1 /*

     2 * Copyright (c) 2005-2009 Nokia Corporation and/or its subsidiary(-ies).

     3 * All rights reserved.

     4 * This component and the accompanying materials are made available

     5 * under the terms of "Eclipse Public License v1.0"

     6 * which accompanies this distribution, and is available

     7 * at the URL "http://www.eclipse.org/legal/epl-v10.html".

     8 *

     9 * Initial Contributors:

    10 * Nokia Corporation - initial contribution.

    11 *

    12 * Contributors:

    13 *

    14 * Description:  

    15 * CSerialPort -- encapsulates the details of using the serial port as 

    16 * a communications channel

    17 * System Includes

    18 *

    19 */

    20 

    21 

    22 

    23 #include <stdio.h>

    24 #include <assert.h>

    25 

    26 /*********************************************************************

    27  *

    28  * Local Includes

    29  *

    30  ********************************************************************/

    31 #include "CSerialPort.h"

    32 

    33 /*********************************************************************

    34  *

    35  * Construction

    36  *

    37  ********************************************************************/

    38 CSerialPort::CSerialPort()

    39 {

    40 	iComPort = INVALID_HANDLE_VALUE;

    41 }

    42 

    43 

    44 CSerialPort::~CSerialPort()

    45 {

    46 	assert( iComPort == INVALID_HANDLE_VALUE );

    47 }

    48 

    49 

    50 /*********************************************************************

    51  *

    52  * OpenComPort() -- open a com port, set the timeouts, set the config

    53  *

    54  ********************************************************************/

    55 int CSerialPort::OpenPort( char *aComPort )

    56 {

    57 	int err;

    58 

    59 	// Open the COM Port

    60 	iComPort = CreateFile( aComPort, GENERIC_READ | GENERIC_WRITE, 0, NULL, OPEN_EXISTING, FILE_FLAG_WRITE_THROUGH, NULL );

    61 	if( iComPort == INVALID_HANDLE_VALUE ) {

    62 		err = GetLastError();

    63 		return err;

    64 	}

    65 

    66 	// Set the timeouts

    67 	COMMTIMEOUTS CommTimeOuts;

    68 	CommTimeOuts.ReadIntervalTimeout = 0;

    69 	CommTimeOuts.ReadTotalTimeoutMultiplier = 0;

    70     CommTimeOuts.ReadTotalTimeoutConstant = 0;

    71 	CommTimeOuts.WriteTotalTimeoutMultiplier = 0;

    72 	CommTimeOuts.WriteTotalTimeoutConstant = 0;

    73 	err = SetCommTimeouts( iComPort, &CommTimeOuts );

    74 	if( err == 0 ) {

    75 		err = GetLastError();

    76 		CloseHandle( iComPort );

    77 		iComPort = INVALID_HANDLE_VALUE;

    78 		return err;

    79 	}

    80 

    81 	// Configure the COM port 

    82 	DCB dcb;

    83 	GetCommState(iComPort, &dcb);

    84 	dcb.DCBlength			= sizeof(dcb); 

    85 	dcb.BaudRate			= CBR_115200;

    86 	dcb.fBinary				= TRUE;

    87 	dcb.fParity				= NOPARITY;

    88 	dcb.fOutxCtsFlow		= TRUE;

    89 	dcb.fOutxDsrFlow		= FALSE;

    90 	dcb.fDtrControl			= DTR_CONTROL_ENABLE;	

    91 	dcb.fDsrSensitivity		= FALSE;

    92 	dcb.fTXContinueOnXoff	= TRUE;

    93 	dcb.fOutX				= FALSE;

    94 	dcb.fInX				= FALSE;

    95 	dcb.fErrorChar			= FALSE;

    96 	dcb.fNull				= FALSE;

    97 	dcb.fRtsControl			= RTS_CONTROL_HANDSHAKE;

    98 	dcb.fAbortOnError		= TRUE;

    99 	dcb.XonLim				= 100;

   100 	dcb.XoffLim				= 100;

   101 	dcb.ByteSize			= 8;

   102 	dcb.Parity				= NOPARITY;

   103 	dcb.StopBits			= ONESTOPBIT;

   104 	dcb.XonChar				= 17;

   105 	dcb.XoffChar			= 19;

   106 	err = SetCommState( iComPort, &dcb );	

   107 	if( err == 0 ) {

   108 		err = GetLastError();

   109 		CloseHandle( iComPort );

   110 		iComPort = INVALID_HANDLE_VALUE;

   111 		return err;

   112 	}

   113 

   114 	// Success

   115 	return 0;

   116 }

   117 

   118 

   119 /*********************************************************************

   120  *

   121  * CloseComPort() -- close an open com port.

   122  *

   123  ********************************************************************/

   124 void CSerialPort::ClosePort()

   125 {

   126 	// if the port isn't open then just return

   127 	if( iComPort == INVALID_HANDLE_VALUE ) 

   128 		return;

   129 	

   130 	// close the port

   131 	CloseHandle( iComPort );

   132 	iComPort = INVALID_HANDLE_VALUE;

   133 }

   134 

   135 

   136 /*********************************************************************

   137  *

   138  *  ReceiveBytes() -- read specified number of bytes from the comport

   139  *

   140  ********************************************************************/

   141 int CSerialPort::ReceiveBytes( char* aBuff, int *aSize)

   142 {

   143 	int err;

   144 	int original_size;

   145 	unsigned long iBytesRead;

   146 

   147 	// check the state and the params

   148 	assert( iComPort != INVALID_HANDLE_VALUE );

   149 	assert( aBuff != NULL );

   150 	assert( aSize != NULL );

   151 

   152 	// receive bytes

   153 	original_size = *aSize;

   154 	err = ReadFile( iComPort, aBuff, *aSize, &iBytesRead, NULL );

   155 

   156 	// set aSize to the number actually read

   157 	*aSize = iBytesRead;

   158 

   159 	// check for errors

   160 	if( err == 0 )  {

   161 		err = GetLastError();

   162 		return err;

   163 	}

   164 		

   165 	// this condition should have generated an error -- lets make sure

   166 	assert( *aSize == original_size );

   167 	return 0;

   168 }

   169 

   170 

   171 /*********************************************************************

   172  *

   173  *  SendBytes() -- write the specified number of bytes to the COMport

   174  *

   175  ********************************************************************/

   176 int CSerialPort::SendBytes( char *aBuff, int *aSize )

   177 {

   178 	int ret;

   179 	DWORD dwModemStatus, dwBytes = 0;

   180 

   181 	// check state and params

   182 	assert( iComPort != INVALID_HANDLE_VALUE );

   183 	assert( aBuff != NULL );

   184 	assert( aSize != NULL );

   185 

   186 	// write bytes to the port

   187 	ret = GetCommModemStatus( iComPort, &dwModemStatus );

   188 	ret = WriteFile( iComPort, (LPVOID)aBuff, *aSize, &dwBytes, NULL );

   189 

   190 	// set aSize to the number actually written

   191 	*aSize = dwBytes;

   192 

   193 	// check for errors

   194 	if( ret == 0 ) {

   195 		ret = GetLastError();

   196 		return ret;

   197 	}

   198 	

   199 	// done	

   200 	return 0;	

   201 }