Data Acquisition Module¶
The Data Acquisition Module corresponds to the Data Acquisition tab of the LabOne User Interface. It enables the user to record and align time and frequency domain data from multiple instrument signal sources at a defined data rate. The data may be recorded either continuously or in bursts based upon trigger criteria analogous to the functionality provided by laboratory oscilloscopes.
DAQ Module Acquisition Modes and Trigger Types¶
This section lists the required parameters and special considerations for each trigger mode. For reference documentation of the module’s parameters, please see Data Acquisition Module Node Tree.
The following acquisition modes exists:
| Mode / Trigger Type | Description | Value of type |
|---|---|---|
| Continuous | Continuous recording of data. | 0 |
| Edge | Edge trigger with noise rejection. | 1 |
| Pulse | Pulse width trigger with noise rejection. | 3 |
| Tracking (Edge or Pulse) | Level tracking trigger to compensate for signal drift. | 4 |
| Digital | Digital trigger with bit masking. | 2 |
| Hardware | Trigger on one of the instrument’s hardware trigger channels (not available on HF2). | 6 |
| Pulse Counter | Trigger on the value of an instrument’s pulse counter (requires CNT Option). | 8 |
Continuous Acquisition¶
This mode performs back-to-back recording of the subscribed signal paths. The data is returned by read() in bursts of a defined length (duration). This length is defined either:
- Directly by the user via
/durationfor the case of nearest or linear sampling (specified by/grid/mode). - Set by the module in the case of exact grid mode based on the value of
/grid/colsand the highest sampling rate of all subscribed signal paths.
Acquisition using Level Edge Triggering¶
Parameters specific to edge triggering are:
/level/hysteresis
The user can request automatic calculation of the /level and /hysteresis parameters by setting the /findlevel parameter to 1. Please see Determining the Trigger Level automatically for more information.
The following image explains the Data Acquisition Module’s parameters for an Edge Trigger.
Acquisition using Pulse Triggering¶
Parameters specific to pulse triggering are:
/level/hysteresis/pulse/min/pulse/max
The user can request automatic calculation of the /level and
/hysteresis parameters by setting the /findlevel parameter to 1. Please see Determining the Trigger Level for more information.
The following image explains the Data Acquisition Module’s parameters for a positive Pulse Trigger.
Acquisition using Tracking Edge or Pulse Triggering¶
In addition to the parameters specific to edge and pulse triggers, the parameter that is of particular importance when using a tracking trigger type is:
/bandwidth
Acquisition using Digital Triggering¶
To use the DAQ Module with a digital trigger, it must be configured to use a digital
trigger type (by setting type to 2) and to use the output value of the instrument's
DIO port as it's trigger source. This is achieved by setting /triggernode to the
device node /DEV..../DEMODS/N/SAMPLE.bits. It is important to be aware that the
Data Acquisition Module takes its value for the DIO output from the demodulator sample
field bits, not from a node in the /DEV..../DIOS branch. As such, the specified
demodulator must be enabled and and an appropriate transfer rate configured that meets
the required trigger resolution (the Data Acquisition Module can only resolve triggers
at the resolution of 1//DEV..../DEMODS/N/RATE it is not possible to interpolate a
digital signal to improve trigger resolution and if the incoming trigger pulse on the
DIO port is shorter than this resolution, it may be missed).
The Digital Trigger allows not only the trigger bits (/bits) to be specified but
also a bit mask (/bitmask) in order to allow an arbitrary selection of DIO pins to
supply the trigger signal. When a positive, respectively, negative edge trigger is
used, all of these selected pins must become high, respectively low. The bit mask is
applied as following. For positive edge triggering (/edge set to value 1), the Data
Acquisition Module recording is triggered when the following equality holds for the
DIO value:
(/DEV..../DEMODS/N/SAMPLE.bits BITAND bitmask) == (bits BITAND bitmask)
and this equality has not been met for the previous value in time (the previous sample)
of /DEV..../DEMODS/N/SAMPLE.bits. For negative edge triggering (/edge set to value
2), the Data Acquisition Module recording is triggered when the following inequality
holds for the current DIO value:
(/DEV..../DEMODS/N/SAMPLE.bits BITAND bitmask) != (bits BITAND bitmask)
and this inequality was not met (there was equality) for the previous value of the DIO value.
