git.sur5r.net Git - freertos/blob - FreeRTOS/Demo/PIC18_WizC/serial/isrSerialRx.c

   1 /*\r
   2     FreeRTOS V8.0.0 - Copyright (C) 2014 Real Time Engineers Ltd. \r
   3     All rights reserved\r
   4 \r
   5     VISIT http://www.FreeRTOS.org TO ENSURE YOU ARE USING THE LATEST VERSION.\r
   6 \r
   7     ***************************************************************************\r
   8      *                                                                       *\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
  12      *                                                                       *\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
  16      *                                                                       *\r
  17      *    Thank you!                                                         *\r
  18      *                                                                       *\r
  19     ***************************************************************************\r
  20 \r
  21     This file is part of the FreeRTOS distribution.\r
  22 \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
  26 \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
  30     >>! kernel.\r
  31 \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
  36 \r
  37     1 tab == 4 spaces!\r
  38 \r
  39     ***************************************************************************\r
  40      *                                                                       *\r
  41      *    Having a problem?  Start by reading the FAQ "My application does   *\r
  42      *    not run, what could be wrong?"                                     *\r
  43      *                                                                       *\r
  44      *    http://www.FreeRTOS.org/FAQHelp.html                               *\r
  45      *                                                                       *\r
  46     ***************************************************************************\r
  47 \r
  48     http://www.FreeRTOS.org - Documentation, books, training, latest versions,\r
  49     license and Real Time Engineers Ltd. contact details.\r
  50 \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
  54 \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
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  58 \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
  62 \r
  63     1 tab == 4 spaces!\r
  64 */\r
  65 \r
  66 /*\r
  67 Changes from V3.0.0\r
  68         + ISRcode pulled inline to reduce stack-usage.\r
  69 \r
  70         + Added functionality to only call vTaskSwitchContext() once\r
  71           when handling multiple interruptsources in a single interruptcall.\r
  72 \r
  73         + Filename changed to a .c extension to allow stepping through code\r
  74           using F7.\r
  75 \r
  76 Changes from V3.0.1\r
  77 */\r
  78 \r
  79 #ifndef _FREERTOS_SERIAL_ISRSERIALRX_C\r
  80 #define _FREERTOS_SERIAL_ISRSERIALRX_C\r
  81 \r
  82 #define serCONTINUOUS_RX                ( 1 )\r
  83 #define serCLEAR_OVERRUN                ( 0 )\r
  84 \r
  85 {\r
  86         /*\r
  87          * Was the interrupt a byte being received?\r
  88          */\r
  89         if( bRCIF && bRCIE)\r
  90         {\r
  91                 /*\r
  92                  * Queue to interface between comms API and interrupt routine.\r
  93                 */\r
  94                 extern QueueHandle_t xRxedChars;\r
  95                 \r
  96                 /*\r
  97                  * Because we are not allowed to use local variables here,\r
  98                  * PRODL is (ab)used as temporary storage.  This is allowed\r
  99                  * because this SFR will be restored before exiting the ISR.\r
 100                  */\r
 101                 extern char                     cChar;\r
 102                 extern portBASE_TYPE xHigherPriorityTaskWoken;\r
 103                 #pragma locate cChar    &PRODL\r
 104 \r
 105                 /*\r
 106                  * If there was a framing error, just get and ignore\r
 107                  * the character\r
 108                  */\r
 109                 if( bFERR )\r
 110                 {\r
 111                         cChar = RCREG;\r
 112                 }\r
 113                 else\r
 114                 {\r
 115                         /*\r
 116                          * Get the character and post it on the queue of Rxed\r
 117                          * characters. If the post causes a task to wake ask\r
 118                          * for a context switch as the woken task may have a\r
 119                          * higher priority than the task we have interrupted.\r
 120                          */\r
 121                         cChar = RCREG;\r
 122 \r
 123                         /*\r
 124                          * Clear any overrun errors.\r
 125                          */\r
 126                         if( bOERR )\r
 127                         {\r
 128                                 bCREN = serCLEAR_OVERRUN;\r
 129                                 bCREN = serCONTINUOUS_RX;       \r
 130                         }\r
 131 \r
 132                         xHigherPriorityTaskWoken = pdFALSE;\r
 133                         xQueueSendFromISR( xRxedChars, ( const void * ) &cChar, &xHigherPriorityTaskWoken );\r
 134 \r
 135                         if( xHigherPriorityTaskWoken )\r
 136                         {\r
 137                                 uxSwitchRequested = pdTRUE;\r
 138                         }\r
 139                 }\r
 140         }\r
 141 }\r
 142 \r
 143 #endif  /* _FREERTOS_SERIAL_ISRSERIALRX_C */\r