boot/freeldr/fdebug/rs232.c

   1 /*
   2  *  FreeLoader - rs232.c
   3  *
   4  *  Copyright (C) 2003  Brian Palmer  <brianp@sginet.com>
   5  *
   6  *  This program is free software; you can redistribute it and/or modify
   7  *  it under the terms of the GNU General Public License as published by
   8  *  the Free Software Foundation; either version 2 of the License, or
   9  *  (at your option) any later version.
  10  *
  11  *  This program is distributed in the hope that it will be useful,
  12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  *  GNU General Public License for more details.
  15  *
  16  *  You should have received a copy of the GNU General Public License along
  17  *  with this program; if not, write to the Free Software Foundation, Inc.,
  18  *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  19  */
  20
  21 #include <windows.h>
  22 #include <winioctl.h>
  23 #include <tchar.h>
  24 #include <stdio.h>
  25
  26 #include "rs232.h"
  27
  28
  29 HANDLE    hPortHandle = NULL;
  30
  31
  32 BOOL Rs232OpenPortWin32(TCHAR* CommPort)
  33 {
  34     TCHAR    PortName[MAX_PATH];
  35     DWORD    ErrorCode;
  36
  37     // First check and make sure they don't already have the
  38     // OBD2 connection open. We don't want to open things twice.
  39     if (hPortHandle != NULL)
  40     {
  41         _tprintf(TEXT("Port handle not NULL. Must be already open. Returning FALSE...\n"));
  42         return FALSE;
  43     }
  44
  45     _stprintf(PortName, TEXT("\\\\.\\%s"), CommPort);
  46
  47     hPortHandle = CreateFile(PortName,
  48                             GENERIC_READ|GENERIC_WRITE,
  49                             0,
  50                             0,
  51                             OPEN_EXISTING,
  52                             0,
  53                             0);
  54
  55     if (hPortHandle == INVALID_HANDLE_VALUE)
  56     {
  57         hPortHandle = NULL;
  58         ErrorCode = GetLastError();
  59
  60         _tprintf(TEXT("CreateFile(\"%s\") failed. GetLastError() = %lu.\n"), PortName, ErrorCode);
  61
  62         return FALSE;
  63     }
  64
  65     return TRUE;
  66 }
  67
  68 BOOL Rs232ClosePortWin32(VOID)
  69 {
  70     HANDLE    hTempPortHandle = hPortHandle;
  71
  72     hPortHandle = NULL;
  73
  74     if (hTempPortHandle == NULL)
  75     {
  76         return FALSE;
  77     }
  78
  79     return CloseHandle(hTempPortHandle);
  80 }
  81
  82 // DeviceControlString
  83 //   [in] Pointer to a null-terminated string that specifies device-control information.
  84 //   The string must have the same form as the mode command's command-line arguments.
  85 //
  86 //   For example, the following string specifies a baud rate of 1200, no parity, 8 data bits, and 1 stop bit:
  87 //   "baud=1200 parity=N data=8 stop=1"
  88 //
  89 //   The following string specifies a baud rate of 115200, no parity, 8 data bits, and 1 stop bit:
  90 //   "115200,n,8,1"
  91 //
  92 //   The device name is ignored if it is included in the string, but it must specify a valid device, as follows:
  93 //   "COM1: baud=1200 parity=N data=8 stop=1"
  94 //
  95 //   For further information on mode command syntax, refer to the end-user documentation for your operating system.
  96 BOOL Rs232ConfigurePortWin32(TCHAR* DeviceControlString)
  97 {
  98     DCB        dcb;
  99     DWORD    ErrorCode;
 100
 101     /*if (!GetCommState(hPortHandle, &dcb))
 102     {
 103         ErrorCode = GetLastError();
 104
 105         _tprintf(TEXT("GetCommState() failed. GetLastError() = %lu.\n"), ErrorCode);
 106
 107         return FALSE;
 108     }
 109
 110     dcb.BaudRate = BaudRate;
 111     dcb.ByteSize = DataBits;
 112     dcb.Parity = Parity;
 113     dcb.StopBits = StopBits;
 114     dcb.fBinary = TRUE;
 115     dcb.fDsrSensitivity = FALSE;
 116     dcb.fParity = (Parity == NOPARITY) ? FALSE : TRUE;
 117     dcb.fOutX = FALSE;
 118     dcb.fInX = FALSE;
 119     dcb.fNull = FALSE;
 120     dcb.fAbortOnError = TRUE;
 121     dcb.fOutxCtsFlow = FALSE;
 122     dcb.fOutxDsrFlow = FALSE;
 123     dcb.fDtrControl = DTR_CONTROL_DISABLE;
 124     dcb.fDsrSensitivity = FALSE;
 125     dcb.fRtsControl = RTS_CONTROL_DISABLE;
 126     dcb.fOutxCtsFlow = FALSE;
 127     dcb.fOutxCtsFlow = FALSE;*/
 128
 129
 130     memset(&dcb, 0, sizeof(DCB));
 131     dcb.DCBlength = sizeof(dcb);
 132     if (!BuildCommDCB(DeviceControlString, &dcb))
 133     {
 134         ErrorCode = GetLastError();
 135
 136         _tprintf(TEXT("BuildCommDCB() failed. GetLastError() = %lu.\n"), ErrorCode);
 137
 138         return FALSE;
 139     }
 140
 141     if (!SetCommState(hPortHandle, &dcb))
 142     {
 143         ErrorCode = GetLastError();
 144
 145         _tprintf(TEXT("SetCommState() failed. GetLastError() = %lu.\n"), ErrorCode);
 146
 147         return FALSE;
 148     }
 149
 150     // Set the timeouts
 151     if (!Rs232SetCommunicationTimeoutsWin32(MAXDWORD, 0, 0, 0, 0))
 152     {
 153         return FALSE;
 154     }
 155
 156     return TRUE;
 157 }
 158
 159 // Members
 160 //  ReadIntervalTimeout
 161 //   Specifies the maximum time, in milliseconds, allowed to elapse between the arrival of two characters on the communications line. During a ReadFile operation, the time period begins when the first character is received. If the interval between the arrival of any two characters exceeds this amount, the ReadFile operation is completed and any buffered data is returned. A value of zero indicates that interval time-outs are not used.