Acquisition using Hardware Triggering¶
There are no parameters specific only to hardware triggering since the
hardware trigger defines the trigger criterion itself; only the trigger
edge must be specified. For a hardware trigger the
triggernode must be one of:
/DEV.../CNTS/N/SAMPLE.TrigAWGTrigN+ (requires CNT Option)/DEV.../DEMODS/N/SAMPLE.TrigAWGTrigN/DEV.../DEMODS/N/SAMPLE.TrigDemod4Phase/DEV.../DEMODS/N/SAMPLE.TrigDemod8Phase/DEV.../CNTS/N/SAMPLE.TrigInN(requires CNT Option)/DEV.../DEMODS/N/SAMPLE.TrigInN/DEV.../DEMODS/N/SAMPLE.TrigOutN
The hardware trigger type is not supported on HF2 instruments.
Acquisition using Pulse Counter Triggering¶
Pulse Counter triggering requires the CNT Option. Parameters specific to the pulse counter trigger type:
/eventcount/mode
The /triggernode must be configured to be a pulse counter sample /DEV…./CNTS/N/SAMPLE.value.
Determining the Trigger Level automatically¶
The Data Acquisition Module can calculate the /level and /hysteresis
parameters based on the current input signal for edge, pulse, tracking
edge and tracking pulse trigger types. This is particularly useful when
using a tracking trigger, where the trigger level is relative to the
output of the low-pass filter tracking the input signal's average. In the
LabOne User Interface this functionality corresponds to the "Find" button in the
Settings sub-tab of the Data Acquisition Tab.
This functionality is activated via API by setting the /findlevel parameter to 1.
This is a single-shot
calculation of the level and hysteresis parameters, meaning that it is
performed only once, not continually. The Data Acquisition Module
monitors the input signal for a duration of 0.1 seconds and sets the
level parameter to the average of the largest and the smallest values
detected in the signal and the hysteresis to 10% of the difference
between largest and smallest values. When the Data Acquisition Module
has finished its calculation of the level and hysteresis parameters it
sets the value of the /findlevel parameter to 0
and writes the values to the /level and
/hysteresis parameters. Note that the calculation
is only performed if the Data Acquisition Module is currently running,
i.e., after execute() has been called.
The following python code demonstrates how to use the /findlevel parameter.
# Arm the Data Acquisition Module: ready for trigger acquisition.
trigger.execute()
# Tell the Data Acquisition Module to determine the trigger level.
trigger.set('findlevel', 1)
findlevel = 1
timeout = 10 # [s]
t0 = time.time()
while findlevel == 1:
time.sleep(0.05)
findlevel = trigger.getInt('findlevel')
if time.time() - t0 > timeout:
trigger.finish()
trigger.clear()
raise RuntimeError("Data Acquisition Module didn't find trigger level after %.3f seconds." % timeout)
level = trigger.getDouble('level')
hysteresis = trigger.getDouble('hysteresis')
Signal Subscription¶
The Data Acquisition Module uses dot notation for subscribing to the
signals. Whereas with the Software Trigger (Recorder Module) you
subscribe to an entire streaming node, e.g. /DEV..../DEMODS/N/SAMPLE and
get all the signal components of this node back, with the Data
Acquisition Module you specify the exact signal you are interested in
capturing, e.g. /DEV..../DEMODS/N/SAMPLE.r
/DEV..../DEMOD/0/SAMPLE.phase.
In addition, by appending suffixes to the signal path, various
operations can be applied to the source signal and cascaded to obtain
the desired result. Some examples are given below (the
/DEV.../DEMODS/n/SAMPLE prefix has been omitted):
| Signal | Description |
|---|---|
x |
Demodulator sample x component. |
r.avg |
Average of demodulator sample abs(x + iy). |
x.std |
Standard deviation of demodulator sample x component. |
xiy.fft.abs.std |
Standard deviation of complex FFT of x + iy. |
phase.fft.abs.avg |
Average of real FFT of linear corrected phase. |
freq.fft.abs.pwr |
Power of real FFT of frequency. |
r.fft.abs |
Real FFT of abs(x + iy). |
df.fft.abs |
Real FFT of demodulator phase derivative (dθ/dt)/(2π). |
xiy.fft.abs.pwr |
Power of complex FFT of x + iy. |
xiy.fft.abs.filter |
Demodulator low-pass filter transfer function. Divide xiy.fft.abs by this to obtain a compensated FFT. |
The specification for signal subscription is given below, together with the possible options. Angle brackets <> indicate mandatory fields. Square brackets [] indicate optional fields.
