Python ctypes 模块，c_uint() 实例源码

def _read_ctr_ticks(
        task_handle, high_tick, low_tick, num_samps_per_chan, timeout,
        interleaved=FillMode.GROUP_BY_CHANNEL):
    samps_per_chan_read = ctypes.c_int()

    cfunc = lib_importer.windll.DAQmxReadCtrTicks
    if cfunc.argtypes is None:
        with cfunc.arglock:
            if cfunc.argtypes is None:
                cfunc.argtypes = [
                    lib_importer.task_handle, ctypes.c_int, ctypes.c_double,
                    ctypes.c_int,
                    wrapped_ndpointer(dtype=numpy.uint32, flags=('C', 'W')),
                    wrapped_ndpointer(dtype=numpy.uint32, flags=('C', 'W')),
                    ctypes.c_uint, ctypes.POINTER(ctypes.c_int),
                    ctypes.POINTER(c_bool32)]

    error_code = cfunc(
        task_handle, num_samps_per_chan, timeout, interleaved.value,
        high_tick, low_tick, numpy.prod(high_tick.shape),
        ctypes.byref(samps_per_chan_read), None)
    check_for_error(error_code)

    return samps_per_chan_read.value

def _parse_typedefs(self):
        """
        Determines the ctypes data types of the Task and Cal handles 
        based on the version of the NI-DAQmx driver installed.
        """
        from nidaqmx.system.system import System
        system = System.local()

        # If DAQmx 8.8 and lower, TaskHandle is a typedef for uInt32 since
        # DAQmx didn't support 64-bit applications then.
        version = system.driver_version
        if version.major_version <= 8 and version.minor_version <= 8:
            self._task_handle = ctypes.c_uint
        else:
            self._task_handle = ctypes.c_void_p

        self._cal_handle = ctypes.c_uint

def _major_version(self):
        """
        int: Indicates the major portion of the installed version of NI-
            DAQmx, such as 7 for version 7.0.
        """
        val = ctypes.c_uint()

        cfunc = lib_importer.windll.DAQmxGetSysNIDAQMajorVersion
        if cfunc.argtypes is None:
            with cfunc.arglock:
                if cfunc.argtypes is None:
                    cfunc.argtypes = [
                        ctypes.POINTER(ctypes.c_uint)]

        error_code = cfunc(
            ctypes.byref(val))
        check_for_error(error_code)

        return val.value

def _update_version(self):
        """
        int: Indicates the update portion of the installed version of
            NI-DAQmx, such as 1 for version 9.0.1.
        """
        val = ctypes.c_uint()

        cfunc = lib_importer.windll.DAQmxGetSysNIDAQUpdateVersion
        if cfunc.argtypes is None:
            with cfunc.arglock:
                if cfunc.argtypes is None:
                    cfunc.argtypes = [
                        ctypes.POINTER(ctypes.c_uint)]

        error_code = cfunc(
            ctypes.byref(val))
        check_for_error(error_code)

        return val.value

def di_port_width(self):
        """
        int: Indicates in bits the width of digital input port.
        """
        val = ctypes.c_uint()

        cfunc = lib_importer.windll.DAQmxGetPhysicalChanDIPortWidth
        if cfunc.argtypes is None:
            with cfunc.arglock:
                if cfunc.argtypes is None:
                    cfunc.argtypes = [
                        ctypes_byte_str, ctypes.POINTER(ctypes.c_uint)]

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

        return val.value

def do_port_width(self):
        """
        int: Indicates in bits the width of digital output port.
        """
        val = ctypes.c_uint()

        cfunc = lib_importer.windll.DAQmxGetPhysicalChanDOPortWidth
        if cfunc.argtypes is None:
            with cfunc.arglock:
                if cfunc.argtypes is None:
                    cfunc.argtypes = [
                        ctypes_byte_str, ctypes.POINTER(ctypes.c_uint)]

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

        return val.value

def teds_mfg_id(self):
        """
        int: Indicates the manufacturer ID of the sensor.
        """
        val = ctypes.c_uint()

        cfunc = lib_importer.windll.DAQmxGetPhysicalChanTEDSMfgID
        if cfunc.argtypes is None:
            with cfunc.arglock:
                if cfunc.argtypes is None:
                    cfunc.argtypes = [
                        ctypes_byte_str, ctypes.POINTER(ctypes.c_uint)]

