gnss-ui

GTK4 / Python based GNSS dashboard to display information gathered from GNSS receivers. The application includes a simple GPSD client that is capable of requesting NMEA and JSON data from a GPSD instance.

NOTE: This application is work in progress and possibly unstable, so things may break!

The UI allows displaying various information, such as:

• current position and gps quality
• current satellites in view and available
• positions of the satellites in a graphical view
• a map with the current position

In addition, the application allows recording GNSS tracks and exporting to GPX files.

Some screenshots:

Installation

Several methods are possible to use or install the gnss-ui:

1. git: just clone the repo and start gnss-ui.py in the src subdirectory.
2. arch linux: a separate project to build an arch linux package exists at https://github.com/mr-ingenious/gnss-ui-pkg. Please find further explanations there.

If time permits, maybe packaging for other linux distributions will be added.

Some python libraries are required (versions I currently use in brackets):

• GTK4 (version 4.14.4)
• PyGOBject (version 3.48.2)
• Cairo (version 1.26.0)
• libshumate (https://gitlab.gnome.org/GNOME/libshumate) (version 1.2.2)

Configuration

Application

The application is configurable via the appconfig.json file located at ~/.config/gnss-ui. The file is created automatically at first startup. Changes are effective after application restart.

Example (default settings):

{
    "created": "2024-07-11 22:14:18",
    "last_update": "2024-07-11 22:14:18",
    "config": {
        "general": {
            "panel_refresh_cycle_sec": 2,
            "resolution": {
                "height": 800,
                "width": 1200
            }
        },
        "ttyc": {
            "ttyname": "/dev/ttyUSB1",
            "baudrate": 9600
        },
        "gpsd": {
            "hostname": "localhost",
            "port": 2947
        },
        "startup": {
            "connect_to_gpsd": true,
            "panels_shown": [
                "map",
                "satellites_list"
            ]
        },
        "map_panel": {
            "auto_center": true,
            "initial_zoom_level": 5,
            "show_satellites_dashboard": true,
            "show_position_dashboard": true,
            "show_compass_dashboard": true,
            "start_latitude": 0.0,
            "start_longitude": 0.0
        },
        "recording": {
            "export": {
                "directory": "~/.gnss-ui"
            }
        }
    }
}

Description of the configuration options:

Configuration group	Description
general	Configuration of the default resolution of the UI and the refresh cycle of the panels
ttyc	Serial connection settings, if modem or GNSS receiver output (NMEA0183 format) shall be used directly
gpsd	Connection settings for use of gpsd. The gpsd JSON output format will be used
startup	Settings for startup, e.g., whether a connection to gpsd or serial connection shall be automatically established, or which panels are visible (possible values: "position", "satellites_list", "satellites_radar", "map", "compass", "recorder")
map_panel	Various settings for the map panel, such as start position of the map (default: 0,0), the zoom level or visibility of different dashboards within the map panel
recording	Recording specific settings, such as the export directory

Logging configuration

Logging can be configured with a log.ini file: ~/.config/gnss-ui/log.ini. As default, no log configuration file is created automatically, but the default logging is active (i.e., the application logs to ~/.gnss-ui/gnss-ui.log)

Example log.ini:

[loggers]
keys=root,app,datamodel,gpsd,ttyc,config,recorder,preferences

[handlers]
keys=consoleHandler,fileHandler

[formatters]
keys=fileFormatter,consoleFormatter

[logger_root]
level=DEBUG
handlers=consoleHandler

[logger_app]
level=INFO
handlers=consoleHandler,fileHandler
qualname=app
propagate=0

[logger_preferences]
level=DEBUG
handlers=consoleHandler,fileHandler
qualname=preferences
propagate=0

[logger_datamodel]
level=INFO
handlers=consoleHandler,fileHandler
qualname=datamodel
propagate=0

[logger_gpsd]
level=INFO
handlers=consoleHandler,fileHandler
qualname=gpsd
propagate=0

[logger_ttyc]
level=INFO
handlers=consoleHandler,fileHandler
qualname=ttyc
propagate=0

[logger_config]
level=INFO
handlers=consoleHandler,fileHandler
qualname=config
propagate=0

[logger_recorder]
level=DEBUG
handlers=consoleHandler,fileHandler
qualname=recorder
propagate=0

[handler_consoleHandler]
class=StreamHandler
level=DEBUG
formatter=consoleFormatter
args=(sys.stdout,)

[handler_fileHandler]
class=FileHandler
level=INFO
formatter=fileFormatter
args=('gnss-ui.log',)

[formatter_fileFormatter]
format=[%(asctime)s] [%(name)s] [%(levelname)s] %(message)s
datefmt=

[formatter_consoleFormatter]
format=[%(asctime)s] [%(name)s] [%(levelname)s] %(message)s
datefmt=

Usage

To make use of gpsd (see https://gpsd.gitlab.io/gpsd/ ) the daemon must be running in the background, but can also be started manually, e.g. for testing: gpsd -nND5 /dev/ttyUSB1. Refer to gpsd settings in the appconfig.json.

Another possibility is to use the GNSS output from the modem / GNSS receiver directly (e.g., /dev/ttyUSB1) - see ttyc settings in the appconfig.json.

Working directory

The application creates its files in ~/.gnss-ui. Such files are

• the SQLite database storing the recorded GNSS position information, satellites information etc.
• the default output directory for recording exports.
• the application log file

Further information

The application has been tested on a notebook with an integrated Quectel EM-05G modem, connected to gpsd and also via a direct connection to the serial GNSS output of the modem.

Compatibility with other modems or GNSS receivers is not guaranteed.