nidaqmx.task.timing
- class nidaqmx._task_modules.timing.Timing(task_handle, interpreter)[source]
Bases:
objectRepresents the timing configurations for a DAQmx task.
- property ai_conv_active_edge
Specifies on which edge of the clock pulse an analog-to-digital conversion takes place.
- property ai_conv_dig_fltr_enable
Specifies whether to apply a digital filter to the AI Convert Clock.
- Type
bool
- property ai_conv_dig_fltr_min_pulse_width
Specifies in seconds the minimum pulse width the filter recognizes.
- Type
float
- property ai_conv_dig_fltr_timebase_rate
Specifies in hertz the rate of the digital filter timebase. NI-DAQmx uses this value to compute settings for the filter.
- Type
float
- property ai_conv_dig_fltr_timebase_src
Specifies the terminal of the signal to use as the timebase of the digital filter.
- Type
str
- property ai_conv_dig_sync_enable
Specifies whether to synchronize recognition of transitions in the signal to the internal timebase of the device.
- Type
bool
- property ai_conv_max_rate
Indicates the maximum convert rate supported by the task, given the current devices and channel count.
- Type
float
- property ai_conv_rate
Specifies in Hertz the rate at which to clock the analog- to-digital converter. This clock is specific to the analog input section of multiplexed devices.
- Type
float
- property ai_conv_src
Specifies the terminal of the signal to use as the AI Convert Clock.
- Type
str
- property ai_conv_timebase_div
Specifies the number of AI Convert Clock Timebase pulses needed to produce a single AI Convert Clock pulse.
- Type
int
- property ai_conv_timebase_src
Specifies the terminal of the signal to use as the AI Convert Clock Timebase.
- cfg_burst_handshaking_timing_export_clock(sample_clk_rate, sample_clk_outp_term, sample_mode=AcquisitionType.FINITE, samps_per_chan=1000, sample_clk_pulse_polarity=Polarity.ACTIVE_HIGH, pause_when=Level.HIGH, ready_event_active_level=Polarity.ACTIVE_HIGH)[source]
Configures when the DAQ device transfers data to a peripheral device, using the onboard Sample Clock of the DAQ device to control burst handshake timing and exporting that clock for use by the peripheral device.
- Parameters
sample_clk_rate (float) – Specifies in hertz the rate of the Sample Clock.
sample_clk_outp_term (str) – Specifies the terminal to which to export the Sample Clock.
sample_mode (Optional[nidaqmx.constants.AcquisitionType]) – Specifies if the task acquires or generates samples continuously or if it acquires or generates a finite number of samples.
samps_per_chan (Optional[int]) – Specifies the number of samples to acquire or generate for each channel in the task if sample_mode is FINITE_SAMPLES. If sample_mode is CONTINUOUS_SAMPLES, NI-DAQmx uses this value to determine the buffer size. This function returns an error if the specified value is negative.
sample_clk_pulse_polarity (Optional[nidaqmx.constants.Polarity]) – Specifies the polarity of the exported Sample Clock.
pause_when (Optional[nidaqmx.constants.Level]) – Specifies whether the task pauses while the trigger signal is high or low.
ready_event_active_level (Optional[nidaqmx.constants.Polarity]) – Specifies the polarity of the Ready for Transfer Event.
- cfg_burst_handshaking_timing_import_clock(sample_clk_rate, sample_clk_src, sample_mode=AcquisitionType.FINITE, samps_per_chan=1000, sample_clk_active_edge=Edge.RISING, pause_when=Level.HIGH, ready_event_active_level=Polarity.ACTIVE_HIGH)[source]
Configures when the DAQ device transfers data to a peripheral device, using an imported sample clock to control burst handshake timing.
- Parameters
sample_clk_rate (float) – Specifies in hertz the rate of the Sample Clock.
sample_clk_src (str) – Specifies the source terminal of the Sample Clock. Leave this input unspecified to use the default onboard clock of the device.
sample_mode (Optional[nidaqmx.constants.AcquisitionType]) – Specifies if the task acquires or generates samples continuously or if it acquires or generates a finite number of samples.
samps_per_chan (Optional[int]) – Specifies the number of samples to acquire or generate for each channel in the task if sample_mode is FINITE_SAMPLES. If sample_mode is CONTINUOUS_SAMPLES, NI-DAQmx uses this value to determine the buffer size. This function returns an error if the specified value is negative.
sample_clk_active_edge (Optional[nidaqmx.constants.Edge]) – Specifies on which edges of Sample Clock pulses to acquire or generate samples.
pause_when (Optional[nidaqmx.constants.Level]) – Specifies whether the task pauses while the trigger signal is high or low.
ready_event_active_level (Optional[nidaqmx.constants.Polarity]) – Specifies the polarity of the Ready for Transfer Event.