<node_path><.source_signal>[.fft<.complex_selector>[.filter]][.pwr][.math_operation]
source_signal
Note
Nodes not listed here probably only contain one signal and do not have a source_signal field.
| Signal Name | Description (Path of the node containing the signal(s)) | Comment |
|---|---|---|
<demod>.x |
Demodulator output in-phase component | |
<demod>.y |
Demodulator output quadrature component | |
<demod>.r |
Demodulator output amplitude | |
<demod>.theta |
Demodulator output phase | |
<demod>.frequency |
Oscillator frequency | |
<demod>.auxin0 |
Auxiliary input channel 1 | |
<demod>.auxin1 |
Auxiliary input channel 2 | |
<demod>.xiy |
Combined demodulator output in-phase and quadrature components | complex output (can only be used as FFT input)) |
<demod>.df |
Demodulator output phase derivative (can only be used for FFT(dθ/dt)/(2π) | |
<impedance>.realz |
In-phase component of impedance sample | |
<impedance>.imagz |
Quadrature component of impedance sample | |
<impedance>.absz |
Amplitude of impedance sample | |
<impedance>.phasez |
Phase of impedance sample | |
<impedance>.frequency |
Oscillator frequency | |
<impedance>.param0 |
Measurement parameter that depends on circuit configuration | |
<impedance>.param1 |
Measurement parameter that depends on circuit configuration | |
<impedance>.drive |
Amplitude of the AC signal applied to the device under test | |
<impedance>.bias |
DC Voltage applied to the device under test | |
<impedance>.z |
Combined impedance in-phase and quadrature components | complex (can only be used as FFT input) |
complex_selector (mandatory with .fft)
| Signal Name | Description |
|---|---|
real |
Real component of FFT |
imag |
Imaginary component of FFT |
abs |
Absolute component of FFT |
phase |
Phase component of FFT |
filter (optional)
Helper signal representing demodulator low-pass filter transfer function. It can only be applied to 'abs' FFT output of complex demodulator source signal, i.e. 'xiy.fft.abs.filter'. No additional operations are permitted. Can be used to compensate the FFT result for the demodulator low-pass filter.
pwr (optional)
Power calculation
math_operation (optional)
| Signal Name | Description |
|---|---|
| avg | Average of grid repetitions (parameter grid/repetitions) |
| std | Standard deviation |
Node Documentation¶
This section describes all the nodes in the Data Acquisition Module node tree organized by branch.
awgcontrol¶
/awgcontrol ¶
| Properties: | Read, Write |
| Type: | Integer (64 bit) |
| Unit: | None |
Enable interaction with the AWG. If enabled, the row number is identified based on the digital row ID number set by the AWG. If disabled, every new trigger event is attributed to a new row sequentially.
bandwidth¶
/bandwidth ¶
| Properties: | Read, Write |
| Type: | Double |
| Unit: | Hz |
Set to a value other than 0 in order to apply a low-pass filter with the specified bandwidth to the triggernode signal before applying the trigger criteria. For edge and pulse trigger use a bandwidth larger than the trigger signal's sampling rate divided by 20 to keep the phase delay. For tracking filter use a bandwidth smaller than the trigger signal's sampling rate divided by 100 to track slow signal components like drifts. The value of the filtered signal is returned by read() under the path /DEV..../TRIGGER/LOWPASS.
bitmask¶
/bitmask ¶
| Properties: | Read, Write |
| Type: | Integer (64 bit) |
| Unit: | None |
Specify a bit mask for the DIO trigger value. The trigger value is bits AND bit mask (bitwise). Only used when the trigger type is digital.
bits¶
/bits ¶
| Properties: | Read, Write |
| Type: | Integer (64 bit) |
| Unit: | None |
Specify the value of the DIO to trigger on. All specified bits have to be set in order to trigger. Only used when the trigger type is digital.
buffercount¶
/buffercount ¶
| Properties: | Read |
| Type: | Integer (64 bit) |
| Unit: | None |
The number of buffers used internally by the module for data recording.
buffersize¶
/buffersize ¶
| Properties: | Read |
| Type: | Double |
| Unit: | Seconds |
The buffersize of the module's internal data buffers.
clearhistory¶
/clearhistory ¶
| Properties: | Read, Write |
| Type: | Integer (64 bit) |
| Unit: | None |
Set to 1 to clear all the acquired data from the module. The module immediately resets clearhistory to 0 after it has been set to 1.
count¶
/count ¶
| Properties: | Read, Write |
| Type: | Integer (64 bit) |
| Unit: | None |
The number of trigger events to acquire in single-shot mode (when endless is set to 0).
