HDS-9 and LINK-8 Interface

Electrical and electronic topics for small boats
jimh
Posts: 11711
Joined: Fri Oct 09, 2015 12:25 pm
Location: Michigan, Lower Peninsula
Contact:

HDS-9 and LINK-8 Interface

Postby jimh » Sat Oct 01, 2016 1:56 pm

In another forum on another topic, the subject of interfacing a Lowrance HDS-9 chart plotter and a Lowrance LINK-8 VHF Marine Band radio was introduced:

Ridge Runner wrote:I am interested in the integration of the HDS - 9 and Link-8 over the NMEA network. The Link-8 is a Class D DSC fixed mount VHF transceiver with a dual-channel AIS receiver and AIS plot functionality, so I should get very good integrated features.


The best method of making a digital data connection between a Lowrance HDS and a Lowrance LINK-8 radio is by using NMEA-2000. With NMEA-2000 network connections, the two devices will be able to exchange all the data they need. It is possible to interconnect to the LINK-8 using NMEA-0183, but the provisions of the LINK-8 require that two separate NMEA-0183 interfaces be used, as the digital selective calling (DSC) data and the automatic identification system (AIS) data are transmitted on separate circuits.

With an HDS-9 there is only one NMEA-0183 interface, and if connecting a LINK-8 radio one would have to choose to connect one of the two sources, that is, either DSC data or AIS data. You could not get both. I describe this limitation in much more detail in an earlier article on the LINK-8. See

http://continuouswave.com/ubb/Forum6/HTML/003590.html

For those reasons, NMEA-2000 is a better choice for connecting the HDS-9 to the LINK-8.