export_signals.py 文件源码

def ctr_out_event_pulse_polarity(self):
        """
        :class:`nidaqmx.constants.Polarity`: Specifies the polarity of
            the pulses at the output terminal of the counter when
            **ctr_out_event_output_behavior** is
            **ExportActions2.PULSE**. NI-DAQmx ignores this property if
            **ctr_out_event_output_behavior** is
            **ExportActions2.TOGGLE**.
        """
        val = ctypes.c_int()

        cfunc = lib_importer.windll.DAQmxGetExportedCtrOutEventPulsePolarity
        if cfunc.argtypes is None:
            with cfunc.arglock:
                if cfunc.argtypes is None:
                    cfunc.argtypes = [
                        lib_importer.task_handle, ctypes.POINTER(ctypes.c_int)]

        error_code = cfunc(
            self._handle, ctypes.byref(val))
        check_for_error(error_code)

        return Polarity(val.value)