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

        return val.value

def teds_model_num(self):
        """
        int: Indicates the model number of the sensor.
        """
        val = ctypes.c_uint()

        cfunc = lib_importer.windll.DAQmxGetPhysicalChanTEDSModelNum
        if cfunc.argtypes is None:
            with cfunc.arglock:
                if cfunc.argtypes is None:
                    cfunc.argtypes = [
                        ctypes_byte_str, ctypes.POINTER(ctypes.c_uint)]

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

        return val.value

def teds_serial_num(self):
        """
        int: Indicates the serial number of the sensor.
        """
        val = ctypes.c_uint()

        cfunc = lib_importer.windll.DAQmxGetPhysicalChanTEDSSerialNum
        if cfunc.argtypes is None:
            with cfunc.arglock:
                if cfunc.argtypes is None:
                    cfunc.argtypes = [
                        ctypes_byte_str, ctypes.POINTER(ctypes.c_uint)]

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

        return val.value

def teds_version_num(self):
        """
        int: Indicates the version number of the sensor.
        """
        val = ctypes.c_uint()

        cfunc = lib_importer.windll.DAQmxGetPhysicalChanTEDSVersionNum
        if cfunc.argtypes is None:
            with cfunc.arglock:
                if cfunc.argtypes is None:
                    cfunc.argtypes = [
                        ctypes_byte_str, ctypes.POINTER(ctypes.c_uint)]

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

        return val.value

def ai_lowpass_cutoff_freq_range_vals(self):
        """
        List[float]: Indicates pairs of lowpass cutoff frequency ranges
            supported by this device. Each pair consists of the low
            value, followed by the high value. If the device supports a
            set of discrete lowpass cutoff frequencies, use
            **ai_lowpass_cutoff_freq_discrete_vals** to determine the
            supported  frequencies.
        """
        cfunc = lib_importer.windll.DAQmxGetDevAILowpassCutoffFreqRangeVals
        if cfunc.argtypes is None:
            with cfunc.arglock:
                if cfunc.argtypes is None:
                    cfunc.argtypes = [
                        ctypes_byte_str,
                        wrapped_ndpointer(dtype=numpy.float64,
                        flags=('C','W')), ctypes.c_uint]

        temp_size = 0
        while True:
            val = numpy.zeros(temp_size, dtype=numpy.float64)

            size_or_code = cfunc(
                self._name, val, temp_size)

            if is_array_buffer_too_small(size_or_code):
                # Buffer size must have changed between calls; check again.
                temp_size = 0
            elif size_or_code > 0 and temp_size == 0:
                # Buffer size obtained, use to retrieve data.
                temp_size = size_or_code
            else:
                break

        check_for_error(size_or_code)

        return val.tolist()

def carrier_serial_num(self):
        """
        int: Indicates the serial number of the device carrier. This
            value is zero if the carrier does not have a serial number.
        """
        val = ctypes.c_uint()

        cfunc = lib_importer.windll.DAQmxGetCarrierSerialNum
        if cfunc.argtypes is None:
            with cfunc.arglock:
                if cfunc.argtypes is None:
                    cfunc.argtypes = [
                        ctypes_byte_str, ctypes.POINTER(ctypes.c_uint)]

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

        return val.value

def ci_max_size(self):
        """
        int: Indicates in bits the size of the counters on the device.
        """
        val = ctypes.c_uint()

        cfunc = lib_importer.windll.DAQmxGetDevCIMaxSize
        if cfunc.argtypes is None:
            with cfunc.arglock:
                if cfunc.argtypes is None:
                    cfunc.argtypes = [
                        ctypes_byte_str, ctypes.POINTER(ctypes.c_uint)]

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

        return val.value

def co_max_size(self):
        """
        int: Indicates in bits the size of the counters on the device.
        """
        val = ctypes.c_uint()

        cfunc = lib_importer.windll.DAQmxGetDevCOMaxSize
        if cfunc.argtypes is None:
            with cfunc.arglock:
                if cfunc.argtypes is None:
                    cfunc.argtypes = [
                        ctypes_byte_str, ctypes.POINTER(ctypes.c_uint)]

