help - how do I implement XonXoff Handshaking with MSComm 
Author Message
 help - how do I implement XonXoff Handshaking with MSComm

Hi all,
        I am writing a program to interface with a unit that requires Xon
Xoff handshaking. I know I can set the properties with MSComm but do I need
to do some checking of the Xon signals to prevent sending data to the unit
when it is not ready to accept. If so , how do I do this.
    I have set up a 2nd PC to be the unit. I can send the string to the 2nd
PC but when I try to return a message from the 2nd PC to the 1st PC upon
receipt of the string, I get a randomly truncated reply. Any tips as to what
I am doing wrong.?

Thanks in advance

Paul Flynn

The code is:
Private Sub MSComm1_OnComm()

Dim InBuff As String
   Select Case MSComm1.CommEvent
   'No errors generated

   ' Events
      Case comEvCD   ' Change in the CD line.
      Case comEvCTS   ' Change in the CTS line.
      Case comEvDSR   ' Change in the DSR line.
      Case comEvRing   ' Change in the Ring Indicator.
      Case comEvReceive   ' Received RThreshold # of
                        ' chars.

           InBuff = MSComm1.Input
           Call HandleInput(InBuff)
      Case comEvSend   .

      Case comEvEOF
End Select
End Sub

Sub HandleInput(InBuff As String)
Text3.text = InBuff
End Sub

Tue, 11 May 2004 07:01:12 GMT  
 [ 1 post ] 

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