Raymarine e7 User Reference page 305

Menu item
Bridge NMEA Heading
NMEA Output Settings
Customizing your display
Description
If set to ON, NMEA heading data will be bridged onto the SeaTalk
data bus, and will be sent to all NMEA-connected devices. If
set to OFF, NMEA heading data will NOT be bridged onto the
SeaTalk bus. An example of a use for this setting is when using
MARPA with an external fast heading sensor, in which case you
should set this option to OFF to ensure that all NMEA-connected
units receive heading data from the external heading sensor.
Allows you to enable or disable the individual NMEA "sentences"
that are sent by the multifunction display to any devices
connected the NMEA output port.
Options
• On
• Off (default)
• APB
• BWC
• BWR
• DBT
• DPT
• GGA
• GLL
• GSA
• GSV
• MTW
• MWV
• RMA
• RMB
• RMC
• RSD
• RTE
• TTM
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