Public Class Form1
 
    Private Function ByteToHex(ByVal comByte As Byte()) As String
        Dim builder As New StringBuilder(comByte.Length * 3)
        For Each data As Byte In comByte
            builder.Append(Convert.ToString(data, 16).PadLeft(2, "0"c)) _
              '.PadRight(3, " "c))
        Next
 
        Return builder.ToString().ToUpper()
    End Function
 
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As _
      System.EventArgs) Handles Button1.Click
 
        SerialPort1.Open()
 
        Dim bufferSenden() As Byte = {&H1}
        SerialPort1.Write(bufferSenden, 0, bufferSenden.Length)
 
        Dim bytes As Integer = SerialPort1.BytesToRead
        Dim comBuffer As Byte() = New Byte(bytes - 1) {}
        SerialPort1.Read(comBuffer, 0, bytes)
        Threading.Thread.Sleep(60)
        Dim Final As String
        Final = ByteToHex(comBuffer)
        Label1.Text = Final
 
        SerialPort1.Close()
 
    End Sub
End Class