Baud Rate changing Break Command in vb.net - vb.net

Question

I am using AirCable Serial5 Bluetooth adapter for RS232 to Bluetooth transfer. I need to change Baudrate from lower 9600 to 115200. I talked with AirCable supplier and he said that, for that I have to send Baud changing Break command(0x85) to serial COM port. I don't know how to send break command with baud changing HEX code in VB.NET
Imports System
Imports System.IO.Ports
Imports System.Text
Imports System.Threading
Public Class Form1
Private Sp As New SerialPort
Private comBuffer As Byte()
Private Delegate Sub UpdateFormDelegate()
Private UpdateFormDelegate1 As UpdateFormDelegate
Dim m As Integer
Private Sub Form1_Load(sender As System.Object, e As System.EventArgs) Handles MyBase.Load
With Sp
.PortName = "COM8"
.BaudRate = 9600
.DataBits = 8
.Parity = Parity.None
.StopBits = StopBits.One
.Handshake = Handshake.None
End With
Try
Sp.Open()
Catch ex As Exception
MessageBox.Show(ex.Message)
End Try
AddHandler Sp.DataReceived, AddressOf Sp_DataReceived
Sp.Write("s r0x90 115200" + vbCr)
Thread.Sleep(100)
End Sub
Private Sub Form1_FormClosing(sender As Object, e As System.Windows.Forms.FormClosingEventArgs) Handles Me.FormClosing
Sp.Write("s r0x90 9600" + vbCr)
Thread.Sleep(100)
End Sub
Private Sub getBD_Click(sender As System.Object, e As System.EventArgs) Handles getBD.Click
Sp.Write("g r0x90" + vbCr)
Thread.Sleep(100)
End Sub
Private Sub Sp_DataReceived(ByVal Sender As Object, ByVal e As SerialDataReceivedEventArgs)
'Handles serial port data received events
UpdateFormDelegate1 = New UpdateFormDelegate(AddressOf UpdateDisplay)
Dim n As Integer = Sp.BytesToRead 'find number of bytes in buffer
m = n
comBuffer = New Byte(n - 1) {} 're dimension storage buffer
Sp.Read(comBuffer, 0, n) 'read data from the buffer
Me.Invoke(UpdateFormDelegate1) 'call the delegate
End Sub
Private Sub UpdateDisplay()
' updates label text
'Label1.Text = ""
Dim b As Integer = 0
Do Until b = m
Dim array() As Byte = {CStr(comBuffer(b))}
Dim value As String = System.Text.ASCIIEncoding.ASCII.GetString(array)
Label1.Text += value
b += 1
Loop
End Sub
Private Sub snd_Click(sender As System.Object, e As System.EventArgs) Handles snd.Click
Dim x As String
x = cmdBox.Text
Sp.Write(x + vbCr)
Thread.Sleep(100)
End Sub
End Class
Please let me know if you have any questions.