I have an Icom 604 with GPS capacity (NMEA IN port), but my GPS antenna connects into the interface of a complete B&G H1000 system, complete with CND chartplotter unit.
How do I get a GPS signal to the VHF? How do I get DSC information from the VHF back to the chartplotter?
With the Icom 604 it's normally done using NMEA 0183, but I don't know if your system has the output. Information is lacking as the H1000 system is discontinued but there did used to be a NMEA interface:
http://www.bandg.com/en-GB/Products/H1000-NMEA-Interfac---EN-DISCONTINUED/
It seems possible to get GPS info to the radio but I doubt that your CND would know what to do with DSC info.
in theory CND has NMEA Out port, it's used for send GPS to Instrument
If port not used - You can use it (but need make connector or have cable)
If port already used - look what instrument, some of them could have NMEA Out also
Or You can find NMEA duplicator - and split GPS before H1000