Harry,

My previous post had some errata in the HangUp() function. Below is the corrected version

FUNCTION HangUp
  
    DECLARE INTEGER CloseHandle IN Win32API;
      INTEGER hObject
  
    LOCAL lccmnd, lnresult, lnport, lnwritten
    STORE 0 TO lnresult, lnwritten
    lnport = This.nPort
    lccmnd = 'ATH0' + CF_TEXT
    lnresult = WriteFile(lnport, @lccmnd, LEN(lccmnd), @lnwritten, 0)
    IF lnresult # 0
      = FlushFileBuffers(lnport)
       * Close up
      = CloseHandle(lnport)
    ELSE
      lnresult = GetLastError()
    ENDIF
    RETURN lnresult
  ENDFUNC

The error is in red, Sorry.