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

        return val.value

def dev_serial_num(self):
        """
        int: Indicates the serial number of the device. This value is
            zero if the device does not have a serial number.
        """
        val = ctypes.c_uint()

        cfunc = lib_importer.windll.DAQmxGetDevSerialNum
        if cfunc.argtypes is None:
            with cfunc.arglock:
                if cfunc.argtypes is None:
                    cfunc.argtypes = [
                        ctypes_byte_str, ctypes.POINTER(ctypes.c_uint)]

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

        return val.value

def num_dma_chans(self):
        """
        int: Indicates the number of DMA channels on the device.
        """
        val = ctypes.c_uint()

        cfunc = lib_importer.windll.DAQmxGetDevNumDMAChans
        if cfunc.argtypes is None:
            with cfunc.arglock:
                if cfunc.argtypes is None:
                    cfunc.argtypes = [
                        ctypes_byte_str, ctypes.POINTER(ctypes.c_uint)]

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

        return val.value

def pci_bus_num(self):
        """
        int: Indicates the PCI bus number of the device.
        """
        val = ctypes.c_uint()

        cfunc = lib_importer.windll.DAQmxGetDevPCIBusNum
        if cfunc.argtypes is None:
            with cfunc.arglock:
                if cfunc.argtypes is None:
                    cfunc.argtypes = [
                        ctypes_byte_str, ctypes.POINTER(ctypes.c_uint)]

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

        return val.value

def pci_dev_num(self):
        """
        int: Indicates the PCI slot number of the device.
        """
        val = ctypes.c_uint()

        cfunc = lib_importer.windll.DAQmxGetDevPCIDevNum
        if cfunc.argtypes is None:
            with cfunc.arglock:
                if cfunc.argtypes is None:
                    cfunc.argtypes = [
                        ctypes_byte_str, ctypes.POINTER(ctypes.c_uint)]

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

        return val.value

def product_num(self):
        """
        int: Indicates the unique hardware identification number for the
            device.
        """
        val = ctypes.c_uint()

        cfunc = lib_importer.windll.DAQmxGetDevProductNum
        if cfunc.argtypes is None:
            with cfunc.arglock:
                if cfunc.argtypes is None:
                    cfunc.argtypes = [
                        ctypes_byte_str, ctypes.POINTER(ctypes.c_uint)]

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

        return val.value

def pxi_chassis_num(self):
        """
        int: Indicates the PXI chassis number of the device, as
            identified in MAX.
        """
        val = ctypes.c_uint()

        cfunc = lib_importer.windll.DAQmxGetDevPXIChassisNum
        if cfunc.argtypes is None:
            with cfunc.arglock:
                if cfunc.argtypes is None:
                    cfunc.argtypes = [
                        ctypes_byte_str, ctypes.POINTER(ctypes.c_uint)]

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

        return val.value

def pxi_slot_num(self):
        """
        int: Indicates the PXI slot number of the device.
        """
        val = ctypes.c_uint()

        cfunc = lib_importer.windll.DAQmxGetDevPXISlotNum
        if cfunc.argtypes is None:
            with cfunc.arglock:
                if cfunc.argtypes is None:
                    cfunc.argtypes = [
                        ctypes_byte_str, ctypes.POINTER(ctypes.c_uint)]

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

        return val.value

def number_of_channels(self):
        """
        int: Indicates the number of virtual channels in the task.
        """
        val = ctypes.c_uint()

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

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

        return val.value

def number_of_devices(self):
        """
        int: Indicates the number of devices in the task.
        """
        val = ctypes.c_uint()

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

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

        return val.value

def pretrig_samples(self):
        """
        int: Specifies the minimum number of pretrigger samples to
            acquire from each channel before recognizing the reference
            trigger. Post-trigger samples per channel are equal to
            **samp_quant_samp_per_chan** minus the number of pretrigger
            samples per channel.
        """
        val = ctypes.c_uint()

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

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

        return val.value

def rdy_for_xfer_event_deassert_cond_custom_threshold(self):
        """
        int: Specifies in samples the threshold below which the Ready
            for Transfer Event deasserts. This threshold is an amount of
            space available in the onboard memory of the device.
            **rdy_for_xfer_event_deassert_cond** must be
            **DeassertCondition.ONBOARD_MEMORY_CUSTOM_THRESHOLD** to use
            a custom threshold.
        """
        val = ctypes.c_uint()

