Type these variables at the top of your form

Dim in_data As String
Dim sData As Byte
 
Type this instruction in the Form load event

CheckForIllegalCrossThreadCalls=False

Add the following code to your form

Private Sub SerialPort1_DataReceived(ByVal sender As System.Object, ByVal e As System.IO.Ports.SerialDataReceivedEventArgs) Handles SerialPort1.DataReceived
 
         Do
            in_data = SerialPort1.ReadLine()
         Loop Until in_data = "TX"
         
         in_data = SerialPort1.ReadLine()

         TextBox1.Text=in_data

         SerialPort1.ReadExisting()

         SerialPort1.WriteLine("!" & vbLf & sData)

End Sub

Use as many buttons as you like to assign a value to sData, in the Button_Click event type

sData=any value you like between 0 and 255


For the Stamp use this code


dir VAR Byte 
pulseCount VAR Byte
x VAR Byte

x=83

DO

SEROUT 16,16780,["TX",10,DEC x,10]
SERIN 16,16780,15,timeout,[WAIT("!"),DEC3 dir] 
timeout:
IF (dir=1) THEN
FOR pulseCount = 0 TO 50
PULSOUT 13,650
PULSOUT 12,850
NEXT
ENDIF

LOOP
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