delay¶
/delay ¶
| Properties: | Read, Write |
| Type: | Double |
| Unit: | Seconds |
Time delay of trigger frame position (left side) relative to the trigger edge. delay=0: Trigger edge at left border; delay<0: trigger edge inside trigger frame (pretrigger); delay>0: trigger edge before trigger frame (posttrigger)
device¶
/device ¶
| Properties: | Read, Write |
| Type: | String |
| Unit: | None |
The device serial to be used with the Data Acquisition Module, e.g. dev1000 (compulsory parameter).
duration¶
/duration ¶
| Properties: | Read, Write |
| Type: | Double |
| Unit: | Seconds |
The recording length of each trigger event. This is an input parameter when the sampling mode (grid/mode) is either nearest or linear interpolation. In exact sampling mode duration is an output parameter; it is calculated and set by the module based on the value of grid/cols and the highest rate of all the subscribed signal paths.
edge¶
/edge ¶
| Properties: | Read, Write |
| Type: | Integer (enumerated) |
| Unit: | None |
The trigger edge to trigger upon when running a triggered acquisition mode.
| Value | Description |
|---|---|
| 1 | "rising": Rising edge |
| 2 | "falling": Falling edge |
| 3 | "both": Both rising and falling |
enable¶
/enable ¶
| Properties: | Read, Write |
| Type: | Integer (64 bit) |
| Unit: | None |
Set to 1 to enable the module and start data acquisition (is equivalent to calling execute()).
endless¶
/endless ¶
| Properties: | Read, Write |
| Type: | Integer (64 bit) |
| Unit: | None |
Set to 1 to enable endless triggering. Set to 0 and use count if the module should only acquire a certain number of trigger events.
eventcount¶
/eventcount/mode ¶
| Properties: | Read, Write |
| Type: | Integer (enumerated) |
| Unit: | None |
Specifies the trigger mode when the triggernode is configured as a pulse counter sample value (/DEV..../CNTS/0/SAMPLE.value).
| Value | Description |
|---|---|
| 0 | "every_sample": Trigger on every sample from the pulse counter, regardless of the counter value. |
| 1 | "incrementing_counter": Trigger on incrementing counter values. |
fft¶
/fft/absolute ¶
| Properties: | Read, Write |
| Type: | Integer (64 bit) |
| Unit: | None |
Set to 1 to shift the frequencies in the FFT result so that the center frequency becomes the demodulation frequency rather than 0 Hz (when disabled).
/fft/window ¶
| Properties: | Read, Write |
| Type: | Integer (enumerated) |
| Unit: | None |
The FFT window function to use (default 1 = Hann). Depending on the application, it makes a huge difference which of the provided window functions is used. Please check the literature to find out the best trade off for your needs.
| Value | Description |
|---|---|
| 0 | "rectangular": Rectangular |
| 1 | "hann": Hann |
| 2 | "hamming": Hamming |
| 3 | "blackman_harris": Blackman Harris 4 term |
| 16 | "exponential": Exponential (ring-down) |
| 17 | "cos": Cosine (ring-down) |
| 18 | "cos_squared": Cosine squared (ring-down) |
findlevel¶
/findlevel ¶
| Properties: | Read, Write |
| Type: | Integer (64 bit) |
| Unit: | None |
Set to 1 to automatically find appropriate values of the trigger level and hysteresis based on the current triggernode signal value. The module sets findlevel to 0 once the values have been found and set.
flags¶
/flags ¶
| Properties: | Read, Write |
| Type: | Integer (64 bit) |
| Unit: | None |
Record flags. FILL = 0x1: always enabled; ALIGN = 0x2: always enabled; THROW = 0x4: Throw if sample loss is detected; DETECT = 0x8: always enabled.
forcetrigger¶
/forcetrigger ¶
| Properties: | Read, Write |
| Type: | Integer (64 bit) |
| Unit: | None |
Set to 1 to force acquisition of a single trigger for all subscribed signal paths (when running in a triggered acquisition mode). The module immediately resets forcetrigger to 0 after it has been set to 1.
grid¶
/grid/cols ¶
| Properties: | Read, Write |
| Type: | Integer (64 bit) |
| Unit: | None |
Specify the number of columns in the returned data grid (matrix). The data along the horizontal axis is resampled to the number of samples defined by grid/cols. The grid/mode parameter specifies how the data is sample onto the time, respectively frequency, grid.