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

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

        return val.value

def do_num_booleans_per_chan(self):
        """
        int: Indicates the number of Boolean values expected per channel
            in a sample for line-based writes. This property is
            determined by the channel in the task with the most digital
            lines. If a channel has fewer lines than this number, NI-
            DAQmx ignores the extra Boolean values.
        """
        val = ctypes.c_uint()

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

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

        return val.value

def output_buf_size(self):
        """
        int: Specifies the number of samples the output buffer can hold
            for each channel in the task. Zero indicates to allocate no
            buffer. Use a buffer size of 0 to perform a hardware-timed
            operation without using a buffer. Setting this property
            overrides the automatic output buffer allocation that NI-
            DAQmx performs.
        """
        val = ctypes.c_uint()

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

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

        return val.value

def output_onbrd_buf_size(self):
        """
        int: Specifies in samples per channel the size of the onboard
            output buffer of the device.
        """
        val = ctypes.c_uint()

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

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

        return val.value

def raw_data_width(self):
        """
        int: Indicates in bytes the required size of a raw sample to
            write to the task.
        """
        val = ctypes.c_uint()

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

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

        return val.value

def space_avail(self):
        """
        int: Indicates in samples per channel the amount of available
            space in the buffer.
        """
        val = ctypes.c_uint()

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

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

        return val.value

def _read_binary_i_16(
        task_handle, read_array, num_samps_per_chan, timeout,
        fill_mode=FillMode.GROUP_BY_CHANNEL):
    samps_per_chan_read = ctypes.c_int()

    cfunc = lib_importer.windll.DAQmxReadBinaryI16
    if cfunc.argtypes is None:
        with cfunc.arglock:
            if cfunc.argtypes is None:
                cfunc.argtypes = [
                    lib_importer.task_handle, ctypes.c_int, ctypes.c_double,
                    ctypes.c_int,
                    wrapped_ndpointer(dtype=numpy.int16, flags=('C', 'W')),
                    ctypes.c_uint, ctypes.POINTER(ctypes.c_int),
                    ctypes.POINTER(c_bool32)]

    error_code = cfunc(
        task_handle, num_samps_per_chan, timeout, fill_mode.value,
        read_array, numpy.prod(read_array.shape),
        ctypes.byref(samps_per_chan_read), None)
    check_for_error(error_code)

    return samps_per_chan_read.value

def _read_binary_u_16(
        task_handle, read_array, num_samps_per_chan, timeout,
        fill_mode=FillMode.GROUP_BY_CHANNEL):
    samps_per_chan_read = ctypes.c_int()

    cfunc = lib_importer.windll.DAQmxReadBinaryU16
    if cfunc.argtypes is None:
        with cfunc.arglock:
            if cfunc.argtypes is None:
                cfunc.argtypes = [
                    lib_importer.task_handle, ctypes.c_int, ctypes.c_double,
                    ctypes.c_int,
                    wrapped_ndpointer(dtype=numpy.uint16, flags=('C', 'W')),
                    ctypes.c_uint, ctypes.POINTER(ctypes.c_int),
                    ctypes.POINTER(c_bool32)]

    error_code = cfunc(
        task_handle, num_samps_per_chan, timeout, fill_mode.value,
        read_array, numpy.prod(read_array.shape),
        ctypes.byref(samps_per_chan_read), None)
    check_for_error(error_code)

    return samps_per_chan_read.value

def _read_binary_i_32(
        task_handle, read_array, num_samps_per_chan, timeout,
        fill_mode=FillMode.GROUP_BY_CHANNEL):
    samps_per_chan_read = ctypes.c_int()

    cfunc = lib_importer.windll.DAQmxReadBinaryI32
    if cfunc.argtypes is None:
        with cfunc.arglock:
            if cfunc.argtypes is None:
                cfunc.argtypes = [
                    lib_importer.task_handle, ctypes.c_int, ctypes.c_double,
                    ctypes.c_int,
                    wrapped_ndpointer(dtype=numpy.int32, flags=('C', 'W')),
                    ctypes.c_uint, ctypes.POINTER(ctypes.c_int),
                    ctypes.POINTER(c_bool32)]

