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1 /* |
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2 * Copyright (c) 2005-2009 Nokia Corporation and/or its subsidiary(-ies). |
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3 * All rights reserved. |
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4 * This component and the accompanying materials are made available |
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5 * under the terms of "Eclipse Public License v1.0" |
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6 * which accompanies this distribution, and is available |
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7 * at the URL "http://www.eclipse.org/legal/epl-v10.html". |
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8 * |
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9 * Initial Contributors: |
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10 * Nokia Corporation - initial contribution. |
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11 * |
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12 * Contributors: |
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13 * |
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14 * Description: |
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15 * CSerialPort -- encapsulates the details of using the serial port as |
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16 * a communications channel |
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17 * System Includes |
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18 * |
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19 */ |
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20 |
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21 |
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22 |
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23 #include <stdio.h> |
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24 #include <assert.h> |
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25 |
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26 /********************************************************************* |
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27 * |
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28 * Local Includes |
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29 * |
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30 ********************************************************************/ |
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31 #include "CSerialPort.h" |
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32 |
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33 |
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34 /********************************************************************* |
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35 * |
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36 * Definitions |
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37 * |
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38 ********************************************************************/ |
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39 #define READ_TIMEOUT (1000) |
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40 |
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41 |
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42 /********************************************************************* |
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43 * |
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44 * Construction |
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45 * |
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46 ********************************************************************/ |
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47 CSerialPort::CSerialPort() |
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48 { |
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49 iComPort = INVALID_HANDLE_VALUE; |
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50 iMutex = CreateMutex( NULL, false, NULL ); |
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51 assert (iMutex != NULL); |
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52 } |
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53 |
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54 |
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55 CSerialPort::~CSerialPort() |
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56 { |
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57 assert( iComPort == INVALID_HANDLE_VALUE ); |
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58 CloseHandle( iMutex ); |
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59 iMutex = NULL; |
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60 } |
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61 |
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62 |
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63 /********************************************************************* |
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64 * |
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65 * OpenComPort() -- open a com port, set the timeouts, set the config |
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66 * |
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67 ********************************************************************/ |
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68 int CSerialPort::OpenPort( char *aComPort ) |
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69 { |
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70 int err; |
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71 |
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72 // Open the COM Port |
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73 iComPort = CreateFile( aComPort, GENERIC_READ | GENERIC_WRITE, 0, NULL, OPEN_EXISTING, FILE_FLAG_WRITE_THROUGH, NULL ); |
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74 if( iComPort == INVALID_HANDLE_VALUE ) { |
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75 err = GetLastError(); |
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76 return err; |
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77 } |
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78 |
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79 // Set the timeouts (see msdn for the meaning of these carefully chosen values) |
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80 COMMTIMEOUTS CommTimeOuts; |
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81 CommTimeOuts.ReadIntervalTimeout = MAXDWORD; |
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82 CommTimeOuts.ReadTotalTimeoutMultiplier = MAXDWORD; |
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83 CommTimeOuts.ReadTotalTimeoutConstant = READ_TIMEOUT; |
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84 CommTimeOuts.WriteTotalTimeoutMultiplier = 0; |
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85 CommTimeOuts.WriteTotalTimeoutConstant = 0; |
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86 err = SetCommTimeouts( iComPort, &CommTimeOuts ); |
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87 if( err == 0 ) { |
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88 err = GetLastError(); |
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89 CloseHandle( iComPort ); |
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90 iComPort = INVALID_HANDLE_VALUE; |
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91 return err; |
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92 } |
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93 |
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94 // Configure the COM port - NO FLOW CONTROL |
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95 DCB dcb; |
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96 GetCommState(iComPort, &dcb); |
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97 dcb.DCBlength = sizeof(dcb); |
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98 dcb.BaudRate = CBR_115200; |
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99 // dcb.fBinary = TRUE; |
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100 dcb.fBinary = FALSE; |
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101 dcb.fParity = NOPARITY; |
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102 dcb.fOutxCtsFlow = TRUE; |
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103 dcb.fOutxDsrFlow = FALSE; |
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104 dcb.fDtrControl = DTR_CONTROL_ENABLE; |
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105 dcb.fDsrSensitivity = FALSE; |
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106 dcb.fTXContinueOnXoff = TRUE; |
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107 dcb.fOutX = FALSE; |
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108 dcb.fInX = FALSE; |
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109 dcb.fErrorChar = FALSE; |
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110 dcb.fNull = FALSE; |
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111 // dcb.fRtsControl = RTS_CONTROL_HANDSHAKE; |
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112 dcb.fRtsControl = RTS_CONTROL_ENABLE; |
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113 dcb.fAbortOnError = TRUE; |
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114 dcb.XonLim = 100; |
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115 dcb.XoffLim = 100; |
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116 dcb.ByteSize = 8; |
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117 dcb.Parity = NOPARITY; |