/grid/direction ¶
| Properties: | Read, Write |
| Type: | Integer (enumerated) |
| Unit: | None |
The direction to organize data in the grid's matrix.
| Value | Description |
|---|---|
| 0 | "forward": Forward. The data in each row is ordered chronologically, e.g., the first data point in each row corresponds to the first timestamp in the trigger data. |
| 1 | "reverse": Reverse. The data in each row is in reverse chronological order, e.g., the first data point in each row corresponds to the last timestamp in the trigger data. |
| 2 | "bidirectional": Bidirectional. The ordering of the data alternates between Forward and Backward ordering from row-to-row. The first row is Forward ordered. |
/grid/mode ¶
| Properties: | Read, Write |
| Type: | Integer (enumerated) |
| Unit: | None |
Specify how the acquired data is sampled onto the matrix's horizontal axis (time or frequency). Each trigger event becomes a row in the matrix and each trigger event's subscribed data is sampled onto the grid defined by the number of columns (grid/cols) and resampled as specified with this parameter.
| Value | Description |
|---|---|
| 1 | "nearest": Use the closest data point (nearest neighbour interpolation). |
| 2 | "linear": Use linear interpolation. |
| 4 | "exact": Do not resample the data from the subscribed signal path(s) with the highest sampling rate; the horizontal axis data points are determined from the sampling rate and the value of grid/cols. Subscribed signals with a lower sampling rate are upsampled onto this grid using linear interpolation. |
/grid/overwrite ¶
| Properties: | Read, Write |
| Type: | Integer (64 bit) |
| Unit: | None |
If enabled, the module will return only one data chunk (grid) when it is running, which will then be overwritten by subsequent trigger events.
/grid/repetitions ¶
| Properties: | Read, Write |
| Type: | Integer (64 bit) |
| Unit: | None |
Number of statistical operations performed per grid. Only applied when the subscribed signal path is, for example, an average or a standard deviation.
/grid/rowrepetition ¶
| Properties: | Read, Write |
| Type: | Integer (64 bit) |
| Unit: | None |
Enable row-wise repetition. With row-wise repetition, each row is calculated from successive repetitions before starting the next row. With grid-wise repetition, the entire grid is calculated with each repetition.
/grid/rows ¶
| Properties: | Read, Write |
| Type: | Integer (64 bit) |
| Unit: | None |
Specify the number of rows in the grid's matrix. Each row is the data recorded from one trigger event.
/grid/waterfall ¶
| Properties: | Read, Write |
| Type: | Integer (64 bit) |
| Unit: | None |
Set to 1 to enable waterfall mode: Move the data upwards upon each trigger event; the data from newest trigger event is placed in row 0.
historylength¶
/historylength ¶
| Properties: | Read, Write |
| Type: | Integer (64 bit) |
| Unit: | None |
Sets an upper limit for the number of data captures stored in the module.
holdoff¶
/holdoff/count ¶
| Properties: | Read, Write |
| Type: | Integer (64 bit) |
| Unit: | None |
The number of skipped trigger events until the next trigger event is acquired.
/holdoff/time ¶
| Properties: | Read, Write |
| Type: | Double |
| Unit: | Seconds |
The hold-off time before trigger acquisition is re-armed again. A hold-off time smaller than the duration will produce overlapped trigger frames.
hysteresis¶
/hysteresis ¶
| Properties: | Read, Write |
| Type: | Double |
| Unit: | Many |
If non-zero, hysteresis specifies an additional trigger criteria to level in the trigger condition. The trigger signal must first go higher, respectively lower, than the hysteresis value and then the trigger level for positive, respectively negative edge triggers. The hysteresis value is applied below the trigger level for positive trigger edge selection. It is applied above for negative trigger edge selection, and on both sides for triggering on both edges. A non-zero hysteresis value is helpful to trigger on the correct edge in the presence of noise to avoid false positives.
level¶
preview¶
/preview ¶
| Properties: | Read, Write |
| Type: | Integer (64 bit) |
| Unit: | None |
If set to 1, enable the data of an incomplete trigger to be read. Useful for long trigger durations (or FFTs) by providing access to the intermediate data.
pulse¶
/pulse/max ¶
| Properties: | Read, Write |
| Type: | Double |
| Unit: | Seconds |
The maximum pulse width to trigger on when using a pulse trigger.
