Diagrams  Brookhouse standard model multiplexer connections

The diagrams below show examples of possible multiplexer configurations, standard model only..

Please note that although  all diagrams show a (laptop) computer, there are many applications without  computer.  For example, a standard multiplexer can be used for combining GPS and wind instrument data to a single NMEA data stream  as input for an auto pilot. 

Diagram 1

This diagram shows a simple configuration with individual NMEA talkers. All instrument data is combined to a single data stream to feed a navigation program on a (laptop) computer and/or one or more NMEA listeners (auto pilot, DSC radio, repeater instrument, chartplotter) via the NMEA out port (RS422). In addition to the 4 NMEA input ports, the multiplexer has a 5th input port that can be used either to enter computer output data in the multiplexer or for the connection of an extra data source. The multiplexer baudrate setting can be 4800, 9600, 19200 or 38400,  unless standard NMEA listeners are connected to the multiplexer output port, that only support 4800 bps.

Diagram  2

As diagram 1, but here the  instruments are inter-connected in a network with a common NMEA 0183 output.

Diagram 3

In this configuration, the multiplexer has  the optional Seatalk conversion option installed. The multiplexer converts Raymarine Seatalk data to NMEA 0183. The converted data  from all Seatalk instruments (incl Seatalk GPS if present) is placed in the combined data stream as if it originates from NMEA 0183 instruments. If the Seatalk option has been installed and activated, input # 1 cannot be used for NMEA. If Seatalk is disabled in the multiplexer setup menu, port 1 can be used for NMEA input.

Diagram 4

As diagram 2, but in addition an auto pilot is connected to the NMEA out port of the multiplexer. The navigation software is set up to control the auto-pilot for steering to a waypoint or along a route. The 5th multiplexer input port is used for computer output (RS232 or USB).  In this case the multiplexer output baudrate setting has to be 4800, because this is the only baudrate the auto pilot supports.  The NMEA output of the auto pilot is heading data from the fluxgate compass  that enters the multiplexer via input ch4.

Diagram 5

Another configuration with Seatalk instruments. The Seatalk auto pilot is controlled by the navigation software.  The auto pilot NMEA out port does not need to be connected to the multiplexer because heading is already available via Seatalk.

 

 

Diagram 6

An all-NMEA 0183 configuration with multiple NMEA listeners receiving data from the multiplexer via NMEA out.

 

Some more examples:

 

 

Standard NMEA multiplexer Diagram 1

 

The system shown here is a simple system with GPS and instruments from different manufacturers, all with NMEA output, no computer. NMEA data from 4 “talkers” is combined by the multiplexer and transmitted to the Auto Pilot and a repeater instrument.

The Auto Pilot can now be used in GPS-mode (track-mode) to steer to a waypoint or along a route. In “wind mode” it can steer the vessel at a fixed angle to the wind, using the wind data received from the wind instrument. Speed data from the GPS and speed/log instrument improve the performance of the Auto Pilot

 

The repeater can display any data from the instruments or GPS.

 

 

 

Standard NMEA multiplexer Diagram 2

 

This diagram shows a system with the same functionality as in diagram 1, but here the instruments are Raymarine, interconnected via the Raymarine proprietry Seatalk protocol.

 

The multiplexer is the standard model with Seatalk option. The instrument data is translated to NMEA by the multiplexer. In this diagram no Seatalk GPS is shown, but the mux can also translate Seatalk GPS data. As the Seatalk instruments occupy only one port on the multiplexer, 2 NMEA input ports are still available for the connection of other NMEA “talkers”.

 

The Auto Pilot can be used in GPS-mode (track-mode) to steer to a waypoint or along a route. In “wind mode” it can steer the vessel at a fixed angle to the wind, using the wind data received from the Seatalk wind instrument. Speed data from the GPS and speed/log instrument improve the performance of the Auto Pilot.

 

The NMEA repeater can display any data from the instruments or GPS.