$AppMainBoard_Port = Win32::SerialPort->start ($app_cfgfile)
@result=$AppMainBoard_Port->lookclear;
print "Result: @result\n";
@result=$AppMainBoard_Port->purge_all;
print "Result: @result\n";
for ($i=0 ;; ) {
  if ( $c = $AppMainBoard_Port -> input) {
    print "$c";
    do_other-stuff;
  }
}