Advanced NMEA Data Logger

Grouping NMEA data from two data sources with different communication parameters


I have two data sources, depth sounder connected to COM4, 4800bps, 7 data bits, no parity, 1Hz, $DPDPT (with Aten USB), and GPS (Geomax Zenith20+Getac236) connected to COM3, 9600bps, 8 data bits, no parity, 1Hz, $GPGGA.

Now I want to redirect incoming data simultaneously, without stopping collecting data to navigation software, to my Advanced NMEA Data Logger in two columns, row by row.

Preliminary requirements:

  1. Advanced NMEA Data Logger Enterprise, or a trial version (download).
  2. Aggregator data filter plugin.
  3. Deadband data filter plugin (options).


Configuring data source for GPS

1. You need to create two configurations in the main window using the "Green Plus" button. One configuration will handle data from GPS, and the second configuration will process data from the depth sounder. You can open and edit the existing configuration at any moment using the following menu item: Options → Manage configurations → Your configuration → Modify.

2. Switch to the "COM port → COM port settings" tab (fig.1), then select COM ports in the list with COM ports.

COM port settings for GPS
Fig. 1: COM port settings for GPS

3. Switch to the "Modules → Query Parse Filter" tab (fig. 2).

The parser module
Fig. 2: The parser module

4. Click the "Setup" button next to the "NMEA data parser" item.

5. When a dialog box appears (fig. 3), select the GGA sentence from the list.

Selecting the GGA NMEA sentence
Fig. 3: Selecting NMEA sentences

6. On the "Common" tab (fig. 4), you can leave default settings as shown below.

NMEA sentences aggregation
Fig. 4: NMEA sentences aggregation

7. Save the changes by clicking the "OK" button.

Configuring data source for the depth sounder

8. Select the second configuration in Options → Manage configurations → Your configuration → Modify.

9. Repeat steps 2 - 7 for the depth sounder but select the DPT sentence in the parser (fig. 5).

DPT sentence
Fig. 5: DPT sentence

Configuring data aggregation

10. In the configuration for COM4 (sounder), select data redirection (fig. 6). So, the parsed data from the sounder will be passed to a configuration with GPS data and processed there.

Data redirection
Fig. 6: Data redirection

11. In the configuration for COM3 (GPS), select the "Aggregator" plugin (fig. 7). It can group data from different data sources into one data row.

Selecting the Aggregator plugin
Fig. 7: Selecting the Aggregator plugin

12. Select one variable from each data source in the "Aggregator" plugin settings (fig. 8). The plugin will combine data rows containing these variables and pass the grouped data to data export plugins. Source data rows will be ignored.

Configuring the Aggregator plugin
Fig. 8: Configuring the Aggregator plugin

Configuring other options

13. Open the configuration for COM3 and change data view mode in the main window and select the "CSV" format (fig. 9).

CSV data view mode
Fig. 9: CSV data view mode

14. Configure log files settings: change mode, a file name prefix and extension, and other important options, as shown in figure 10.

Log file settings
Fig. 10: Log file settings

15. Save the changes by clicking the "OK" button.

16. Wait for incoming data from both data sources. The CSV data string appears in the main window when the parser receives selected NMEA sentences from both data sources. Immediately, the logger writes the same string to a log file.

NMEA - CSV data
Fig. 11: NMEA - CSV data


My NMEA devices send data too often. How can I write to a CSV file once per minute?

  1. Open the configuration for COM3.
  2. Enable the "Deadband" filter plugin and place it below the "Aggregator" plugin
  3. Select one parser variable, select the filtering method, and specify the interval in seconds. For one minute, you should set 60 in position 3.

Deadband plugin settings
Fig. 12: Deadband plugin settings

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