[RESOLVED] MSComm Serial Receive issue

[passel]

So, the debug print shows you're receiving some number of characters each event, so the full message comes across in 18 or more pieces.
You accumulate these pieces in the textbox, so see the fully assembled message. You need to accumulate these pieces in your string until you have the full message to parse, or you could accumulate lines, and parse as you go, but you may as well just accumulate the full message as your code is basically making the assumption you have the full message when you parse.

You do a println with the last data line followed by a println with an empty string, so there should be two line terminations in a row at the end of your data.
I don't have a serial setup to test, but given your original code, something along the lines of :

Private Sub comRS232_OnComm()
 
 Static vrBuffer As String
 
 Dim lgFwV As Long
 Dim lgFwDate As Long
 Dim lgFwTime As Long
 
 comRS232.InputLen = 0
 
'rem  vrBuffer = ""
  Dim EndOfMsgFlag As String
  EndOfMsgFlag = vbLf & vbLf  'or possibly vbCrLf & vbCrLf depending on what your line terminations are.
  vrBuffer = vrBuffer & comRS232.Input   'Add whatever characters have been received this event to the string

  If InStr(vrBuffer, EndOfMsgFlag) <> 0 Then  'vrBuffer has all the data, including the two line terminations at the end
 
    lgFwV = InStr(vrBuffer, "FWVER=")
 
    lgFwDate = InStr(vrBuffer, "DATE=")
    lgFwTime = InStr(vrBuffer, "TIME=")
 
    If lgFwV > 0 Then
      lblFwVer.Caption = Mid$(vrBuffer, lgFwV + 6, 3)
    End If
 
    If lgFwDate > 0 Then
      lblFwDate.Caption = Mid$(vrBuffer, lgFwDate + 5, 11)
    End If
 
    If lgFwTime > 0 Then
      lblFwTime.Caption = Mid$(vrBuffer, lgFwTime + 5, 8)
    End If
 
    Debug.Print vrBuffer
 
    txtSerial.Text = txtSerial.Text + vrBuffer
    txtSerial.SelStart = Len(txtSerial.Text)

   vrBuffer = ""   'we've parsed the complete message so empty the string to accumulate the next message  
  End If    
End Sub

Note that vrBuffer is declared to be static, so that it will hold its previous contents from one event to the next. If you "Dim" it, it goes away at the end of the sub and is created anew every time the sub is called.