    error_code = cfunc(
        task_handle, num_samps_per_chan, timeout, fill_mode.value,
        read_array, numpy.prod(read_array.shape),
        ctypes.byref(samps_per_chan_read), None)
    check_for_error(error_code)

    return samps_per_chan_read.value

def _read_binary_u_32(
        task_handle, read_array, num_samps_per_chan, timeout,
        fill_mode=FillMode.GROUP_BY_CHANNEL):
    samps_per_chan_read = ctypes.c_int()

    cfunc = lib_importer.windll.DAQmxReadBinaryU32
    if cfunc.argtypes is None:
        with cfunc.arglock:
            if cfunc.argtypes is None:
                cfunc.argtypes = [
                    lib_importer.task_handle, ctypes.c_int, ctypes.c_double,
                    ctypes.c_int,
                    wrapped_ndpointer(dtype=numpy.uint32, flags=('C', 'W')),
                    ctypes.c_uint, ctypes.POINTER(ctypes.c_int),
                    ctypes.POINTER(c_bool32)]

    error_code = cfunc(
        task_handle, num_samps_per_chan, timeout, fill_mode.value,
        read_array, numpy.prod(read_array.shape),
        ctypes.byref(samps_per_chan_read), None)
    check_for_error(error_code)

    return samps_per_chan_read.value

def _read_digital_u_8(
        task_handle, read_array, num_samps_per_chan, timeout,
        fill_mode=FillMode.GROUP_BY_CHANNEL):
    samps_per_chan_read = ctypes.c_int()

    cfunc = lib_importer.windll.DAQmxReadDigitalU8
    if cfunc.argtypes is None:
        with cfunc.arglock:
            if cfunc.argtypes is None:
                cfunc.argtypes = [
                    lib_importer.task_handle, ctypes.c_int, ctypes.c_double,
                    ctypes.c_int,
                    wrapped_ndpointer(dtype=numpy.uint8, flags=('C', 'W')),
                    ctypes.c_uint, ctypes.POINTER(ctypes.c_int),
                    ctypes.POINTER(c_bool32)]

    error_code = cfunc(
        task_handle, num_samps_per_chan, timeout, fill_mode.value,
        read_array, numpy.prod(read_array.shape),
        ctypes.byref(samps_per_chan_read), None)
    check_for_error(error_code)

    return samps_per_chan_read.value

def _read_digital_u_32(
        task_handle, read_array, num_samps_per_chan, timeout,
        fill_mode=FillMode.GROUP_BY_CHANNEL):
    samps_per_chan_read = ctypes.c_int()

    cfunc = lib_importer.windll.DAQmxReadDigitalU32
    if cfunc.argtypes is None:
        with cfunc.arglock:
            if cfunc.argtypes is None:
                cfunc.argtypes = [
                    lib_importer.task_handle, ctypes.c_int, ctypes.c_double,
                    ctypes.c_int,
                    wrapped_ndpointer(dtype=numpy.uint32, flags=('C', 'W')),
                    ctypes.c_uint, ctypes.POINTER(ctypes.c_int),
                    ctypes.POINTER(c_bool32)]

    error_code = cfunc(
        task_handle, num_samps_per_chan, timeout, fill_mode.value,
        read_array, numpy.prod(read_array.shape),
        ctypes.byref(samps_per_chan_read), None)
    check_for_error(error_code)

    return samps_per_chan_read.value

def _read_digital_scalar_u_32(task_handle, timeout):
    value = ctypes.c_uint()

    cfunc = lib_importer.windll.DAQmxReadDigitalScalarU32
    if cfunc.argtypes is None:
        with cfunc.arglock:
            if cfunc.argtypes is None:
                cfunc.argtypes = [
                    lib_importer.task_handle, ctypes.c_double,
                    ctypes.POINTER(ctypes.c_uint), ctypes.POINTER(c_bool32)]

    error_code = cfunc(
        task_handle, timeout, ctypes.byref(value), None)
    check_for_error(error_code)

    return value.value

def _read_counter_f_64(task_handle, read_array, num_samps_per_chan, timeout):
    samps_per_chan_read = ctypes.c_int()

