Gps Parameters - Digi TransPort User Manual

Positions

GPS parameters

One of the options available on some models is the ability to connect a GPS receiver which
enables the router access to geographical position information. The module may be internal or
external. In either situation, an internal asynchronous serial (ASY) port will be used for the
connection. The standard way that GPS modules send the data is using National Marine
Electronics Association (NMEA) standard 0183 messages. This protocol is usually simply referred
to as NMEA. Routers offering this functionality support the most common NMEA data messages.
These will be described below. GPS receiver modules normally accept configuration commands
which specify which of the NMEA messages should be sent to the requesting host. The following
descriptions show how to configure a router to accept and forward GPS data using the web
interface and by using CLI commands.
Enable local monitoring
When checked, this checkbox allows messages from the GPS receiver may be viewed on the
Management – Position > GPS status page. Which messages are displayed is configured via
entries in a table.
GPS Module Initialization String
Some GPS receivers may require configuration via an initialization message at start-up in
order to send the appropriate messages in the required format, at the required data rate. Any
such required command string is entered into the text entry box and will be sent to the
attached GPS receiver module when the router initialises the module.
The table described here controls which NMEA messages should be sent from the module.
The default is to enable all messages.
Fix data (GGA)
When the associated checkbox is checked the fix data (2D, 3D or no fix) will be output.
Position (GLL)
This checkbox, when checked, causes the Geographic position (Latitude/Longitude) sentence
to be output.
Active Satellites (GSA)
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