public static int OpenComPort(ref UCView.COMPORTPARAM ComParam)
{
string szPort = "\\\\.\\COM" + (ComParam.nPort + 1);
int hComm = WinApi.CreateFile(szPort, WinApi.GENERIC_READ | WinApi.GENERIC_WRITE, 0, 0, WinApi.OPEN_EXISTING, WinApi.FILE_ATTRIBUTE_NORMAL, 0);
if (WinApi.INVALID_HANDLE_VALUE == hComm)
{
return(WinApi.INVALID_HANDLE_VALUE);
}
//Setup COM port.
WinApi.SetupComm(hComm, COM_BUFF_SIZE, COM_BUFF_SIZE);
byte stopBits = 0;
switch (ComParam.nStopBits)
{
default:
case 1:
stopBits = WinApi.ONESTOPBIT;
break;
case 2:
stopBits = WinApi.TWOSTOPBITS;
break;
}
WinApi.DCB dcb = new WinApi.DCB();
WinApi.GetCommState(hComm, ref dcb);
dcb.BaudRate = (int)ComParam.lBaudRate;
dcb.ByteSize = (byte)ComParam.nDataBits;
dcb.StopBits = (byte)stopBits;
dcb.Parity = (byte)ComParam.nParity;
//0==NOPARITY 1==ODDPARITY 2==EVENPARITY
//3==MARKPARITY 4==SPACEPARITY
if (!WinApi.SetCommState(hComm, ref dcb))
{
WinApi.CloseHandle(hComm);
return(WinApi.INVALID_HANDLE_VALUE);
}
WinApi.SetCommMask(hComm, WinApi.EV_RXFLAG | WinApi.EV_BREAK);
//Setup COM timeout
WinApi.PurgeComm(hComm, WinApi.PURGE_TXABORT | WinApi.PURGE_RXABORT | WinApi.PURGE_TXCLEAR | WinApi.PURGE_RXCLEAR);
//NOTE::dentifies the communications resource. The CreateFile function returns this handle.
// set up for Non_blocking IO.
WinApi.COMMTIMEOUTS CommTimeOuts;
CommTimeOuts.ReadIntervalTimeout = 0xFFFFFFFF;
CommTimeOuts.ReadTotalTimeoutMultiplier = 0;
CommTimeOuts.ReadTotalTimeoutConstant = 0;
// CBR_9600 is approximately 1byte/ms. For our purposes, allow
// double the expected time per character for a fudge factor.
if (dcb.BaudRate > 9600)
{
//2*CBR_9600/BAUDRATE(npTTYInfo);
CommTimeOuts.WriteTotalTimeoutMultiplier = 10;
}
else
{
CommTimeOuts.WriteTotalTimeoutMultiplier = 50;
}
CommTimeOuts.WriteTotalTimeoutConstant = 0;
WinApi.SetCommTimeouts(hComm, ref CommTimeOuts);
return(hComm);
}
public static extern bool SetCommState(int hFile, ref WinApi.DCB lpDCB);
