| /* | |
| FreeRTOS V7.4.2 - Copyright (C) 2013 Real Time Engineers Ltd. | |
| FEATURES AND PORTS ARE ADDED TO FREERTOS ALL THE TIME. PLEASE VISIT | |
| http://www.FreeRTOS.org TO ENSURE YOU ARE USING THE LATEST VERSION. | |
| *************************************************************************** | |
| * * | |
| * FreeRTOS tutorial books are available in pdf and paperback. * | |
| * Complete, revised, and edited pdf reference manuals are also * | |
| * available. * | |
| * * | |
| * Purchasing FreeRTOS documentation will not only help you, by * | |
| * ensuring you get running as quickly as possible and with an * | |
| * in-depth knowledge of how to use FreeRTOS, it will also help * | |
| * the FreeRTOS project to continue with its mission of providing * | |
| * professional grade, cross platform, de facto standard solutions * | |
| * for microcontrollers - completely free of charge! * | |
| * * | |
| * >>> See http://www.FreeRTOS.org/Documentation for details. <<< * | |
| * * | |
| * Thank you for using FreeRTOS, and thank you for your support! * | |
| * * | |
| *************************************************************************** | |
| This file is part of the FreeRTOS distribution. | |
| FreeRTOS is free software; you can redistribute it and/or modify it under | |
| the terms of the GNU General Public License (version 2) as published by the | |
| Free Software Foundation AND MODIFIED BY the FreeRTOS exception. | |
| >>>>>>NOTE<<<<<< The modification to the GPL is included to allow you to | |
| distribute a combined work that includes FreeRTOS without being obliged to | |
| provide the source code for proprietary components outside of the FreeRTOS | |
| kernel. | |
| FreeRTOS is distributed in the hope that it will be useful, but WITHOUT ANY | |
| WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS | |
| FOR A PARTICULAR PURPOSE. See the GNU General Public License for more | |
| details. You should have received a copy of the GNU General Public License | |
| and the FreeRTOS license exception along with FreeRTOS; if not it can be | |
| viewed here: http://www.freertos.org/a00114.html and also obtained by | |
| writing to Real Time Engineers Ltd., contact details for whom are available | |
| on the FreeRTOS WEB site. | |
| 1 tab == 4 spaces! | |
| *************************************************************************** | |
| * * | |
| * Having a problem? Start by reading the FAQ "My application does * | |
| * not run, what could be wrong?" * | |
| * * | |
| * http://www.FreeRTOS.org/FAQHelp.html * | |
| * * | |
| *************************************************************************** | |
| http://www.FreeRTOS.org - Documentation, books, training, latest versions, | |
| license and Real Time Engineers Ltd. contact details. | |
| http://www.FreeRTOS.org/plus - A selection of FreeRTOS ecosystem products, | |
| including FreeRTOS+Trace - an indispensable productivity tool, and our new | |
| fully thread aware and reentrant UDP/IP stack. | |
| http://www.OpenRTOS.com - Real Time Engineers ltd license FreeRTOS to High | |
| Integrity Systems, who sell the code with commercial support, | |
| indemnification and middleware, under the OpenRTOS brand. | |
| http://www.SafeRTOS.com - High Integrity Systems also provide a safety | |
| engineered and independently SIL3 certified version for use in safety and | |
| mission critical applications that require provable dependability. | |
| */ | |
| /* | |
| BASIC INTERRUPT DRIVEN SERIAL PORT DRIVER FOR UART0. | |
| ***Note*** This example uses queues to send each character into an interrupt | |
| service routine and out of an interrupt service routine individually. This | |
| is done to demonstrate queues being used in an interrupt, and to deliberately | |
| load the system to test the FreeRTOS port. It is *NOT* meant to be an | |
| example of an efficient implementation. An efficient implementation should | |
| use FIFO's or DMA if available, and only use FreeRTOS API functions when | |
| enough has been received to warrant a task being unblocked to process the | |
| data. | |
| */ | |
| /* Scheduler includes. */ | |
| #include "FreeRTOS.h" | |
| #include "queue.h" | |
| #include "semphr.h" | |
| #include "comtest2.h" | |
| /* Library includes. */ | |
| #include "stm32l152_eval.h" | |
| /* Demo application includes. */ | |
| #include "serial.h" | |
| /*-----------------------------------------------------------*/ | |
| /* Misc defines. */ | |
| #define serINVALID_QUEUE ( ( xQueueHandle ) 0 ) | |
| #define serNO_BLOCK ( ( portTickType ) 0 ) | |
| /*-----------------------------------------------------------*/ | |
| /* The queue used to hold received characters. */ | |
| static xQueueHandle xRxedChars; | |
| static xQueueHandle xCharsForTx; | |
| /*-----------------------------------------------------------*/ | |
| /* | |
| * See the serial2.h header file. | |
| */ | |
| xComPortHandle xSerialPortInitMinimal( unsigned portLONG ulWantedBaud, unsigned portBASE_TYPE uxQueueLength ) | |
| { | |
| USART_InitTypeDef USART_InitStructure; | |
| xComPortHandle xReturn; | |
| NVIC_InitTypeDef NVIC_InitStructure; | |
| /* Create the queues used to hold Rx/Tx characters. */ | |
