/* | |
FreeRTOS V6.0.2 - Copyright (C) 2010 Real Time Engineers Ltd. | |
*************************************************************************** | |
* * | |
* If you are: * | |
* * | |
* + New to FreeRTOS, * | |
* + Wanting to learn FreeRTOS or multitasking in general quickly * | |
* + Looking for basic training, * | |
* + Wanting to improve your FreeRTOS skills and productivity * | |
* * | |
* then take a look at the FreeRTOS eBook * | |
* * | |
* "Using the FreeRTOS Real Time Kernel - a Practical Guide" * | |
* http://www.FreeRTOS.org/Documentation * | |
* * | |
* A pdf reference manual is also available. Both are usually delivered * | |
* to your inbox within 20 minutes to two hours when purchased between 8am * | |
* and 8pm GMT (although please allow up to 24 hours in case of * | |
* exceptional circumstances). 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 exception 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 Richard Barry, contact details for whom are available on the | |
FreeRTOS WEB site. | |
1 tab == 4 spaces! | |
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 long 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 char ) ); | |
xCharsForTx = xQueueCreate( uxQueueLength, ( unsigned portBASE_TYPE ) sizeof( signed char ) ); | |
COM0_SetBaudRateMode( ( char ) ulWantedBaud ); | |
return NULL; | |
} | |
/*-----------------------------------------------------------*/ | |
signed portBASE_TYPE xSerialGetChar( xComPortHandle pxPort, signed char *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 char 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 char 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 | |