    cfunc = lib_importer.windll.DAQmxReadCounterF64
    if cfunc.argtypes is None:
        with cfunc.arglock:
            if cfunc.argtypes is None:
                cfunc.argtypes = [
                    lib_importer.task_handle, ctypes.c_int, ctypes.c_double,
                    wrapped_ndpointer(dtype=numpy.float64, flags=('C', 'W')),
                    ctypes.c_uint, ctypes.POINTER(ctypes.c_int),
                    ctypes.POINTER(c_bool32)]

    error_code = cfunc(
        task_handle, num_samps_per_chan, timeout,
        read_array, numpy.prod(read_array.shape),
        ctypes.byref(samps_per_chan_read), None)
    check_for_error(error_code)

    return samps_per_chan_read.value

def _read_counter_u_32(task_handle, read_array, num_samps_per_chan, timeout):
    samps_per_chan_read = ctypes.c_int()

    cfunc = lib_importer.windll.DAQmxReadCounterU32
    if cfunc.argtypes is None:
        with cfunc.arglock:
            if cfunc.argtypes is None:
                cfunc.argtypes = [
                    lib_importer.task_handle, ctypes.c_int, ctypes.c_double,
                    wrapped_ndpointer(dtype=numpy.uint32, flags=('C', 'W')),
                    ctypes.c_uint, ctypes.POINTER(ctypes.c_int),
                    ctypes.POINTER(c_bool32)]

    error_code = cfunc(
        task_handle, num_samps_per_chan, timeout,
        read_array, numpy.prod(read_array.shape),
        ctypes.byref(samps_per_chan_read), None)
    check_for_error(error_code)

    return samps_per_chan_read.value

def _read_counter_u_32_ex(
        task_handle, read_array, num_samps_per_chan, timeout,
        fill_mode=FillMode.GROUP_BY_CHANNEL):
    samps_per_chan_read = ctypes.c_int()

    cfunc = lib_importer.windll.DAQmxReadCounterU32Ex
    if cfunc.argtypes is None:
        with cfunc.arglock:
            if cfunc.argtypes is None:
                cfunc.argtypes = [
                    lib_importer.task_handle, ctypes.c_int, ctypes.c_double,
                    ctypes.c_int,
                    wrapped_ndpointer(dtype=numpy.uint32, flags=('C', 'W')),
                    ctypes.c_uint, ctypes.POINTER(ctypes.c_int),
                    ctypes.POINTER(c_bool32)]

    error_code = cfunc(
        task_handle, num_samps_per_chan, timeout, fill_mode.value,
        read_array, numpy.prod(read_array.shape),
        ctypes.byref(samps_per_chan_read), None)
    check_for_error(error_code)

    return samps_per_chan_read.value

def _read_counter_scalar_u_32(task_handle, timeout):
    value = ctypes.c_uint()

    cfunc = lib_importer.windll.DAQmxReadCounterScalarU32
    if cfunc.argtypes is None:
        with cfunc.arglock:
            if cfunc.argtypes is None:
                cfunc.argtypes = [
                    lib_importer.task_handle, ctypes.c_double,
                    ctypes.POINTER(ctypes.c_uint), ctypes.POINTER(c_bool32)]

    error_code = cfunc(
        task_handle, timeout, ctypes.byref(value), None)
    check_for_error(error_code)

    return value.value

def _read_ctr_freq(
        task_handle, freq, duty_cycle, num_samps_per_chan, timeout,
        interleaved=FillMode.GROUP_BY_CHANNEL):
    samps_per_chan_read = ctypes.c_int()

    cfunc = lib_importer.windll.DAQmxReadCtrFreq
    if cfunc.argtypes is None:
        with cfunc.arglock:
            if cfunc.argtypes is None:
                cfunc.argtypes = [
                    lib_importer.task_handle, ctypes.c_int, ctypes.c_double,
                    ctypes.c_int,
                    wrapped_ndpointer(dtype=numpy.float64, flags=('C', 'W')),
                    wrapped_ndpointer(dtype=numpy.float64, flags=('C', 'W')),
                    ctypes.c_uint, ctypes.POINTER(ctypes.c_int),
                    ctypes.POINTER(c_bool32)]

    error_code = cfunc(
        task_handle, num_samps_per_chan, timeout, interleaved.value,
        freq, duty_cycle, numpy.prod(freq.shape),
        ctypes.byref(samps_per_chan_read), None)
    check_for_error(error_code)

