Your recollection on the MSComm being limited is wrong. I have used it various times to support the use of the Comm port handshake lines. The interface into VB gives full support for simple methods to turn the output control lines (RTS and DTR) on and off....as simple as:

' This function sets the state of the comm port DTR line true or
' false according to the entry argument. A TRUE state sets the
' line on the RS232 interface to a +V level while a FALSE puts
' the line to the -V level.

Sub Comm_DTR(DTR_State As Boolean)

  MSComm.DTREnable = DTR_State

End Sub

When using the input handshake lines there are even nice ways to detect the handshake transition events (on CTS and DSR for example) as simple as:

Dim CTS_Flag0 As Integer            ' flags showing foot switch was pressed
Dim CTS_Flag1 As Integer

' this subroutine receives control when there is an event on the
' MS Comm control. This specifically deals with the CTS input which
' activates when the test box foot switch is activated. This response
' routine will set a global variable flag indicating that the CTS was
' detected pressed. A subsequent timer event will note if the flag is
' set is the CTS still in the same state. If so the CTS is deemed to be
' "debounced" and logic from the timer routine will launch the equivalent
' of the "NEXT" key for the calibrate screen.

Private Sub MSComm_OnComm()

  Select Case MSComm.CommEvent

    Case comEvCTS   ' Change in the CTS line.

      If MSComm.CTSHolding = False Then
         CTS_Flag0 = 1           ' foot switch seen pressed
      Else
         CTS_Flag0 = 0           ' foot switch not seen pressed
         CTS_Flag1 = 0           ' so clear both of the flags
      End If
      
  End Select

End Sub

' timer response routine that supports the "debounce" of the
' foot switch input on the CTS line. The first notification of
' the foot switch comes from the MSComm event processing routine.

Private Sub Comm_Timer_Timer()

  ' check if to see a "debounced" foot switch has been detected.
  If CTS_Flag0 <> 0 Then
    
    If CTS_Flag1 <> 0 Then
    
      ' If the Learn Control Button is enabled the invoke its
      ' click via the foot switch from CTS!!
      If MainForm.LearnCtl.Enabled = True Then
        Call MainForm.LearnCtl_Click
      End If
      
      CTS_Flag0 = 0
      CTS_Flag1 = 0
    End If

    If MSComm.CTSHolding = False Then
      CTS_Flag1 = 1
    End If
    
  End If
  
End Sub

Michael Karas