- cfg_change_detection_timing(rising_edge_chan='', falling_edge_chan='', sample_mode=AcquisitionType.FINITE, samps_per_chan=1000)[source]
Configures the task to acquire samples on the rising and/or falling edges of the lines or ports you specify. To detect both rising and falling edges on a line or port, specify the name of that line or port to both rising_edge_chan and falling_edge_chan.
- Parameters
rising_edge_chan (Optional[str]) – Specifies the names of the digital lines or ports on which to detect rising edges. The DAQmx physical channel constant lists all lines and ports for devices installed in your system.
falling_edge_chan (Optional[str]) – Specifies the names of the digital lines or ports on which to detect falling edges. The DAQmx physical channel constant lists all lines and ports for devices installed in your system.
sample_mode (Optional[nidaqmx.constants.AcquisitionType]) – Specifies if the task acquires samples continuously or if it acquires a finite number of samples.
samps_per_chan (Optional[int]) – Specifies the number of samples to acquire from each channel in the task if sample_mode is FINITE_SAMPLES. This function returns an error if the specified value is negative.
- cfg_handshaking_timing(sample_mode=AcquisitionType.FINITE, samps_per_chan=1000)[source]
Determines the number of digital samples to acquire or generate using digital handshaking between the device and a peripheral device.
- Parameters
sample_mode (Optional[nidaqmx.constants.AcquisitionType]) – Specifies if the task acquires or generates samples continuously or if it acquires or generates a finite number of samples.
samps_per_chan (Optional[int]) – Specifies the number of samples to acquire or generate for each channel in the task if sample_mode is FINITE_SAMPLES. If sample_mode is CONTINUOUS_SAMPLES, NI-DAQmx uses this value to determine the buffer size. This function returns an error if the specified value is negative.
- cfg_implicit_timing(sample_mode=AcquisitionType.FINITE, samps_per_chan=1000)[source]
Sets only the number of samples to acquire or generate without specifying timing. Typically, you should use this instance when the task does not require sample timing, such as tasks that use counters for buffered frequency measurement, buffered period measurement, or pulse train generation. For finite counter output tasks, samps_per_chan is the number of pulses to generate.
- Parameters
sample_mode (Optional[nidaqmx.constants.AcquisitionType]) – Specifies if the task acquires or generates samples continuously or if it acquires or generates a finite number of samples.
samps_per_chan (Optional[int]) – Specifies the number of samples to acquire or generate for each channel in the task if sample_mode is FINITE_SAMPLES. If sample_mode is CONTINUOUS_SAMPLES, NI-DAQmx uses this value to determine the buffer size. This function returns an error if the specified value is negative.
- cfg_pipelined_samp_clk_timing(rate, source='', active_edge=Edge.RISING, sample_mode=AcquisitionType.FINITE, samps_per_chan=1000)[source]
Sets the source of the Sample Clock, the rate of the Sample Clock, and the number of samples to acquire or generate. The device acquires or generates samples on each Sample Clock edge, but it does not respond to certain triggers until a few Sample Clock edges later. Pipelining allows higher data transfer rates at the cost of increased trigger response latency. Refer to the device documentation for information about which triggers pipelining affects. This timing type allows handshaking using the Pause trigger and either the Ready for Transfer event or the Data Active event. Refer to the device documentation for more information. This timing type is supported only by the NI 6536 and NI 6537.
- Parameters
rate (float) – Specifies the sampling rate in samples per channel per second. If you use an external source for the Sample Clock, set this input to the maximum expected rate of that clock.
source (Optional[str]) – Specifies the source terminal of the Sample Clock. Leave this input unspecified to use the default onboard clock of the device.
active_edge (Optional[nidaqmx.constants.Edge]) – Specifies on which edges of Sample Clock pulses to acquire or generate samples.
sample_mode (Optional[nidaqmx.constants.AcquisitionType]) – Specifies if the task acquires or generates samples continuously or if it acquires or generates a finite number of samples.
samps_per_chan (Optional[int]) – Specifies the number of samples to acquire or generate for each channel in the task if sample_mode is FINITE_SAMPLES. If sample_mode is CONTINUOUS_SAMPLES, NI-DAQmx uses this value to determine the buffer size. This function returns an error if the specified value is negative.
- cfg_samp_clk_timing(rate, source='', active_edge=Edge.RISING, sample_mode=AcquisitionType.FINITE, samps_per_chan=1000)[source]
Sets the source of the Sample Clock, the rate of the Sample Clock, and the number of samples to acquire or generate.
