Liquid Instruments Moku Pro Data Logger User Manual
- June 9, 2024
- Liquid instruments
Table of Contents
Liquid Instruments Moku Pro Data Logger
The Moku:
Pro Data Logger instrument records time series voltages from up to four
channels at rates from 10 samples per second up to 10 MSa/s. The data can be
logged to the onboard SSD storage or can be streamed directly to the computer
using the Moku API.
- The resulting logs can be shared to email or cloud services such as iCloud or Dropbox.
- The Moku: Pro Data Logger also includes an embedded four-channel waveform generator.
Ensure Moku:
The Pro is fully updated. For the latest information, visit
liquidinstruments.com.
User Interface
| ID | Button/icon | Description |
|---|---|---|
| 1 | Main menu | The main menu contains controls for switching instruments, |
switching devices, selecting device clock and user interface modes, and more.
See Main Menu.
2| Autoscale| Toggle continuous autoscaling on/off.
3| Ref| Capture/clear a reference trace.
4| Time window| Overview of the logging time history. Drag bars to
zoom/select different timescales/time windows.
5| Settings| Show/hide the settings.
6| Clear| Clear the trace history.
7| Signal display| Data traces are displayed in this area. By default,
red represents channel 1, blue represents channel 2, teal represents channel
3, yellow green represents channel 4.
8| Bottom left| Double tap here to view entire log history.
9| Grid| Double tap on the grid to on-time autoscale.
Main Menu
The main menu can be accessed by pressing the icon, allowing you to: 
Preferences
The preferences pane can be accessed via the main menu. In here, you can reassign the color representations for each channel, connect to Dropbox, etc. Throughout the manual, the default colors (shown in the figure below) are used to present instrument features.
| ID | Description |
|---|---|
| 1 | Tap to change the color associated with input channels. |
| 2 | Tap to change the color associated with output channels. |
| 3 | Tap to change the color associated with math channel. |
| 4 | Indicate touch points on the screen with circles. This can be useful |
for demonstrations.
5| Change the currently linked Dropbox account to which data can be
uploaded.
6| Notify when a new version of the app is available.
7| Moku:Pro automatically saves instrument settings when exiting the
app, and restores them again at launch. When disabled, all settings will be
reset to defaults on launch.
8| Moku:Pro can remember the last used instrument and automatically
reconnect to it at launch. When disabled, you will need to manually connect
every time.
9| Reset all instruments to their default state.
10| Save and apply settings.
Data Logger control panel
Below the main Data Logger trace display is the control panel.
| ID | Button/icon | Description |
|---|---|---|
| 1 | Status | Logger status, either idle, aborted, waiting, or logging. |
| 2 | Share | The sharing button gives access to controls that allow you to |
save and share your data. See Saving and sharing data.
3| Memory| Displays the used and remaining memory available for logging.
4| Mode| Set acquisition mode as normal or precision.
5| Filename| Configure the prefix to be used on the data filename.
6| Comment| Text entered here will be saved in the file header.
7| Start/stop| Tap to start and top data logging.
8| Log format| Tap to select log format, CSV or LI binary format.
9| Duration| Tap to set log duration, up to 10,000 hours1.
10| Start| Tap to configure start delay, up to 240 hrs.
11| Acquisition rate| Tap to configure the acquisition rate.
Sharing and saving data
Tap the share button to access the file manager, allowing the saving and sharing of the captured data logs. Dropbox, Mail, and iCloud service settings are configured in the iPad preferences.
| ID | Button/icon | Description |
|---|---|---|
| 1 | All | Tap to select all files. |
| 2 | None | Tap to deselect all files. |
| 3 | Save options | Tap to share data files to “My Files” or any of these |
online services.
Settings
Acquisition
The acquisition sidebar configures the acquisition parameters of both input
channels. The channel 1, channel 2, channel 3, channel 4, and acquisitions
sub-panels may be dragged into the main display by tap/hold and drag.
| ID | Button | Description |
|---|---|---|
| 1 | Channels 1 settings | Channel 1 (red by default; configurable in main |
menu preferences), channel 2, channel 3, and channel 4 settings are
configurable independently.
