Populating datagrid from serialport - wpf

Question

I am working on a program that is a decoder, it reads from an interface connected through the serial port and I am then interpreting the information and putting it into a datagrid. I am having a problem where not all of the information is getting transferred into the datagrid, but I'm not sure why.
// Declare a delegate for method DoUpdate().
private delegate void MethodDelegate();
private MethodDelegate ReadSerialData;
bool loggerRunning;
private void button1_Click(object sender, RoutedEventArgs e)
{
if (!loggerRunning)
{
// Delegate for DoUpdate.
ReadSerialData = new MethodDelegate(DoUpdate);
//Create new serialport.
Sp = new SerialPort();
//Set the appropriate properties.
Sp.PortName = SetPortName(Sp.PortName);
Sp.BaudRate = SetBaudRate(Sp.BaudRate);
Sp.Parity = Parity.None;
Sp.DataBits = SetDataBits(Sp.DataBits);
Sp.StopBits = StopBits.One;
Sp.Handshake = Handshake.None;
Sp.DataReceived += new SerialDataReceivedEventHandler(serialPort1_DataReceived);
Sp.Open();
loggerRunning = true;
}
else
{
Sp.Close();
loggerRunning = false;
}
}
private void serialPort1_DataReceived(object sender, SerialDataReceivedEventArgs e)
{
Dispatcher.Invoke(DispatcherPriority.Normal, ReadSerialData);
}
private List<IEBusData> sortedData = new List<IEBusData>();
// Process received data.
// Via delegate ReadSerialData.
private void DoUpdate()
{
string[] tempRow = new string[35];
try
{
do
{
try
{
String Temp = Sp.ReadByte().ToString("X"); // Read from Input Buffer
Byte_Read++;
if ((Temp == "7B") && (Rx_State != HDR0 || Rx_State != Rx_Data))
{
Rx_State = HDR0;
}
switch (Rx_State)
{
case HDR0: // Check for Header byte 0
// Check to see if matches Header0
if (Temp == "7B")
{ Rx_State++; }
break;
case HDR1: // Check for Header byte 1
if (Temp == "7D")
{
Rx_State++;
}
else
{ Rx_State = HDR0; }
break;
case MSTR_ADDR: // Clock in Master Address
MASTER += Temp;
if (MASTER.Length == 3) // Master Address is 3 bytes
{ Rx_State++; }
break;
case SLVE_ADDR: // Clock in Slave Address
SLAVE += Temp;
if (SLAVE.Length == 3) // Slave Address is 3 bytes
{
tempRow[0] = MASTER; // Put Master Address into Grid
tempRow[1] = SLAVE; // Put Slave Address into Grid
Rx_State++; // Move to next Receive State
MASTER = ""; // Reset MASTER
SLAVE = ""; // Reset SLAVE
}
break;
case Rx_Len: // Clock in Message Length
Length = Convert.ToInt16(Temp, 16); // Convert Length back to Hex digit
if (Length <= 0x20)
{
if (Temp.Length == 1)
{
tempRow[2] = "0" + Temp;
}
else
{
tempRow[2] = Temp;
}
Rx_State++;
}
else if (Length == 0x7B)
{ Rx_State = HDR1; }
else if (Length == 0x7D)
{ Rx_State = MSTR_ADDR; }
else
{ Rx_State = HDR0; }
break;
case Rx_Data: // Clock in Data Bytes
if (Temp.Length == 1)
{
tempRow[Data_Column] = "0" + Temp;
}
else
{
tempRow[Data_Column] = Temp;
}
Length--;
Data_Column++;
if (Length < 1) // If all data Received
{
Rx_State = HDR0; // Reset Receive State
Data_Column = 3; // Reset Columns
Curr_Row++; // Increment Row Number
sortedData.Add(new IEBusData(tempRow));
dgIEBus.ItemsSource = sortedData;
dgIEBus.Items.Refresh();
}
break;
default:
break;
}
// this.Update();
}
catch (SystemException)
{ }
} while (Sp.BytesToRead > Byte_Read);
Byte_Read = 0;
}
catch (InvalidOperationException) { }
}
}