serial.c

new freertos source code V5.0.3

/*
	FreeRTOS.org V5.0.3 - Copyright (C) 2003-2008 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 as published by
	the Free Software Foundation; either version 2 of the License, or
	(at your option) any later version.

	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

	A special exception to the GPL can be applied should you wish to distribute
	a combined work that includes FreeRTOS.org, without being obliged to provide
	the source code for any proprietary components.  See the licensing section 
	of http://www.FreeRTOS.org for full details of how and when the exception
	can be applied.

    ***************************************************************************
    ***************************************************************************
    *                                                                         *
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    * and even write all or part of your application on your behalf.          *
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    ***************************************************************************

	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.

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*/

/*
Changes from V1.00:
	
	+ Call to the more efficient portSWITCH_CONTEXT() replaces the call to 
	  taskYIELD() in the ISR.

Changes from V1.01:

	+ The semaphore task is not operational.  This does nothing but check
	  the semaphore from ISR functionality.
	+ ISR modified slightly so only Rx or Tx is serviced per ISR - not both.

Changes from V1.2.0:

	+ Change so Tx uses a DMA channel, and Rx uses an interrupt.

Changes from V1.2.3

	+ The function xPortInitMinimal() has been renamed to 
	  xSerialPortInitMinimal() and the function xPortInit() has been renamed
	  to xSerialPortInit().

Changes from V1.2.5

	+ Reverted back to the non-DMA serial port driver, with a slightly modified
	  ISR.  This is a better test of the scheduler mechanisms.
	+ A critical section is now used in vInterruptOn().
	+ Flag sTxInterruptOn has been added to the port structure.  This allows
	  checking of the interrupt enable status without performing any IO.

Changes from V2.0.0

	+ Use portTickType in place of unsigned pdLONG for delay periods.
	+ Slightly more efficient vSerialSendString() implementation.
	+ cQueueReieveFromISR() used in place of xQueueReceive() in ISR.
*/

#include <stdlib.h>
#include <dos.h>
#include "FreeRTOS.h"
#include "queue.h"
#include "task.h"
#include "portasm.h"
#include "semphr.h"

#define serMAX_PORTS			( ( unsigned portSHORT ) 2 )

#define serPORT_0_INT_REG		( 0xff44 )
#define serPORT_0_BAUD_REG		( 0xff88 )
#define serPORT_0_RX_REG		( 0xff86 )
#define serPORT_0_TX_REG		( 0xff84 )
#define serPORT_0_STATUS_REG	( 0xff82 )
#define serPORT_0_CTRL_REG		( 0xff80 )
#define serPORT_0_IRQ			( 0x14 )

#define serPORT_1_INT_REG		( 0xff42 )
#define serPORT_1_BAUD_REG		( 0xff18 )
#define serPORT_1_RX_REG		( 0xff16 )
#define serPORT_1_TX_REG		( 0xff14 )
#define serPORT_1_STATUS_REG	( 0xff12 )
#define serPORT_1_CTRL_REG		( 0xff10 )
#define serPORT_1_IRQ			( 0x11 )

#define serTX_EMPTY				( ( unsigned portSHORT ) 0x40 )
#define serRX_READY				( ( unsigned portSHORT ) 0x80 )

#define serRESET_PIC( usEOI_TYPE )	portOUTPUT_WORD( ( unsigned portSHORT ) 0xff22, usEOI_TYPE )
#define serTX_HOLD_EMPTY_INT		( ( unsigned portSHORT ) 0x100 )

#define serENABLE_INTERRUPTS		( ( unsigned portSHORT ) 0x80 )
#define serMODE						( ( unsigned portSHORT ) 0x01 )
#define serENABLE_TX_MACHINES		( ( unsigned portSHORT ) 0x40 )
#define serENABLE_RX_MACHINES		( ( unsigned portSHORT ) 0x20 )
#define serINTERRUPT_MASK			( ( unsigned portSHORT ) 0x08 )
#define serCLEAR_ALL_STATUS_BITS	( ( unsigned portSHORT ) 0x00 )
#define serINTERRUPT_PRIORITY		( ( unsigned portSHORT ) 0x01 ) /*< Just below the scheduler priority. */

