/* | |
FreeRTOS.org V5.4.0 - Copyright (C) 2003-2009 Richard Barry. | |
This file is part of the FreeRTOS.org distribution. | |
FreeRTOS.org 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 exception to the GPL is included to allow you to distribute a | |
combined work that includes FreeRTOS.org without being obliged to provide | |
the source code for any proprietary components. Alternative commercial | |
license and support terms are also available upon request. See the | |
licensing section of http://www.FreeRTOS.org for full details. | |
FreeRTOS.org 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 along | |
with FreeRTOS.org; if not, write to the Free Software Foundation, Inc., 59 | |
Temple Place, Suite 330, Boston, MA 02111-1307 USA. | |
*************************************************************************** | |
* * | |
* Get the FreeRTOS eBook! See http://www.FreeRTOS.org/Documentation * | |
* * | |
* This is a concise, step by step, 'hands on' guide that describes both * | |
* general multitasking concepts and FreeRTOS specifics. It presents and * | |
* explains numerous examples that are written using the FreeRTOS API. * | |
* Full source code for all the examples is provided in an accompanying * | |
* .zip file. * | |
* * | |
*************************************************************************** | |
1 tab == 4 spaces! | |
Please ensure to read the configuration and relevant port sections of the | |
online documentation. | |
http://www.FreeRTOS.org - Documentation, latest information, license and | |
contact details. | |
http://www.SafeRTOS.com - A version that is certified for use in safety | |
critical systems. | |
http://www.OpenRTOS.com - Commercial support, development, porting, | |
licensing and training services. | |
*/ | |
/* BASIC INTERRUPT DRIVEN SERIAL PORT DRIVER for port 1. | |
Note that this driver is written to test the RTOS port and is not intended | |
to represent an optimised solution. */ | |
/* Processor Expert generated includes. */ | |
#include "com0.h" | |
/* Scheduler include files. */ | |
#include "FreeRTOS.h" | |
#include "queue.h" | |
#include "task.h" | |
/* Demo application include files. */ | |
#include "serial.h" | |
/* The queues used to communicate between the task code and the interrupt | |
service routines. */ | |
static xQueueHandle xRxedChars; | |
static xQueueHandle xCharsForTx; | |
/* Interrupt identification bits. */ | |
#define serOVERRUN_INTERRUPT ( 0x08 ) | |
#define serRX_INTERRUPT ( 0x20 ) | |
#define serTX_INTERRUPT ( 0x80 ) | |
/*-----------------------------------------------------------*/ | |
/* | |
* Initialise port for interrupt driven communications. | |
*/ | |
xComPortHandle xSerialPortInitMinimal( unsigned portLONG ulWantedBaud, unsigned portBASE_TYPE uxQueueLength ) | |
{ | |
/* Hardware setup is performed by the Processor Expert generated code. | |
This function just creates the queues used to communicate between the | |
interrupt code and the task code - then sets the required baud rate. */ | |
xRxedChars = xQueueCreate( uxQueueLength, ( unsigned portBASE_TYPE ) sizeof( signed portCHAR ) ); | |
xCharsForTx = xQueueCreate( uxQueueLength, ( unsigned portBASE_TYPE ) sizeof( signed portCHAR ) ); | |
COM0_SetBaudRateMode( ( portCHAR ) ulWantedBaud ); | |
return NULL; | |
} | |
/*-----------------------------------------------------------*/ | |
signed portBASE_TYPE xSerialGetChar( xComPortHandle pxPort, signed portCHAR *pcRxedChar, portTickType xBlockTime ) | |
{ | |
/* Get the next character from the buffer queue. Return false if no characters | |
are available, or arrive before xBlockTime expires. */ | |
if( xQueueReceive( xRxedChars, pcRxedChar, xBlockTime ) ) | |
{ | |
return pdTRUE; | |
} | |
else | |
{ | |
return pdFALSE; | |
} | |
} | |
/*-----------------------------------------------------------*/ | |
signed portBASE_TYPE xSerialPutChar( xComPortHandle pxPort, signed portCHAR cOutChar, portTickType xBlockTime ) | |
{ | |
/* Place the character in the queue of characters to be transmitted. */ | |
if( xQueueSend( xCharsForTx, &cOutChar, xBlockTime ) != pdPASS ) | |
{ | |
return pdFAIL; | |
} | |
/* Turn on the Tx interrupt so the ISR will remove the character from the | |
queue and send it. This does not need to be in a critical section as | |
if the interrupt has already removed the character the next interrupt | |
will simply turn off the Tx interrupt again. */ | |
SCI0CR2_SCTIE = 1;; | |
return pdPASS; | |
} | |
/*-----------------------------------------------------------*/ | |
void vSerialClose( xComPortHandle xPort ) | |
{ | |
/* Not supported. */ | |
( void ) xPort; | |
} | |
/*-----------------------------------------------------------*/ | |
/* | |
* Interrupt service routine for the serial port. Must be in non-banked | |
* memory. | |
*/ | |
#pragma CODE_SEG __NEAR_SEG NON_BANKED | |
__interrupt void vCOM0_ISR( void ) | |
{ | |
volatile unsigned portCHAR ucByte, ucStatus; | |
portBASE_TYPE xHigherPriorityTaskWoken = pdFALSE; | |
/* What caused the interrupt? */ | |
ucStatus = SCI0SR1; | |
if( ucStatus & serOVERRUN_INTERRUPT ) | |
{ | |
/* The interrupt was caused by an overrun. Clear the error by reading | |
the data register. */ | |
ucByte = SCI0DRL; | |
} | |
if( ucStatus & serRX_INTERRUPT ) | |
{ | |
/* The interrupt was caused by a character being received. | |
Read the received byte. */ | |
ucByte = SCI0DRL; | |
/* Post the character onto the queue of received characters - noting | |
whether or not this wakes a task. */ | |
xQueueSendFromISR( xRxedChars, ( void * ) &ucByte, &xHigherPriorityTaskWoken ); | |
} | |
if( ( ucStatus & serTX_INTERRUPT ) && ( SCI0CR2_SCTIE ) ) | |
{ | |
/* The interrupt was caused by a character being transmitted. */ | |
if( xQueueReceiveFromISR( xCharsForTx, ( void * ) &ucByte, &xHigherPriorityTaskWoken ) == pdTRUE ) | |
{ | |
/* Clear the SCRF bit. */ | |
SCI0DRL = ucByte; | |
} | |
else | |
{ | |
/* Disable transmit interrupt */ | |
SCI0CR2_SCTIE = 0; | |
} | |
} | |
if( xHigherPriorityTaskWoken ) | |
{ | |
portYIELD(); | |
} | |
} | |
#pragma CODE_SEG DEFAULT | |