| xRxedChars = xQueueCreate( uxQueueLength, ( unsigned portBASE_TYPE ) sizeof( signed portCHAR ) ); | |
| xCharsForTx = xQueueCreate( uxQueueLength + 1, ( unsigned portBASE_TYPE ) sizeof( signed portCHAR ) ); | |
| /* If the queues were created correctly then setup the serial port | |
| hardware. */ | |
| if( ( xRxedChars != serINVALID_QUEUE ) && ( xCharsForTx != serINVALID_QUEUE ) ) | |
| { | |
| USART_InitStructure.USART_BaudRate = ulWantedBaud; | |
| USART_InitStructure.USART_WordLength = USART_WordLength_8b; | |
| USART_InitStructure.USART_StopBits = USART_StopBits_1; | |
| USART_InitStructure.USART_Parity = USART_Parity_No; | |
| USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None; | |
| USART_InitStructure.USART_Mode = USART_Mode_Rx | USART_Mode_Tx; | |
| /* The Eval board COM2 is being used, which in reality is the STM32 | |
| USART3. */ | |
| STM_EVAL_COMInit( COM2, &USART_InitStructure ); | |
| NVIC_InitStructure.NVIC_IRQChannel = USART3_IRQn; | |
| NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = configLIBRARY_MAX_SYSCALL_INTERRUPT_PRIORITY; | |
| NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0; /* Not used as 4 bits are used for the pre-emption priority. */; | |
| NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE; | |
| NVIC_Init( &NVIC_InitStructure ); | |
| USART_ITConfig( USART3, USART_IT_RXNE, ENABLE ); | |
| } | |
| else | |
| { | |
| xReturn = ( xComPortHandle ) 0; | |
| } | |
| /* This demo file only supports a single port but we have to return | |
| something to comply with the standard demo header file. */ | |
| return xReturn; | |
| } | |
| /*-----------------------------------------------------------*/ | |
| signed portBASE_TYPE xSerialGetChar( xComPortHandle pxPort, signed portCHAR *pcRxedChar, portTickType xBlockTime ) | |
| { | |
| /* The port handle is not required as this driver only supports one port. */ | |
| ( void ) pxPort; | |
| /* Get the next character from the buffer. Return false if no characters | |
| are available, or arrive before xBlockTime expires. */ | |
| if( xQueueReceive( xRxedChars, pcRxedChar, xBlockTime ) ) | |
| { | |
| return pdTRUE; | |
| } | |
| else | |
| { | |
| return pdFALSE; | |
| } | |
| } | |
| /*-----------------------------------------------------------*/ | |
| void vSerialPutString( xComPortHandle pxPort, const signed portCHAR * const pcString, unsigned portSHORT usStringLength ) | |
| { | |
| signed portCHAR *pxNext; | |
| /* A couple of parameters that this port does not use. */ | |
| ( void ) usStringLength; | |
| ( void ) pxPort; | |
| /* NOTE: This implementation does not handle the queue being full as no | |
| block time is used! */ | |
| /* The port handle is not required as this driver only supports UART1. */ | |
| ( void ) pxPort; | |
| /* Send each character in the string, one at a time. */ | |
| pxNext = ( signed portCHAR * ) pcString; | |
| while( *pxNext ) | |
| { | |
| xSerialPutChar( pxPort, *pxNext, serNO_BLOCK ); | |
| pxNext++; | |
| } | |
| } | |
| /*-----------------------------------------------------------*/ | |
| signed portBASE_TYPE xSerialPutChar( xComPortHandle pxPort, signed portCHAR cOutChar, portTickType xBlockTime ) | |
| { | |
| signed portBASE_TYPE xReturn; | |
| if( xQueueSend( xCharsForTx, &cOutChar, xBlockTime ) == pdPASS ) | |
| { | |
| xReturn = pdPASS; | |
| USART_ITConfig( USART3, USART_IT_TXE, ENABLE ); | |
| } | |
| else | |
| { | |
| xReturn = pdFAIL; | |
| } | |
| return xReturn; | |
| } | |
| /*-----------------------------------------------------------*/ | |
| void vSerialClose( xComPortHandle xPort ) | |
| { | |
| /* Not supported as not required by the demo application. */ | |
| } | |
| /*-----------------------------------------------------------*/ | |
| void USART3_IRQHandler( void ) | |
| { | |
| portBASE_TYPE xHigherPriorityTaskWoken = pdFALSE; | |
| portCHAR cChar; | |
| if( USART_GetITStatus( USART3, USART_IT_TXE ) == SET ) | |
| { | |
| /* The interrupt was caused by the TX register becoming empty. Are | |
| there any more characters to transmit? */ | |
| if( xQueueReceiveFromISR( xCharsForTx, &cChar, &xHigherPriorityTaskWoken ) == pdTRUE ) | |
| { | |
| /* A character was retrieved from the queue so can be sent to the | |
| USART now. */ | |
| USART_SendData( USART3, cChar ); | |
| } | |
| else | |
| { | |
| USART_ITConfig( USART3, USART_IT_TXE, DISABLE ); | |
| } | |
| } | |
| if( USART_GetITStatus( USART3, USART_IT_RXNE ) == SET ) | |
| { | |
| /* A character has been received on the USART, send it to the Rx | |
| handler task. */ | |
| cChar = USART_ReceiveData( USART3 ); | |
| xQueueSendFromISR( xRxedChars, &cChar, &xHigherPriorityTaskWoken ); | |
| } | |
| /* If sending or receiving from a queue has caused a task to unblock, and | |
| the unblocked task has a priority equal to or higher than the currently | |
| running task (the task this ISR interrupted), then xHigherPriorityTaskWoken | |
| will have automatically been set to pdTRUE within the queue send or receive | |
| function. portEND_SWITCHING_ISR() will then ensure that this ISR returns | |
| directly to the higher priority unblocked task. */ | |
| portEND_SWITCHING_ISR( xHigherPriorityTaskWoken ); | |
| } | |