Hi All

This is a direct cut/paste of the code snipet that comes with VB Express edition for serial comms, it doesnt work, it locks the prog up and can only be stopped with ctrl/alt/del.
After some investigation i found that its the RX part thats wrong, the TX part sends the byte "S" out the serial port.
All i want to do is send "S" out the port to my PIC and my PIC sends a string of chars back (which i want to display in a text box) this should not be too hard but im starting to bang my head on the wall, know what i mean ?.
Any help wil be apreciated.

'--------------------------------------------------------------------------

Using comPort As SerialPort = My.Computer.Ports.OpenSerialPort("COM1", 9600)
comPort.DtrEnable = True
comPort.Write("S")

' All data transfer code goes here.

End Using

'All the above works
'------------------------------------------------------------------------
'All below does not work

Dim buffer As New StringBuilder()
Using comPort As SerialPort = My.Computer.Ports.OpenSerialPort("COM1")
Do
Dim line As String = comPort.ReadLine()
If line Is Nothing Then
Exit Do
Else
buffer.AppendLine(line)
End If
Loop
End Using
'--------------------------------------------------------------------------