- Parameters
rate (float) – Specifies the sampling rate in samples per channel per second. If you use an external source for the Sample Clock, set this input to the maximum expected rate of that clock.
source (Optional[str]) – Specifies the source terminal of the Sample Clock. Leave this input unspecified to use the default onboard clock of the device.
active_edge (Optional[nidaqmx.constants.Edge]) – Specifies on which edges of Sample Clock pulses to acquire or generate samples.
sample_mode (Optional[nidaqmx.constants.AcquisitionType]) – Specifies if the task acquires or generates samples continuously or if it acquires or generates a finite number of samples.
samps_per_chan (Optional[int]) – Specifies the number of samples to acquire or generate for each channel in the task if sample_mode is FINITE_SAMPLES. If sample_mode is CONTINUOUS_SAMPLES, NI-DAQmx uses this value to determine the buffer size. This function returns an error if the specified value is negative.
- property change_detect_di_falling_edge_physical_chans
nidaqmx.system.physical_channel.PhysicalChannel: Specifies the names of the digital lines or ports on which to detect falling edges. The lines or ports must be used by virtual channels in the task. You also can specify a string that contains a list or range of digital lines or ports.
- property change_detect_di_rising_edge_physical_chans
nidaqmx.system.physical_channel.PhysicalChannel: Specifies the names of the digital lines or ports on which to detect rising edges. The lines or ports must be used by virtual channels in the task. You also can specify a string that contains a list or range of digital lines or ports.
- property change_detect_di_tristate
Specifies whether to tristate lines specified with change_detect_di_rising_edge_physical_chans and change_detect_di_falling_edge_physical_chans that are not in a virtual channel in the task. If you set this property to True, NI-DAQmx tristates rising/falling edge lines that are not in a virtual channel in the task. If you set this property to False, NI-DAQmx does not modify the configuration of rising/falling edge lines that are not in a virtual channel in the task, even if the lines were previously tristated. Set this property to False to detect changes on lines in other tasks or to detect changes on output-only lines.
- Type
bool
- property delay_from_samp_clk_delay
Specifies the amount of time to wait after receiving a Sample Clock edge before beginning to acquire the sample. This value is in the units you specify with delay_from_samp_clk_delay_units.
- Type
float
- property delay_from_samp_clk_delay_units
Specifies the units of delay_from_samp_clk_delay.
- property first_samp_timestamp_enable
Specifies whether to enable the first sample timestamp.
- Type
bool
- property first_samp_timestamp_timescale
Specifies the timescale to be used for the first sample timestamp.
- property hshk_delay_after_xfer
Specifies the number of seconds to wait after a handshake cycle before starting a new handshake cycle.
- Type
float
- property hshk_sample_input_data_when
Specifies on which edge of the Handshake Trigger an input task latches the data from the peripheral device.
- property hshk_start_cond
Specifies the point in the handshake cycle that the device is in when the task starts.
- property implicit_underflow_behavior
Specifies the action to take when the onboard memory of the device becomes empty.
- property master_timebase_rate
Specifies the rate of the Master Timebase.
- Type
float
- property master_timebase_src
Specifies the terminal of the signal to use as the Master Timebase. On an E Series device, you can choose only between the onboard 20MHz Timebase or the RTSI7 terminal.
- Type
str
- property ref_clk_rate
Specifies the frequency of the Reference Clock.
- Type
float
- property ref_clk_src
Specifies the terminal of the signal to use as the Reference Clock.
- Type
str
- property samp_clk_active_edge
Specifies on which edge of a clock pulse sampling takes place. This property is useful primarily when the signal you use as the Sample Clock is not a periodic clock.
- property samp_clk_dig_fltr_enable
Specifies whether to apply the pulse width filter to the signal.
- Type
bool
- property samp_clk_dig_fltr_min_pulse_width
Specifies in seconds the minimum pulse width the filter recognizes.
- Type
float
- property samp_clk_dig_fltr_timebase_rate
Specifies in hertz the rate of the pulse width filter timebase. NI-DAQmx uses this value to compute settings for the filter.
- Type
float
- property samp_clk_dig_fltr_timebase_src
Specifies the input terminal of the signal to use as the timebase of the pulse width filter.
- Type
str
- property samp_clk_dig_sync_enable
Specifies whether to synchronize recognition of transitions in the signal to the internal timebase of the device.
- Type
bool
- property samp_clk_max_rate
Indicates the maximum Sample Clock rate supported by the task, based on other timing settings. For output tasks, the maximum Sample Clock rate is the maximum rate of the DAC. For input tasks, NI-DAQmx calculates the maximum sampling rate differently for multiplexed devices than simultaneous sampling devices.
