Logging to PC

Log4 measurements can be viewed through the Log4.Desktop application.

Connecting Log4.USB with Log4.Desktop

  • Connect the Log4 device to PC, then open the Log4.Desktop (Fig. 44).

Log4.Desktop Main Window

Fig. 44 Log4.Desktop Main Window

  • Click on a device in the devices pane, and then select Connect. The device will begin streaming measurement data through to the Log.Desktop app (Fig. 45).

Log4.Desktop functionalities

Log4.Desktop on establishing connection with device

Fig. 45 Log4.Desktop on establishing connection with device

Table below gives the breakdown summary of the Log4.Desktop functionalities as seen in (Fig. 45).

Table 3 Log4 Desktop breakdown


File Tab

  • Import: Import a session logging onto an SD card as a CSV file and view it in the Log4.Desktop app

  • Save as CSV: Save current readings to a CSV file

  • Save as PNG: Save the History View as a PNG file

  • Exit: Close Application


Tools Tab

  • Device Details: Specifications of the connected device

  • Firmware Update: Check for firmware updates on the connected device

  • Settings: Allows editing of some app preferences

  • Log conversion: Tool to convert binary logs exported for the Log4 device to CSV files


Help Tab

Link to Tektyte online documentation website, as well as acknowledgements, app info, and checking for app updates.


Source Options

Allows the choice between streaming data from a currently connected device, or viewing data collected in previous sessions.


Close Button

Close the current connection. Clicking this will save the current history to the app and it will be able to be viewed later.


Display Scale

Displays the scale factor for the measurement display.


History View

Displays session data for the selected measurement.


Sampling Interval Control

Control to change the sampling rate of the connected device.


Measurement Selection

Select the measurement to display (from Current, Voltage, and Power). Also enables selection of the display unit.


Stop monitoring Button

Toggles the live updating of new measurements to the screen.


Reset Button

Resets the History View display.


Detailed Information View

Display area for the detailed information, being Zoom, Histogram, or Statistics View.


Detailed View Options

Controls to display the selected detailed views. These are:

  • Zoom: View a zoomed in view of the measurement selection/last 100 samples.

  • Histogram: View a histogram over the measurement selection/last 100 samples.

  • Statistics: View statistics for the measurement selection/last 100 samples.

  • Plus/Minus Buttons: Zoom in/out the measurement selection.

Measurement selection is made by clicking and dragging an area on the history view. If an area is selected, the detailed view will display details over that period. To de-select an area, double click on the history view. With no selection made, the measurement selection will use the last 100 data points. Dragging the zoom view if a measurement selection has been made will move forwards and backwards in time.


Export menu

Allows exporting the current session as a CSV or PNG file.


Connection display

Displays the serial port and baud rate of the device connection.


Current Date and Time

Displays the current date and time.


Light/Dark mode toggle

Toggles the application between light and dark mode display.

Past Session View

Once you have logged sessions in the Log4.Desktop app, you can view them in the future via the Sessions Tab. A session can be selected by clicking Display Data like when connecting to a device. (Fig. 46)

Session view

Fig. 46 Past session view

When viewing a session, the same controls are available as when viewing the data from a connected device, except for Sample Interval, Monitoring, and Reset controls.

Export Menu

Data can be exported from the Log4.Desktop app in either CSV or PNG format. Either History View or Zoom View screens can be exported, and the choice is made through the dropdown menu.

  • CSV export will export all measurement data in the same format as the SD card logs. The length of the CSV files is given by the length chosen in Tools > App Settings > Max Rows in a CSV File, and multiple files may be produced depending on the length of the session.

  • PNG export will export the currently shown graph, and so will include only one of Current, Voltage, and Power. To change the selected measurement, use the Measurement Selection dropdown.

Firmware Update

The Log4.Desktop app will prompt you to update a device if your firmware is out of date. If you choose not to update, you can update at a later time by disconnecting and reconnecting the device, or by selecting the Tools > Firmware Update menu:

  • Make sure the Log4 device is connected to the computer via micro USB cable.

  • Open Log4.Desktop Application.

  • Connect to the device.

  • Go to Tools > Firmware Update. The following popup will show.

Firmware update warning

Fig. 47 Firmware update warning

  • Click on Update, the following screen will be displayed.

Update inactive state

Fig. 48 Update disabled

  • Follow the on-screen instructions, then click ok. Once complete, screen will update as shown.

Updating Firmware

Fig. 49 Update ready

  • It should take around 2-3 minutes for the device to update firmware.

  • Once the update is complete, a pop up screen should come up. Press the reset button as instructed.

Log4.USB update ready state

Fig. 50 Upload success message

  • Click on OK to complete update.

Binary Log Conversion

The Log4.Desktop software is also used to convert binary logs to CSV files. The tool is accessed via the Tools > Log Conversion menu. The length of the CSV files is given by the length chosen in Tools > App Settings > Max Rows in a CSV File.

Binary log conversion tool

Fig. 51 Binary log conversion tool

  • Clicking the plus icon will open selection for .log4bin binary files saved on the SD card or on your computer.

Selection made in conversion tool

Fig. 52 Selection made in conversion tool

  • The edit menu allows for filename, firmware version, and device model to be selected. Once ‘save’ is clicked, the file will be renamed to reflect the parameters in the edit menu. Note: After renaming, the new filename may not update in the app. If this occurs, click the ‘X’ to remove the file from the list and then add it again by clicking on the plus icon.

Editing file details

Fig. 53 Editing file details

  • Output folder is selected by the output folder selection menu.

  • By clicking Convert, logs will be converted and saved into the output folder. Depending on file sizes and the number of files, this may take some time.

Completed conversion

Fig. 54 Completed conversion