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118 dcb.StopBits = ONESTOPBIT; |
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119 dcb.XonChar = 17; |
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120 dcb.XoffChar = 19; |
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121 err = SetCommState( iComPort, &dcb ); |
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122 if( err == 0 ) { |
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123 err = GetLastError(); |
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124 CloseHandle( iComPort ); |
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125 iComPort = INVALID_HANDLE_VALUE; |
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126 return err; |
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127 } |
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128 |
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129 // raise RTS and DTR so the other end won't block (it can use whatever hw flow control it wants) |
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130 err = EscapeCommFunction( iComPort, SETDTR ); |
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131 assert( err != 0 ); |
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132 err = EscapeCommFunction( iComPort, SETRTS ); |
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133 assert( err != 0 ); |
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134 |
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135 // Success |
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136 return 0; |
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137 } |
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138 |
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139 |
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140 /********************************************************************* |
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141 * |
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142 * CloseComPort() -- close an open com port. |
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143 * |
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144 ********************************************************************/ |
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145 void CSerialPort::ClosePort() |
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146 { |
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147 // if the port isn't open then just return |
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148 if( iComPort == INVALID_HANDLE_VALUE ) |
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149 return; |
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150 |
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151 // close the port |
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152 CloseHandle( iComPort ); |
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153 iComPort = INVALID_HANDLE_VALUE; |
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154 } |
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155 |
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156 |
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157 /********************************************************************* |
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158 * |
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159 * ReceiveBytes() -- read specified number of bytes from the comport |
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160 * |
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161 ********************************************************************/ |
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162 int CSerialPort::ReceiveBytes( char* aBuff, int *aSize ) |
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163 { |
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164 int err, mutex_err; |
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165 int original_size; |
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166 unsigned long iBytesRead; |
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167 |
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168 // check the state and the params |
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169 assert( iComPort != INVALID_HANDLE_VALUE ); |
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170 assert( aBuff != NULL ); |
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171 assert( aSize != NULL ); |
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172 |
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173 // acquire the port mutex |
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174 mutex_err = WaitForSingleObject( iMutex, INFINITE ); |
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175 assert( mutex_err == WAIT_OBJECT_0 ); |
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176 |
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177 // receive bytes |
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178 original_size = *aSize; |
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179 err = ReadFile( iComPort, aBuff, *aSize, &iBytesRead, NULL ); |
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180 |
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181 // give the mutex back |
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182 mutex_err = ReleaseMutex( iMutex ); |
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183 assert( mutex_err != 0 ); |
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184 |
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185 // set aSize to the number actually read |
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186 *aSize = iBytesRead; |
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187 |
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188 // check for errors |
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189 if( err == 0 ) { |
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190 err = GetLastError(); |
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191 return err; |
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192 } |
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193 |
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194 // done |
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195 return 0; |
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196 } |
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197 |
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198 |
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199 /********************************************************************* |
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200 * |
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201 * SendBytes() -- write the specified number of bytes to the COMport |
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202 * |
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203 ********************************************************************/ |
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204 int CSerialPort::SendBytes( char *aBuff, int *aSize ) |
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205 { |
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206 int err, mutex_err; |
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207 DWORD dwModemStatus, dwBytes = 0; |
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208 |
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209 // check state and params |
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210 assert( iComPort != INVALID_HANDLE_VALUE ); |
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211 assert( aBuff != NULL ); |
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212 assert( aSize != NULL ); |
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213 |
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214 // acquire the port mutex |
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215 mutex_err = WaitForSingleObject(iMutex, INFINITE); |
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216 assert( mutex_err == WAIT_OBJECT_0 ); |
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217 |
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218 // write bytes to the port |
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219 err = GetCommModemStatus( iComPort, &dwModemStatus ); |
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220 err = WriteFile( iComPort, (LPVOID)aBuff, *aSize, &dwBytes, NULL ); |
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221 |
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222 // give the mutex back |
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223 mutex_err = ReleaseMutex( iMutex ); |
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224 assert( mutex_err != 0 ); |
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225 |
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226 // set aSize to the number actually written |
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227 *aSize = dwBytes; |
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228 |
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229 // check for errors |
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230 if( err == 0 ) { |
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231 err = GetLastError(); |
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232 return err; |
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233 } |
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234 |
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235 // done |
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236 return 0; |
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237 } |