start
back overview next

Settings

GPS

Here you can enter connection information regarding your GPS receiver. Select the correct device and baud rate, if necessary, for your GPS. Please refer to your GPS manual for these values.

Cumulus can provide you some status information concerning your GPS reception. If you want to know what satellites are in view, where they are, how strong their signal is, or if you want to take a look at the raw NMEA stream of your GPS, use the G key or click on the GPS status indicator in the status bar. This will open a status dialog for the GPS. The dialog can be closed with the Escape key.

Note that Cumulus will only accept GPS data sentences with a valid checksum. It is also able to process the proprietary sentences emitted by a Cambridge, Volkslogger or LX device and to process this these data. Wind, variometer and MacCready data from such devices will be taken over automatically, if they are available. MSL and STD altitude, derived from the pressure sonde are only taken on demand.

GPS Device
In the combo box you can select the device to be used for your GPS connection. There are the following devices available:

Serial and Bluetooth devices need also a speed rate for their operation. The default serial NMEA connection speed is 4800 bps for Bluetooth we recommend to use 115200 bps.

If you use a Nokia Internet Tablet N800/N810 the entry GPS Daemon should be your first selection. Unless you want to connect via your USB interface adapter to the GPS. In such a case select the device /dev/ttyUSB0.

If your device is not contained in the selection list, you can change one of the predefined entries to your need. This is unsupported on the Nokia Internet Tablet.
Altitude Reference
Most of the GPS devices send MSL (mean sea level) altitudes but some send HAE (Height above ellipsoid.) If your displayed altitude deviate always by a constant factor, try the other setting for your GPS. If that will not help, you can select the Altitude User mode and add an own altitude correction in the spin box below.

Special Options
Some gps devices can be initialized by saved position data to find a satellite signal more quickly. To enable this check Soft start. If this does not work, a Hard start can be forced when Cumulus starts up. If there are still problems to get the device working, a Reset to factory settings can be initiated by pressing the button.
Update system clock
Cumulus is able to synchronize the PDA system clock to the GPS time, if the option Update system clock is activated. But this will only work, if cumulus is running as user root. On Nokia Internet tablet this feature is switched off.

Processed GPS sentences

Cumulus processes the following NMEA and proprietary sentences:

$GPRMC Recommended Minimum Specific GNSS Data
$GPGLL Geographic Position - Latitude and Longitude
$GPGGA Global Positioning System Fixed Data
$GPGSA GNSS DOP and Active Satellites
$GPGSV GNSS Satellites in View
$GPDTM Map datum
$PGRMZ Garmin proprietary sentence with altitude information
$PCAID Cambridge proprietary sentence with STD altitude
!w Cambridge proprietary sentence with MSL altitude, QHN setting, wind direction, MacCready, wind speed and variometer
$PGCS Volkslogger proprietary sentence with STD altitude
$LXWP0 LX Navigation proprietary sentence with MSL altitude, variometer and wind data
$LXWP2 LX Navigation proprietary sentence with McCready data

start
back overview next