2| Coupling| Select AC or DC coupling.
3| Impedance| Select high 1 MΩ or 50 Ω input impedance.
4| Range| Selects the input range, one of 400 mV, 4 V, or 40 V peak-to-
peak.
5–8| Channel 2 settings| Configure channel 2 as described above for
channel 1.
9| Acquisition settings| Configure acquisition settings.
10| Rate| Adjust the data acquisition rate.
11| Mode| Precision, normal.
Output
The Moku:
Pro Data Logger has a built-in waveform generator capable of generating basic
waveforms on the four output channels. For more complex waveforms, see the
Moku:Pro Waveform Generator and Arbitrary Waveform Generator user manuals
.
| ID | Button | Description |
|---|---|---|
| 1 | Configure channels | Tap to configure settings for channels 1 to 4. As |
illustrated, settings apply to channel 1.
2| Current waveform| Graphical representation of the selected waveform.
3| Waveform selection| Tap to choose between Sine, Square, Ramp, Pulse,
or DC waveforms.
4| Enable| Tap to enable/disable channel output.
5| Load| Tap to select either 50 Ω or 1 MΩ output load.
6| Waveform parameters| Tap to configure the selected waveform
parameters varying according the waveform type selected.
Instrument Reference
The Moku:Pro Data Logger is designed to be intuitive and straightforward to use. Up to four channels of time-series voltages are recorded by Moku:Pro, for a specified duration, and at a specified rate.
Recording a Session
Recording data is done as follows:
- Configure the channel(s) you wish to record using the acquisition sidebar. Ensure the voltage range, coupling, and impedance are all appropriate for your signals. Use the plotter window to ensure your signal is correctly connected and configured.
- Configure the acquisition rate and acquisition mode, either normal or precision.
- Set the recording duration and any comments you want to be saved with the file.
- Optionally configure the waveform generator outputs.
- Tap “record”.
Channel Configuration
Each channel can be enabled or disabled, set to a maximum range of 400 mVpp, 4
Vpp, or 40Vpp, AC or DC-coupled, and 50 Ω or 1 MΩ terminated.
Acquisition Parameters
The acquisition parameters refer to the logging rate and the down-sampling
mode used to reduce the Moku: Pro native sampling rate to the logging rate.
The logging rate must be between 10 Sa/s and 10 MSa/s. The maximum logging
rate is 10 MSa/s for 1 channel, 5 MSa/s for 2 channels, and 2.5 MSa/s for 4
channels. Acquisition mode may be either normal or precise. Normal mode down-
samples by discarding points between those needed. This causes signals to
alias; not desirable for most signals but can be useful for viewing frequency
components outside the logging rate.
Precision mode down-samples by averaging, increasing precision, and reducing noise. This mode is preferred for most applications.
File Types
The binary file format is proprietary to Moku: Pro and has been optimized for
speed and size. Using the binary format, Moku: Pro is able to reach very high
logging rates and very low memory usage.
The binary file can be converted to other formats by the iPad app or the file converter software available from the Liquid Instruments website. This software can convert the binary file to CSV, MATLAB, or NPY formats for access in major scientific software.
Starting the Log
The red record button should be tapped to start. The status indicator at the
top of the control panel will display logging progress.
The log will stop either when the specified duration has been reached, or when the user taps the record button again to abort.
Data streaming
When configured through the Moku API, the Data Logger can stream over a
network, instead of saving directly to the device. More streaming information
is in our API documents at
apis.liquidinstruments.com.
Accessing your Data
Data logs can be shared to My Files, Dropbox, Mail, or iCloud. Refer to
Sharing and saving data above.
Ensure Moku:
The Pro is fully updated. For the latest information, visit
www.liquidinstruments.com.
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