- Type
float
- property samp_clk_overrun_behavior
Specifies the action to take if Sample Clock edges occur faster than the device can handle them.
- property samp_clk_rate
Specifies the sampling rate in samples per channel per second. If you use an external source for the Sample Clock, set this input to the maximum expected rate of that clock.
- Type
float
- property samp_clk_src
Specifies the terminal of the signal to use as the Sample Clock.
- Type
str
- property samp_clk_term
Indicates the name of the internal Sample Clock terminal for the task. This property does not return the name of the Sample Clock source terminal specified with samp_clk_src.
- Type
str
- property samp_clk_timebase_active_edge
Specifies on which edge to recognize a Sample Clock Timebase pulse. This property is useful primarily when the signal you use as the Sample Clock Timebase is not a periodic clock.
- property samp_clk_timebase_div
Specifies the number of Sample Clock Timebase pulses needed to produce a single Sample Clock pulse.
- Type
int
- property samp_clk_timebase_master_timebase_div
Specifies the number of pulses of the Master Timebase needed to produce a single pulse of the Sample Clock Timebase.
- Type
int
- property samp_clk_timebase_rate
Specifies the rate of the Sample Clock Timebase. Some applications require that you specify a rate when you use any signal other than the onboard Sample Clock Timebase. NI- DAQmx requires this rate to calculate other timing parameters.
- Type
float
- property samp_clk_timebase_src
Specifies the terminal of the signal to use as the Sample Clock Timebase.
- Type
str
- property samp_clk_timebase_term
Indicates the name of the internal Sample Clock Timebase terminal for the task. This property does not return the name of the Sample Clock Timebase source terminal specified with samp_clk_timebase_src.
- Type
str
- property samp_clk_underflow_behavior
Specifies the action to take when the onboard memory of the device becomes empty. In either case, the sample clock does not stop.
- property samp_clk_write_wfm_use_initial_wfm_dt
Specifies that the value of samp_clk_rate will be determined by the dt component of the initial DAQmx Write waveform input for Output tasks.
- Type
bool
- property samp_quant_samp_mode
Specifies if a task acquires or generates a finite number of samples or if it continuously acquires or generates samples.
- property samp_quant_samp_per_chan
Specifies the number of samples to acquire or generate for each channel if samp_quant_samp_mode is AcquisitionType.FINITE. If samp_quant_samp_mode is AcquisitionType.CONTINUOUS, NI-DAQmx uses this value to determine the buffer size.
- Type
int
- property samp_timing_engine
Specifies which timing engine to use for the task.
- Type
int
- property samp_timing_type
Specifies the type of sample timing to use for the task.
- property simultaneous_ao_enable
Specifies whether to update all channels in the task simultaneously, rather than updating channels independently when you write a sample to that channel.
- Type
bool
- property sync_clk_interval
Specifies the interval, in Sample Clock periods, between each internal Synchronization Clock pulse. NI-DAQmx uses this pulse for synchronization of triggers between multiple devices at different rates. Refer to device documentation for information about how to calculate this value.
- Type
int
- property sync_pulse_min_delay_to_start
Specifies in seconds the amount of time that elapses after the master device issues the synchronization pulse before the task starts.
- Type
float
- property sync_pulse_reset_delay
Specifies in seconds the amount of time to wait after the Synchronization Pulse before resetting the ADCs or DACs on the device. When synchronizing devices, query sync_pulse_reset_time on all devices and note the largest reset time. Then, for each device, subtract the reset time from the largest reset time and set this property to the resulting value.
- Type
float
- property sync_pulse_reset_time
Indicates in seconds the amount of time required for the ADCs or DACs on the device to reset. When synchronizing devices, query this property on all devices and note the largest reset time. Then, for each device, subtract the value of this property from the largest reset time and set sync_pulse_reset_delay to the resulting value.
- Type
float
- property sync_pulse_src
Specifies the terminal of the signal to use as the synchronization pulse. The synchronization pulse resets the clock dividers and the ADCs/DACs on the device.
- Type
str
- property sync_pulse_sync_time
Indicates in seconds the delay required to reset the ADCs/DACs after the device receives the synchronization pulse.
- Type
float
- property sync_pulse_term
Indicates the name of the internal Synchronization Pulse terminal for the task. This property does not return the name of the source terminal.
- Type
str
- property sync_pulse_time_timescale
Specifies the timescale to be used for timestamps for a sync pulse.
- property sync_pulse_type
Specifies the type of sync pulse used in the task.