//
// Com port received data event handler. Called by the operating system when
// there is data available in the rx buffer.
private void COMPortDataReceived(object sender, SerialDataReceivedEventArgs e)
{
byte[] rawData = new byte[84];
byte[] Magic = new byte[4] {
0, 0, 0, 0
};
int MagicCount = 0;
int currentMillisecond;
int Index = 0;
bool bValidData = false;
byte rxChar;
//TODO : FIX TO UTILIZE MAGIC PACKET ON ROLLING BUFFER
rawData = new byte[84];
DataStreamSize = _COMPort.BytesToRead;
//
// Search for the magic packet.
while (_COMPort.BytesToRead > 0)
{
rxChar = Convert.ToByte(_COMPort.ReadByte());
if (Index >= 84)
{
Index = 0;
}
if (bValidData)
{
//
// Read the data from the incoming buffer.
rawData[Index++] = rxChar;
if (((rawData[3] == Convert.ToByte('D')) || (rawData[3] == Convert.ToByte('F'))) && (Index >= 84))
{
//
// Packet received! Get the current time.
Millisecond = DateTime.Now;
currentMillisecond = Millisecond.Millisecond;
DeltaT = currentMillisecond - PreviousMillisecond;
if (DeltaT < 0)
{
DeltaT = DeltaT + 1000;
}
PreviousMillisecond = currentMillisecond;
InputData.Bytes = rawData;
Dispatcher?.Invoke(() => UpdateGUI());
//
// Log all the received data to a log file.
if (LogData)
{
_logWriter.LogWrite(InputData.CSVData);
}
break;
}
}
else
{
Magic[Index] = rxChar;
Index = (Index + 1) % 4;
if (MagicCount >= 3)
{
if (Magic[Index % 4] == 0xFF && Magic[(Index + 1) % 4] == 0xFF && Magic[(Index + 2) % 4] == 0xFF &&
(Magic[(Index + 3) % 4] == Convert.ToByte('D') || Magic[(Index + 3) % 4] == Convert.ToByte('F')))
{
rawData[3] = Magic[(Index + 3) % 4];
Index = 4;
bValidData = true;
MagicCount = 0;
}
}
else
{
MagicCount++;
}
}
}
}