 162 //   A value of MAXDWORD, combined with zero values for both the ReadTotalTimeoutConstant and ReadTotalTimeoutMultiplier members, specifies that the read operation is to return immediately with the characters that have already been received, even if no characters have been received.
 163 //
 164 //  ReadTotalTimeoutMultiplier
 165 //   Specifies the multiplier, in milliseconds, used to calculate the total time-out period for read operations. For each read operation, this value is multiplied by the requested number of bytes to be read.
 166 //  ReadTotalTimeoutConstant
 167 //   Specifies the constant, in milliseconds, used to calculate the total time-out period for read operations. For each read operation, this value is added to the product of the ReadTotalTimeoutMultiplier member and the requested number of bytes.
 168 //   A value of zero for both the ReadTotalTimeoutMultiplier and ReadTotalTimeoutConstant members indicates that total time-outs are not used for read operations.
 169 //
 170 //  WriteTotalTimeoutMultiplier
 171 //   Specifies the multiplier, in milliseconds, used to calculate the total time-out period for write operations. For each write operation, this value is multiplied by the number of bytes to be written.
 172 //  WriteTotalTimeoutConstant
 173 //   Specifies the constant, in milliseconds, used to calculate the total time-out period for write operations. For each write operation, this value is added to the product of the WriteTotalTimeoutMultiplier member and the number of bytes to be written.
 174 //   A value of zero for both the WriteTotalTimeoutMultiplier and WriteTotalTimeoutConstant members indicates that total time-outs are not used for write operations.
 175 //
 176 // Remarks
 177 //  If an application sets ReadIntervalTimeout and ReadTotalTimeoutMultiplier to MAXDWORD and sets ReadTotalTimeoutConstant to a value greater than zero and less than MAXDWORD, one of the following occurs when the ReadFile function is called:
 178 //
 179 //   If there are any characters in the input buffer, ReadFile returns immediately with the characters in the buffer.
 180 //   If there are no characters in the input buffer, ReadFile waits until a character arrives and then returns immediately.
 181 //   If no character arrives within the time specified by ReadTotalTimeoutConstant, ReadFile times out.
 182 BOOL Rs232SetCommunicationTimeoutsWin32(DWORD ReadIntervalTimeout, DWORD ReadTotalTimeoutMultiplier, DWORD ReadTotalTimeoutConstant, DWORD WriteTotalTimeoutMultiplier, DWORD WriteTotalTimeoutConstant)
 183 {
 184     COMMTIMEOUTS    ct;
 185     DWORD            ErrorCode;
 186
 187     if (!GetCommTimeouts(hPortHandle, &ct))
 188     {
 189         ErrorCode = GetLastError();
 190
 191         _tprintf(TEXT("GetCommTimeouts() failed. GetLastError() = %lu.\n"), ErrorCode);
 192
 193         return FALSE;
 194     }
 195
 196     ct.ReadIntervalTimeout = ReadIntervalTimeout;
 197     ct.ReadTotalTimeoutConstant = ReadTotalTimeoutConstant;
 198     ct.ReadTotalTimeoutMultiplier = ReadTotalTimeoutMultiplier;
 199     ct.WriteTotalTimeoutConstant = WriteTotalTimeoutConstant;
 200     ct.WriteTotalTimeoutMultiplier = WriteTotalTimeoutMultiplier;
 201
 202     if (!SetCommTimeouts(hPortHandle, &ct))
 203     {
 204         ErrorCode = GetLastError();
 205
 206         _tprintf(TEXT("SetCommTimeouts() failed. GetLastError() = %lu.\n"), ErrorCode);
 207
 208         return FALSE;
 209     }
 210
 211     return TRUE;
 212 }
 213
 214 BOOL Rs232ReadByteWin32(BYTE* DataByte)
 215 {
 216     DWORD    BytesRead = 0;
 217     DWORD    ErrorCode;
 218
 219     // If ReadFile() fails then report error
 220     if (!ReadFile(hPortHandle, DataByte, 1, &BytesRead, NULL))
 221     {
 222         ErrorCode = GetLastError();
 223
 224         _tprintf(TEXT("ReadFile() failed. GetLastError() = %lu.\n"), ErrorCode);
 225
 226         return FALSE;
 227     }
 228
 229     // If ReadFile() succeeds, but BytesRead isn't 1
 230     // then a timeout occurred.
 231     if (BytesRead != 1)
 232     {
 233         return FALSE;
 234     }
 235
 236     return TRUE;
 237 }
 238
 239 BOOL Rs232WriteByteWin32(BYTE DataByte)
 240 {
 241     DWORD    BytesWritten = 0;
 242     BOOL    Success;
 243     DWORD    ErrorCode;
 244
 245     Success = WriteFile(hPortHandle, &DataByte, 1, &BytesWritten, NULL);
 246
 247     if (!Success || BytesWritten != 1)
 248     {
 249         ErrorCode = GetLastError();
 250
 251         _tprintf(TEXT("WriteFile() failed. GetLastError() = %lu.\n"), ErrorCode);
 252
 253         return FALSE;
 254     }
 255
 256     return TRUE;
 257 }