Resumes pulse capture after an optional trigger pulse.

def resume(self, trigger_duration=0):
        """Resumes pulse capture after an optional trigger pulse."""
        if trigger_duration != 0:
            self._mq.send("t%d" % trigger_duration, True, type=1)
        else:
            self._mq.send("r", True, type=1)
        self._paused = False