/* FreeRTOS V8.2.0rc1 - Copyright (C) 2014 Real Time Engineers Ltd. All rights reserved VISIT http://www.FreeRTOS.org TO ENSURE YOU ARE USING THE LATEST VERSION. 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. Full license text is available on the following link: http://www.freertos.org/a00114.html 1 tab == 4 spaces! *************************************************************************** * * * Having a problem? Start by reading the FAQ "My application does * * not run, what could be wrong?". Have you defined configASSERT()? * * * * http://www.FreeRTOS.org/FAQHelp.html * * * *************************************************************************** *************************************************************************** * * * FreeRTOS provides completely free yet professionally developed, * * robust, strictly quality controlled, supported, and cross * * platform software that is more than just the market leader, it * * is the industry's de facto standard. * * * * Help yourself get started quickly while simultaneously helping * * to support the FreeRTOS project by purchasing a FreeRTOS * * tutorial book, reference manual, or both: * * http://www.FreeRTOS.org/Documentation * * * *************************************************************************** *************************************************************************** * * * Investing in training allows your team to be as productive as * * possible as early as possible, lowering your overall development * * cost, and enabling you to bring a more robust product to market * * earlier than would otherwise be possible. Richard Barry is both * * the architect and key author of FreeRTOS, and so also the world's * * leading authority on what is the world's most popular real time * * kernel for deeply embedded MCU designs. Obtaining your training * * from Richard ensures your team will gain directly from his in-depth * * product knowledge and years of usage experience. Contact Real Time * * Engineers Ltd to enquire about the FreeRTOS Masterclass, presented * * by Richard Barry: http://www.FreeRTOS.org/contact * * *************************************************************************** *************************************************************************** * * * You are receiving this top quality software for free. Please play * * fair and reciprocate by reporting any suspected issues and * * participating in the community forum: * * http://www.FreeRTOS.org/support * * * * Thank you! * * * *************************************************************************** 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, a DOS compatible FAT file system, and our tiny thread aware UDP/IP stack. http://www.FreeRTOS.org/labs - Where new FreeRTOS products go to incubate. Come and try FreeRTOS+TCP, our new open source TCP/IP stack for FreeRTOS. http://www.OpenRTOS.com - Real Time Engineers ltd license FreeRTOS to High Integrity Systems ltd. to sell under the OpenRTOS brand. Low cost OpenRTOS licenses offer ticketed support, indemnification and commercial middleware. 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. 1 tab == 4 spaces! */ /* BASIC INTERRUPT DRIVEN SERIAL PORT DRIVER FOR DEMO PURPOSES */ #include #include "FreeRTOS.h" #include "queue.h" #include "task.h" #include "serial.h" /* Constants required to setup the serial control register. */ #define ser8_BIT_MODE ( ( unsigned char ) 0x40 ) #define serRX_ENABLE ( ( unsigned char ) 0x10 ) /* Constants to setup the timer used to generate the baud rate. */ #define serCLOCK_DIV_48 ( ( unsigned char ) 0x03 ) #define serUSE_PRESCALED_CLOCK ( ( unsigned char ) 0x10 ) #define ser8BIT_WITH_RELOAD ( ( unsigned char ) 0x20 ) #define serSMOD ( ( unsigned char ) 0x10 ) static QueueHandle_t xRxedChars; static QueueHandle_t xCharsForTx; data static unsigned portBASE_TYPE uxTxEmpty; /*-----------------------------------------------------------*/ xComPortHandle xSerialPortInitMinimal( unsigned long ulWantedBaud, unsigned portBASE_TYPE uxQueueLength ) { unsigned long ulReloadValue; const portFLOAT fBaudConst = ( portFLOAT ) configCPU_CLOCK_HZ * ( portFLOAT ) 2.0; unsigned char ucOriginalSFRPage; portENTER_CRITICAL(); { ucOriginalSFRPage = SFRPAGE; SFRPAGE = 0; uxTxEmpty = pdTRUE; /* Create the queues used by the com test task. */ xRxedChars = xQueueCreate( uxQueueLength, ( unsigned portBASE_TYPE ) sizeof( char ) ); xCharsForTx = xQueueCreate( uxQueueLength, ( unsigned portBASE_TYPE ) sizeof( char ) ); /* Calculate the baud rate to use timer 1. */ ulReloadValue = ( unsigned long ) ( ( ( portFLOAT ) 256 - ( fBaudConst / ( portFLOAT ) ( 32 * ulWantedBaud ) ) ) + ( portFLOAT ) 0.5 ); /* Set timer one for desired mode of operation. */ TMOD &= 0x08; TMOD |= ser8BIT_WITH_RELOAD; SSTA0 |= serSMOD; /* Set the reload and start values for the time. */ TL1 = ( unsigned char ) ulReloadValue; TH1 = ( unsigned char ) ulReloadValue; /* Setup the control register for standard n, 8, 1 - variable baud rate. */ SCON = ser8_BIT_MODE | serRX_ENABLE; /* Enable the serial port interrupts */ ES = 1; /* Start the timer. */ TR1 = 1; SFRPAGE = ucOriginalSFRPage; } portEXIT_CRITICAL(); /* Unlike some ports, this serial code does not allow for more than one com port. We therefore don't return a pointer to a port structure and can instead just return NULL. */ return NULL; } /*-----------------------------------------------------------*/ void vSerialISR( void ) interrupt 4 { char cChar; portBASE_TYPE xHigherPriorityTaskWoken = pdFALSE; /* 8051 port interrupt routines MUST be placed within a critical section if taskYIELD() is used within the ISR! */ portENTER_CRITICAL(); { if( RI ) { /* Get the character and post it on the queue of Rxed characters. If the post causes a task to wake force a context switch if the woken task has a higher priority than the task we have interrupted. */ cChar = SBUF; RI = 0; xQueueSendFromISR( xRxedChars, &cChar, &xHigherPriorityTaskWoken ); } if( TI ) { if( xQueueReceiveFromISR( xCharsForTx, &cChar, &xHigherPriorityTaskWoken ) == ( portBASE_TYPE ) pdTRUE ) { /* Send the next character queued for Tx. */ SBUF = cChar; } else { /* Queue empty, nothing to send. */ uxTxEmpty = pdTRUE; } TI = 0; } if( xHigherPriorityTaskWoken ) { portYIELD(); } } portEXIT_CRITICAL(); } /*-----------------------------------------------------------*/ portBASE_TYPE xSerialGetChar( xComPortHandle pxPort, signed char *pcRxedChar, TickType_t xBlockTime ) { /* There is only one port supported. */ ( 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 ( portBASE_TYPE ) pdTRUE; } else { return ( portBASE_TYPE ) pdFALSE; } } /*-----------------------------------------------------------*/ portBASE_TYPE xSerialPutChar( xComPortHandle pxPort, signed char cOutChar, TickType_t xBlockTime ) { portBASE_TYPE xReturn; /* There is only one port supported. */ ( void ) pxPort; portENTER_CRITICAL(); { if( uxTxEmpty == pdTRUE ) { SBUF = cOutChar; uxTxEmpty = pdFALSE; xReturn = ( portBASE_TYPE ) pdTRUE; } else { xReturn = xQueueSend( xCharsForTx, &cOutChar, xBlockTime ); if( xReturn == ( portBASE_TYPE ) pdFALSE ) { xReturn = ( portBASE_TYPE ) pdTRUE; } } } portEXIT_CRITICAL(); return xReturn; } /*-----------------------------------------------------------*/ void vSerialClose( xComPortHandle xPort ) { /* Not implemented in this port. */ ( void ) xPort; } /*-----------------------------------------------------------*/