User`s guide

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Position Configuration
The Configuration – Position page has GPS sub-menu item.
GPS
Configuration – Position > GPS
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)
Checking this checkbox causes the NMEA sentence containing the number of active satellites
used to calculate the position, to be output.
Satellites in view (GSV)
Checking this checkbox causes the NMEA sentence containing the number of satellites in
view to be output.
Position and Time (RMC)
Checking this checkbox causes the NMEA sentence containing the current position and time,
to be output.
Course over Ground (VTG)
Checking this checkbox causes the NMEA sentence containing the course data to be output.
UTC and local date/time data (ZDA)
Checking this checkbox causes the NMEA sentence containing the current local time and
date, to be output.