    return samps_per_chan_read.value

def _read_ctr_time(
        task_handle, high_time, low_time, num_samps_per_chan, timeout,
        interleaved=FillMode.GROUP_BY_CHANNEL):
    samps_per_chan_read = ctypes.c_int()

    cfunc = lib_importer.windll.DAQmxReadCtrTime
    if cfunc.argtypes is None:
        with cfunc.arglock:
            if cfunc.argtypes is None:
                cfunc.argtypes = [
                    lib_importer.task_handle, ctypes.c_int, ctypes.c_double,
                    ctypes.c_int,
                    wrapped_ndpointer(dtype=numpy.float64, flags=('C', 'W')),
                    wrapped_ndpointer(dtype=numpy.float64, flags=('C', 'W')),
                    ctypes.c_uint, ctypes.POINTER(ctypes.c_int),
                    ctypes.POINTER(c_bool32)]

    error_code = cfunc(
        task_handle, num_samps_per_chan, timeout, interleaved.value,
        high_time, low_time, numpy.prod(high_time.shape),
        ctypes.byref(samps_per_chan_read), None)
    check_for_error(error_code)

    return samps_per_chan_read.value

def _read_raw(task_handle, read_array, num_samps_per_chan, timeout):
    samples_read = ctypes.c_int()
    number_of_bytes_per_sample = ctypes.c_int()

    cfunc = lib_importer.windll.DAQmxReadRaw
    if cfunc.argtypes is None:
        with cfunc.arglock:
            if cfunc.argtypes is None:
                cfunc.argtypes = [
                    lib_importer.task_handle, ctypes.c_int, ctypes.c_double,
                    wrapped_ndpointer(dtype=read_array.dtype, flags=('C', 'W')),
                    ctypes.c_uint, ctypes.POINTER(ctypes.c_int),
                    ctypes.POINTER(ctypes.c_int), ctypes.POINTER(c_bool32)]

    error_code = cfunc(
        task_handle, num_samps_per_chan, timeout, read_array,
        read_array.nbytes, ctypes.byref(samples_read),
        ctypes.byref(number_of_bytes_per_sample), None)
    check_for_error(error_code)

    return samples_read.value, number_of_bytes_per_sample.value

def avail_samp_per_chan(self):
        """
        int: Indicates the number of samples available to read per
            channel. This value is the same for all channels in the
            task.
        """
        val = ctypes.c_uint()

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

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

        return val.value

def common_mode_range_error_chans(self):
        """
        List[str]: Indicates a list of names of any virtual channels in
            the task for which the device(s) detected a common mode
            range violation. You must read
            **common_mode_range_error_chans_exist** before you read this
            property. Otherwise, you will receive an error.
        """
        cfunc = lib_importer.windll.DAQmxGetReadCommonModeRangeErrorChans
        if cfunc.argtypes is None:
            with cfunc.arglock:
                if cfunc.argtypes is None:
                    cfunc.argtypes = [
                        lib_importer.task_handle, ctypes.c_char_p,
                        ctypes.c_uint]

        temp_size = 2048
        val = ctypes.create_string_buffer(temp_size)

        error_code = cfunc(
            self._handle, val, temp_size)
        check_for_error(error_code)

        return unflatten_channel_string(val.value.decode('ascii'))

def input_buf_size(self):
        """
        int: Specifies the number of samples the input buffer can hold
            for each channel in the task. Zero indicates to allocate no
            buffer. Use a buffer size of 0 to perform a hardware-timed
            operation without using a buffer. Setting this property
            overrides the automatic input buffer allocation that NI-
            DAQmx performs.
        """
        val = ctypes.c_uint()

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

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

        return val.value

def input_onbrd_buf_size(self):
        """
        int: Indicates in samples per channel the size of the onboard
            input buffer of the device.
        """
        val = ctypes.c_uint()

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

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

        return val.value

def num_chans(self):
        """
        int: Indicates the number of channels that DAQmx Read reads from
            the task. This value is the number of channels in the task
            or the number of channels you specify with
            **channels_to_read**.
        """
        val = ctypes.c_uint()

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

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

        return val.value

def raw_data_width(self):
        """
        int: Indicates in bytes the size of a raw sample from the task.
        """
        val = ctypes.c_uint()

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

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

        return val.value