/// <summary>
/// Opens the com port and configures it with the required settings
/// </summary>
/// <returns>false if the port could not be opened</returns>
protected bool Open
(byte comNum, ushort portSpeed, ushort portParity, ushort portStopBits
)
{
if (online)
{
return(false);
}
string comtxt = "COM" + comNum.ToString();
hPort = RSWrapper.CreateFile
(
comtxt, RSWrapper.GENERIC_READ | RSWrapper.GENERIC_WRITE, 0, IntPtr.Zero, RSWrapper.OPEN_EXISTING,
0, IntPtr.Zero
);
if (hPort == (IntPtr)RSWrapper.INVALID_HANDLE_VALUE)
{
return(false);
}
if (!SetComStat((RSWrapper.BAUD_RATE)portSpeed, (RSWrapper.ParityBit)portParity, (RSWrapper.StopBits)portStopBits, 8))
{
return(false);
}
if (!AfterOpen())
{
Close();
return(false);
}
online = true;
return(true);
}
/// <summary>
/// Sends a protocol byte immediately ahead of any queued bytes.
/// </summary>
/// <param name="tosend">Byte to send</param>
/// <returns>False if an immediate byte is already scheduled and not yet sent</returns>
protected bool SendImmediate(byte tosend)
{
CheckOnline();
if (RSWrapper.TransmitCommChar(hPort, tosend))
{
return(true);
}
return(false);
}
/// <summary>
/// The ReadFile function reads data from a serial port,
/// </summary>
/// <param name="toRead">Pointer to the buffer that receives the data read from</param>
/// <param name="maxDataLength">[in] Number of bytes to be read from the port</param>
/// <param name="dataLength">Variable that receives the number of bytes read. Read sets this value to zero
/// before doing any work or error checking. </param>
/// <returns>If the function succeeds, the return value is true. </returns>
protected bool Read(IntPtr toRead, uint maxDataLength, out uint dataLength)
{
if (RSWrapper.ReadFile(hPort, toRead, maxDataLength, out dataLength, ptrUWO))
{
incBytesTransferred(dataLength);
return(true);
}
else
{
return(false);
}
}
/// <summary>
/// Check if the port is online.
/// </summary>
/// <returns></returns>
protected bool CheckOnline()
{
uint f;
if (online)
{
if (RSWrapper.GetHandleInformation(hPort, out f))
{
return(true);
}
}
return(false);
}//CheckOnline
protected bool Send(Byte[] tosend)
{
uint sent = 0;
ushort writeCount = (ushort)tosend.GetLength(0);
CheckOnline();
if ((RSWrapper.WriteFile(hPort, tosend, writeCount, out sent, ptrUWO)) && (writeCount == sent))
{
incBytesTransferred(writeCount);
return(true);
}
return(false);
}
/// <summary>
/// The GetCommState function retrieves the current control settings for a specified communications device.
/// </summary>
/// <param name="BaudRate">Baud rate at which the communications device operates.</param>
/// <param name="Parity">If param is TRUE, parity checking is performed and errors are reported.</param>
/// <param name="StopBits">Number of stop bits to be used.
/// </param>
/// <param name="ByteSize">Number of bits in the bytes transmitted and received.</param>
/// <returns></returns>
protected bool GetComStatSel
(ref Int32 BaudRate, ref RSWrapper.ParityBit Parity, ref RSWrapper.StopBits StopBits, ref byte ByteSize)
{
RSWrapper.DCB PortDCB = new RSWrapper.DCB();
if (!RSWrapper.GetCommState(hPort, ref PortDCB))
{
return(false);
}
BaudRate = PortDCB.BaudRate;
ByteSize = PortDCB.ByteSize;
Parity = PortDCB.Parity;
StopBits = PortDCB.stopBits;
return(true);
}
/// <summary>
/// Queues bytes for transmission.
/// </summary>
/// <param name="tosend">Array of bytes to be sent</param>
/// <param name="dataLength">the length of data</param>
protected bool Send(IntPtr tosend, ushort dataLength)
{
uint sent = 0;
if (!CheckOnline())
{
return(false);
}
if ((RSWrapper.WriteFile(hPort, tosend, dataLength, out sent, ptrUWO)) && (dataLength == sent))
{
incBytesTransferred(dataLength);
return(true);
}
else
{
return(false);
}
}
/// <summary>
/// This function configures a communications device
/// </summary>
/// <param name="BaudRate">Specifies the baud rate at which the communication device operates.</param>
/// <param name="Parity">Specifies the parity scheme to be used.</param>
/// <param name="StopBits">Specifies the number of stop bits to be used.</param>
/// <param name="ByteSize">Specifies the number of bits in the bytes transmitted and received.</param>
/// <returns>true indicates success.</returns>
protected bool SetComStat
(RSWrapper.BAUD_RATE BaudRate, RSWrapper.ParityBit Parity, RSWrapper.StopBits StopBits, byte ByteSize)
{
RSWrapper.DCB PortDCB = new RSWrapper.DCB();
if (!RSWrapper.GetCommState(hPort, ref PortDCB))
{
return(false);
}
PortDCB.BaudRate = (int)BaudRate;
PortDCB.ByteSize = ByteSize;
PortDCB.Parity = Parity;
PortDCB.stopBits = StopBits;
if (!RSWrapper.SetCommState(hPort, ref PortDCB))
{
return(false);
}
return(true);
}
}//CheckOnline
//The ClearCommError function retrieves information about a communications error and reports the current
// status of a communications device.
/// <summary>
/// The ClearCommError function retrieves information about a communications error and reports the current
/// status of a communications device.
/// </summary>
/// <param name="inRxQueue">Position in rx queue</param>
/// <param name="inTxQueue">Position in tx queue</param>
/// <returns></returns>
protected bool ClearCommErrorSel(out UInt32 inRxQueue, out UInt32 inTxQueue)
{
RSWrapper.COMSTAT cs;
uint er;
inRxQueue = 0;
inTxQueue = 0;
if (!CheckOnline())
{
return(false);
}
if (!RSWrapper.ClearCommError(hPort, out er, out cs))
{
return(false);
}
inRxQueue = cs.cbInQue;
inTxQueue = cs.cbOutQue;
return(true);
}
private void InternalClose()
{
RSWrapper.CloseHandle(hPort);
online = false;
}