ADDITIONAL SEATALK1 SETTINGS
These settings are very useful to overcome compatibility issues with some softwares that do not comply with generally agreed standards. You can set the following parameters:

• ST > NMEA0183 MODE: This drop box controls the conversion from SeaTalk datagrams to Nmea0183 messages. You can choose between options 0, 1, 2 or 3. Option 0 is the default option where only standard Nmea0183 messages converted from SeaTalk datagrams are transmitted. In Option 1 not only the datagrams that generate standard Nmea0183 messages are converted. These datagrams, normally related to autopilot operation, generate non standard Nmea0183 messages which are a transliteration of the datagram starting with the string $STALK. This allows applications to monitor and report Raymarine autopilot current status and other features that do not have standard Nmea0183 converted data. In Option 3 no conversion to the standard Nmea0183 messages is performed. Instead, every datagram will only generate the equivalent Nmea0183 $STALK message.
• SOG_to_STW: When set, the multiplexer will use the value of 'Speed On Ground' extracted from a Nmea0183 GPS message to generate datagram 20 (known as STW - Speed Through Water). This is useful if no Seatalk STW sensor is present. Note that this is internally disabled if either Seatalk datagram 20 or datagram 26 (which refer to speed over the water) are received from other sources, in order to prevent data clashes on the SeaTalk network.
• SAILGRIB_VHW: The Sailgrib application does not follow normal accepted practices and ignores some messages that only carry partial data. This results in an apparent data loss when it gets Nmea0183 messages of the type VHW (Water Speed and Heading) with an empty Heading field as it is the case when the multiplexer converts Seatalk water speed datagrams. Setting the SAILGRIB_VHW checkbox overcomes this by adding an existing heading if it is available (eg from an Autopilot).
• ST26_INV_IGNORE: It has been noted by some users that the high precision Seatalk26 STW datagram (datagram 26) can sometimes indicate that the data is INVALID even when observation suggests that the data is actually OK. Setting the ST26_INV_IGNORE check box will allow the multiplexer to convert datagram 26 to the corresponding Nmea0183 message even if the invalidity bit is set.

PAIRING MULTIPLEXERS
In order for 2 multiplexers to work together, they need to be paired. Pairing consists on providing the Mac Address of the multiplexer you want to communicate with. Each multiplexer has a unique Mac Address which is shown in the area below the logo image of the present webpage. Once you know the Mac Address of the other multiplexer you have to enter it in the text box referred to as PAIRED MULTIPLEXER. You need to enter the Mac Address in the exact format as shown. If you make a mistake when you type the Mac Address, an error message will be displayed in red and you will not be able to proceed until you enter a valid Mac Address. Pairing another multiplexer with the NMEA3WIFI can be thought as if an EXTRA input/output port is added to the NMEA3WIFI multiplexer. You can route data from any of the inputs of the NMEA3WIFI to that EXT output port which will be received (and routed) by the other multiplexer. In the same way, you can route the data received from the other multiplexer at the EXT input port and route it to any of the NMEA3WIFI outputs. The best way to test if 2 paired multiplexers are working as expected is to enter Simulation Mode in one of them and enter Debug Mode in the other one. The simulated data generated by one of the multiplexers should be shown on the Debug Window of the other multiplexer. There are 3 possibilities for the 2 multiplexers to talk to each other:

• Both multiplexers only create their APs and are set not to connect to any external network (router, home WiFi or smartphone hotspot).
• One multiplexer only creates its AP network and the other multiplexer also connects as a station to the AP created by the first multiplexer.
• Both multiplexers also connect to a SAME external network (router, home WiFi or smartphone hotspot).

There is no guaranty that the multiplexers can talk to each other if they also connect to DIFFERENT external networks (router, home WiFi or smartphone hotspot). Also note that the NMEA3WIFI multiplexer can talk to more than one multiplexer if you enter FF:FF:FF:FF:FF:FF as the pairing Mac Address. This address is understood as a broadcasting address and every multiplexer in range will receive the messages sent by the NMEA3WIFI. Finally note that if you are using the NMEA3WIFI alone, it is advisable to uncheck all the 5 >EXT as well as the 4 EXT> checkboxes.