I'm facing problems with reading data from serial port.
Im sending out a command to the spectrum analyzer, and start reading. characters appears continously but i still cant read as its in ascii.
this is what i wrote:



Private Sub Button8_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button8.Click

SerialPort1.WriteLine(Chr(82) & Chr(51) & Chr(13) & vbCrLf)

End Sub


Private Sub DataReceived( _
ByVal sender As Object, _
ByVal e As System.IO.Ports.SerialDataReceivedEventArgs) _
Handles SerialPort1.DataReceived

TextBox3.Invoke(New _
myDelegate(AddressOf updateTextBox3), _
New Object() {})
End Sub

Public Delegate Sub myDelegate()

Public Sub updateTextBox3()
With TextBox3
.Font = New Font("Garamond", 12.0!, FontStyle.Bold)
.AppendText(SerialPort1.ReadExisting & vbCrLf)
.ScrollToCaret()
End With
End Sub

here're my questions:
1)how to convert my data read from port which is in ascii into decimal?
2)the incoming data is running such as in an overflow state,
like,
43
44
43
..
..
..
it goes on...

but i want it to appears as a continuously changing figure.
like XX.XX (keeps changing)

How to write this command?

3) How to write the data read from the serial port into a txt file inside certain folder?