrupt. */
\r
537 UARTIntClear( UART0_BASE, ulStatus );
\r
539 /* Was an Rx interrpt pending? */
\r
540 if( ulStatus & UART_INT_RX )
\r
542 if( ( HWREG(UART0_BASE + UART_O_FR ) & UART_FR_RXFF ) )
\r
544 /* Get the char from the buffer and post it onto the queue of
\r
545 Rxed chars. Posting the character should wake the task that is
\r
546 blocked on the queue waiting for characters. */
\r
547 cRxedChar = ( char ) HWREG( UART0_BASE + UART_O_DR );
\r
548 xTaskWokenByPost = crQUEUE_SEND_FROM_ISR( xCommsQueue, &cRxedChar, xTaskWokenByPost );
\r
552 /* Was a Tx interrupt pending? */
\r
553 if( ulStatus & UART_INT_TX )
\r
555 /* Send the next character in the string. We are not using the FIFO. */
\r
556 if( cNextChar <= mainLAST_TX_CHAR )
\r
558 if( !( HWREG( UART0_BASE + UART_O_FR ) & UART_FR_TXFF ) )
\r
560 HWREG( UART0_BASE + UART_O_DR ) = cNextChar;
\r
566 if( xTaskWokenByPost )
\r
568 /* We are posting to a co-routine rather than a task so don't bother
\r
569 causing a task switch. */
\r
572 /*-----------------------------------------------------------*/
\r
574 static void prvPDCWrite( char cAddress, char cData )
\r
578 PDCWrite( cAddress, cData );
\r
582 /*-----------------------------------------------------------*/
\r
584 void vSetErrorLED( void )
\r
586 vParTestSetLED( mainCOMMS_FAIL_LED, pdTRUE );
\r
588 /*-----------------------------------------------------------*/
\r
590 void prvSetAndCheckRegisters( void )
\r
592 /* Fill the general purpose registers with known values. */
\r
596 " add r0, r11, #1 \n"
\r
597 " add r1, r11, #2 \n"
\r
598 " add r2, r11, #3 \n"
\r
599 " add r3, r11, #4 \n"
\r
600 " add r4, r11, #5 \n"
\r
601 " add r5, r11, #6 \n"
\r
602 " add r6, r11, #7 \n"
\r
603 " add r7, r11, #8 \n"
\r
604 " add r8, r11, #9 \n"
\r
605 " add r9, r11, #10 \n"
\r
606 " add r10, r11, #11 \n"
\r
607 " add r12, r11, #12"
\r
610 /* Check the values are as expected. */
\r
614 " bne set_error_led \n"
\r
616 " bne set_error_led \n"
\r
618 " bne set_error_led \n"
\r
620 " bne set_error_led \n"
\r
622 " bne set_error_led \n"
\r
624 " bne set_error_led \n"
\r
626 " bne set_error_led \n"
\r
628 " bne set_error_led \n"
\r
630 " bne set_error_led \n"
\r
632 " bne set_error_led \n"
\r
634 " bne set_error_led \n"
\r
636 " bne set_error_led \n"
\r
638 " bne set_error_led \n"
\r
644 "set_error_led: \n"
\r
646 " ldr r1, vSetErrorLEDConst\n"
\r
652 "vSetErrorLEDConst: .word vSetErrorLED"
\r
655 /*-----------------------------------------------------------*/
\r