/* | |
FreeRTOS V7.4.1 - 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. | |
NOTE: This driver is primarily to test the scheduler functionality. It does | |
not effectively use the buffers or DMA and is therefore not intended to be | |
an example of an efficient driver. */ | |
/* Standard include file. */ | |
#include <stdlib.h> | |
#include <plib.h> | |
/* Scheduler include files. */ | |
#include "FreeRTOS.h" | |
#include "queue.h" | |
#include "task.h" | |
/* Demo app include files. */ | |
#include "serial.h" | |
/* Hardware setup. */ | |
#define serSET_FLAG ( 1 ) | |
/* The queues used to communicate between tasks and ISR's. */ | |
static xQueueHandle xRxedChars; | |
static xQueueHandle xCharsForTx; | |
/* Flag used to indicate the tx status. */ | |
static portBASE_TYPE xTxHasEnded; | |
/*-----------------------------------------------------------*/ | |
/* The UART interrupt handler. As this uses the FreeRTOS assembly interrupt | |
entry point the IPL setting in the following prototype has no effect. The | |
interrupt priority is set by the call to ConfigIntUART2() in | |
xSerialPortInitMinimal(). */ | |
void __attribute__( (interrupt(ipl0), vector(_UART2_VECTOR))) vU2InterruptWrapper( void ); | |
/*-----------------------------------------------------------*/ | |
xComPortHandle xSerialPortInitMinimal( unsigned long ulWantedBaud, unsigned portBASE_TYPE uxQueueLength ) | |
{ | |
unsigned short usBRG; | |
/* Create the queues used by the com test task. */ | |
xRxedChars = xQueueCreate( uxQueueLength, ( unsigned portBASE_TYPE ) sizeof( signed char ) ); | |
xCharsForTx = xQueueCreate( uxQueueLength, ( unsigned portBASE_TYPE ) sizeof( signed char ) ); | |
/* Configure the UART and interrupts. */ | |
usBRG = (unsigned short)(( (float)configPERIPHERAL_CLOCK_HZ / ( (float)16 * (float)ulWantedBaud ) ) - (float)0.5); | |
OpenUART2( UART_EN, UART_RX_ENABLE | UART_TX_ENABLE | UART_INT_TX | UART_INT_RX_CHAR, usBRG ); | |
ConfigIntUART2( ( configKERNEL_INTERRUPT_PRIORITY + 1 ) | UART_INT_SUB_PR0 | UART_TX_INT_EN | UART_RX_INT_EN ); | |
xTxHasEnded = pdTRUE; | |
/* Only a single port is implemented so we don't need to return anything. */ | |
return NULL; | |
} | |
/*-----------------------------------------------------------*/ | |
signed portBASE_TYPE xSerialGetChar( xComPortHandle pxPort, signed char *pcRxedChar, portTickType xBlockTime ) | |
{ | |
/* Only one port is 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 pdTRUE; | |
} | |
else | |
{ | |
return pdFALSE; | |
} | |
} | |
/*-----------------------------------------------------------*/ | |
signed portBASE_TYPE xSerialPutChar( xComPortHandle pxPort, signed char cOutChar, portTickType xBlockTime ) | |
{ | |
/* Only one port is supported. */ | |
( void ) pxPort; | |
/* Return false if after the block time there is no room on the Tx queue. */ | |
if( xQueueSend( xCharsForTx, &cOutChar, xBlockTime ) != pdPASS ) | |
{ | |
return pdFAIL; | |
} | |
/* A critical section should not be required as xTxHasEnded will not be | |
written to by the ISR if it is already 0 (is this correct?). */ | |
if( xTxHasEnded ) | |
{ | |
xTxHasEnded = pdFALSE; | |
IFS1SET = _IFS1_U2TXIF_MASK; | |
} | |
return pdPASS; | |
} | |
/*-----------------------------------------------------------*/ | |
void vSerialClose( xComPortHandle xPort ) | |
{ | |
} | |
/*-----------------------------------------------------------*/ | |
void vU2InterruptHandler( void ) | |
{ | |
/* Declared static to minimise stack use. */ | |
static char cChar; | |
static portBASE_TYPE xHigherPriorityTaskWoken; | |
xHigherPriorityTaskWoken = pdFALSE; | |
/* Are any Rx interrupts pending? */ | |
if( IFS1bits.U2RXIF == 1) | |
{ | |
while( U2STAbits.URXDA ) | |
{ | |
/* Retrieve the received character and place it in the queue of | |
received characters. */ | |
cChar = U2RXREG; | |
xQueueSendFromISR( xRxedChars, &cChar, &xHigherPriorityTaskWoken ); | |
} | |
IFS1CLR = _IFS1_U2RXIF_MASK; | |
} | |
/* Are any Tx interrupts pending? */ | |
if( IFS1bits.U2TXIF == 1 ) | |
{ | |
while( !( U2STAbits.UTXBF ) ) | |
{ | |
if( xQueueReceiveFromISR( xCharsForTx, &cChar, &xHigherPriorityTaskWoken ) == pdTRUE ) | |
{ | |
/* Send the next character queued for Tx. */ | |
U2TXREG = cChar; | |
} | |
else | |
{ | |
/* Queue empty, nothing to send. */ | |
xTxHasEnded = pdTRUE; | |
break; | |
} | |
} | |
IFS1CLR = _IFS1_U2TXIF_MASK; | |
} | |
/* If sending or receiving necessitates a context switch, then switch now. */ | |
portEND_SWITCHING_ISR( xHigherPriorityTaskWoken ); | |
} | |