#define serDONT_BLOCK				( ( portTickType ) 0 )

typedef enum
{ 
	serCOM1 = 0, 
	serCOM2, 
	serCOM3, 
	serCOM4, 
	serCOM5, 
	serCOM6, 
	serCOM7, 
	serCOM8 
} eCOMPort;

typedef enum 
{ 
	serNO_PARITY, 
	serODD_PARITY, 
	serEVEN_PARITY, 
	serMARK_PARITY, 
	serSPACE_PARITY 
} eParity;

typedef enum 
{ 
	serSTOP_1, 
	serSTOP_2 
} eStopBits;

typedef enum 
{ 
	serBITS_5, 
	serBITS_6, 
	serBITS_7, 
	serBITS_8 
} eDataBits;

typedef enum 
{ 
	ser50 = 0,
	ser75,		
	ser110,		
	ser134,		
	ser150,    
	ser200,
	ser300,		
	ser600,		
	ser1200,	
	ser1800,	
	ser2400,   
	ser4800,
	ser9600,		
	ser19200,	
	ser38400,	
	ser57600,	
	ser115200
} eBaud;

/* Must be same order as eBaud definitions. */
static const unsigned portSHORT usBaudRateDivisor[] = 
{
	0, /* Not sure if the first 6 are correct.  First cannot be used. */
	29127,
	19859,
	16302,
	14564,
	10923,	
	6879,
	3437,
	1718,
	1145,
	859,
	429,
	214,
	107,
	54,
	35,
	18
};


typedef struct xCOM_PORT
{
	/* Hardware parameters for this port. */
	portSHORT sTxInterruptOn;
	unsigned portSHORT usIntReg;
	unsigned portSHORT usBaudReg;
	unsigned portSHORT usRxReg;
	unsigned portSHORT usTxReg;
	unsigned portSHORT usStatusReg;
	unsigned portSHORT usCtrlReg;

	unsigned portSHORT usIRQVector;

	/* Queues used for communications with com test task. */
	xQueueHandle xRxedChars; 
	xQueueHandle xCharsForTx;

	/* This semaphore does nothing useful except test a feature of the
	scheduler. */
	xSemaphoreHandle xTestSem;

} xComPort;

static xComPort xPorts[ serMAX_PORTS ] = 
{
	{ pdFALSE, serPORT_0_INT_REG, serPORT_0_BAUD_REG, serPORT_0_RX_REG, serPORT_0_TX_REG, serPORT_0_STATUS_REG, serPORT_0_CTRL_REG, serPORT_0_IRQ, NULL, NULL, NULL },
	{ pdFALSE, serPORT_1_INT_REG, serPORT_1_BAUD_REG, serPORT_1_RX_REG, serPORT_1_TX_REG, serPORT_1_STATUS_REG, serPORT_1_CTRL_REG, serPORT_1_IRQ, NULL, NULL, NULL }
};

typedef xComPort * xComPortHandle;

/* These prototypes are repeated here so we don't have to include the serial header.  This allows
the xComPortHandle structure details to be private to this file. */
xComPortHandle xSerialPortInit( eCOMPort ePort, eBaud eWantedBaud, eParity eWantedParity, eDataBits eWantedDataBits, eStopBits eWantedStopBits, unsigned portBASE_TYPE uxBufferLength );
portBASE_TYPE xSerialGetChar( xComPortHandle pxPort, portCHAR *pcRxedChar, portTickType xBlockTime );
portBASE_TYPE xSerialPutChar( xComPortHandle pxPort, portCHAR cOutChar, portTickType xBlockTime );
void vSerialClose( xComPortHandle xPort );
portSHORT sSerialWaitForSemaphore( xComPortHandle xPort );
/*-----------------------------------------------------------*/