This is a pretty common thing to do. You should be able to detect RTS/CTS or DCD assuming as martell said the handshaking signals are supported by Device::SerialPort.

Update1: Looks like both modem control(DCD) and handshaking(RTS/CTS) are both supported.

if ($PortObj->can_wait_modemlines) {
      $rc = $PortObj->wait_modemlines( MS_RLSD_ON );
      if (!$rc) { print "carrier detect changed\n"; }
  }

  if ($PortObj->can_modemlines) {
     $ModemStatus = $PortObj->modemlines;
     if ($ModemStatus & $PortObj->MS_RLSD_ON) { print "carrier detecte
+d\n"; }
  }

[download]
# controlling outputs from the port
  $PortObj->dtr_active(T);              # sends outputs direct to hard
+ware
  $PortObj->rts_active(Yes);            # return status of ioctl call
                                        # return undef on failure

[download]

James

There's never enough time to do it right, but always enough time to do it over...

In reply to Re: Need to detect continuity between 2 terminals by jmlynesjr
in thread Need to detect continuity between 2 terminals by redss

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