/pulse/min ¶
| Properties: | Read, Write |
| Type: | Double |
| Unit: | Seconds |
The minimum pulse width to trigger on when using a pulse trigger.
refreshrate¶
/refreshrate ¶
| Properties: | Read, Write |
| Type: | Double |
| Unit: | Hz |
Set the maximum refresh rate of updated data in the returned grid. The actual refresh rate depends on other factors such as the hold-off time and duration.
save¶
/save/csvlocale ¶
| Properties: | Read, Write |
| Type: | String |
| Unit: | None |
The locale to use for the decimal point character and digit grouping character for numerical values in CSV files: "C": Dot for the decimal point and no digit grouping (default); "" (empty string): Use the symbols set in the language and region settings of the computer.
/save/csvseparator ¶
| Properties: | Read, Write |
| Type: | String |
| Unit: | None |
The character to use as CSV separator when saving files in this format.
/save/directory ¶
| Properties: | Read, Write |
| Type: | String |
| Unit: | None |
The base directory where files are saved.
/save/fileformat ¶
| Properties: | Read, Write |
| Type: | Integer (enumerated) |
| Unit: | None |
The format of the file for saving data.
| Value | Description |
|---|---|
| 0 | "mat": MATLAB |
| 1 | "csv": CSV |
| 2 | "zview": ZView (Impedance data only) |
| 3 | "sxm": SXM (Image format) |
| 4 | "hdf5": HDF5 |
/save/filename ¶
| Properties: | Read, Write |
| Type: | String |
| Unit: | None |
Defines the sub-directory where files are saved. The actual sub-directory has this name with a sequence count (per save) appended, e.g. daq_000.
/save/save ¶
| Properties: | Read, Write |
| Type: | Integer (64 bit) |
| Unit: | None |
Initiate the saving of data to file. The saving is done in the background. When the save has finished, the module resets this parameter to 0.
/save/saveonread ¶
| Properties: | Read, Write |
| Type: | Integer (64 bit) |
| Unit: | None |
Automatically save the data to file immediately before reading out the data from the module using the read() command. Set this parameter to 1 if you want to save data to file when running the module continuously and performing intermediate reads.
spectrum¶
/spectrum/autobandwidth ¶
| Properties: | Read, Write |
| Type: | Integer (64 bit) |
| Unit: | None |
Set to 1 to initiate automatic adjustment of the subscribed demodulator bandwidths to obtain optimal alias rejection for the selected frequency span which is equivalent to the sampling rate. The FFT mode has to be enabled (spectrum/enable) and the module has to be running for this function to take effect. The module resets spectrum/autobandwidth to 0 when the adjustment has finished.
/spectrum/enable ¶
| Properties: | Read, Write |
| Type: | Integer (64 bit) |
| Unit: | None |
Enables the FFT mode of the data Acquisition module, in addition to time domain data acquisition. Note that when the FFT mode is enabled, the grid/cols parameter value is rounded down to the nearest binary power.
/spectrum/frequencyspan ¶
| Properties: | Read, Write |
| Type: | Double |
| Unit: | None |
Sets the desired frequency span of the FFT.
/spectrum/overlapped ¶
| Properties: | Read, Write |
| Type: | Integer (64 bit) |
| Unit: | None |
Enables overlapping FFTs. If disabled (0), FFTs are performed on distinct abutting data sets. If enabled, the data sets of successive FFTs overlap based on the defined refresh rate.
triggered¶
/triggered ¶
| Properties: | Read |
| Type: | Integer (64 bit) |
| Unit: | None |
Indicates whether the module has recently triggered: 1=Yes, 0=No.
triggernode¶
/triggernode ¶
| Properties: | Read, Write |
| Type: | String |
| Unit: | None |
The node path and signal that should be used for triggering, the node path and signal should be separated by a dot (.), e.g. /DEV.../DEMODS/0/SAMPLE.X.
type¶
/type ¶
| Properties: | Read, Write |
| Type: | Integer (enumerated) |
| Unit: | None |
Specifies how the module acquires data.
| Value | Description |
|---|---|
| 0 | "continuous": Continuous acquisition (trigger off). |
| 1 | "analog_edge_trigger": Analog edge trigger. |
| 2 | "digital_trigger": Digital trigger mode (on DIO source). |
| 3 | "analog_pulse_trigger": Analog pulse trigger. |
| 4 | "analog_tracking_trigger": Analog tracking trigger. |
| 5 | "change_trigger": Change trigger. |
| 6 | "hardware_trigger": Hardware trigger (on trigger line source). |
| 7 | "pulse_tracking_trigger": Pulse tracking trigger, see also bandwidth. |
| 8 | "event_count_trigger": Event count trigger (on pulse counter source). |
| 9 | "burst_trigger": Burst trigger (device triggered acquisition). |