networks appear to use a reasonably standard version of Ethernet at the
physical level, but they send proprietary messages among their devices
connected to it. Certain of the variants simply seem to involve using
more watertight plugs than the standard. That can mean that multiple
vendors' products can coexist on the same physical network, which
does simplify installation and maintenance. On that network, however, a
Brand X device may be able to communicate with other Brand X devices,
while Brand Y devices can only talk to other Brand Y devices.
Not supported other than among the devices of a single vendor...support being a flexible concept
Some radar systems and other
graphics-intensive systems may use a standard video interface such as
the television NTSC or PAL standards, or one of the computer monitor
VGA family. If the radar processor expects to interact with the display
to create images, rather than send the display a predefined image, it
is unlikely there will be any interoperability between vendors.
Any specific interoperation
request is apt to need testing to see if it is feasible, which it may
be, either directly or with simple conversion devices. Beachwerks
cannot guarantee that it can make Brand X talk to Brand Y, but we have
the skills to see if full, or partial solutions, make sense. Common
cabling systems are examples of useful partial solutions.
Appears to be 100BaseTX and compatible with industry switches. It
distributes video signals with either television formats such as NTSC
or PAL, or computer formats ogf the VGA family.
Furuno's NavNet, described as proprietary, appears to be Ethernet at
the physical and data link levels, which can let it be used within a
common cabling system. Furuno is offering upgrade paths to the latest
NavNet 3 technology. NavNet 3 includes NMEA 2000 technology, but
Furuno may be positioning its multifunction displays (MFD) as the
center to which existing components connect, rather than being
something that can talk to non-Furuno devices.
Their strategy seems flexible, however, with such products as the FAX30
device, which connects to a PC with Ethernet and makes it a
Navtex and Weatherfax receiver. The FAX30 does not seem to need
software beyond a familiar web browser. Furuno 8 and 12-inch NavNet
displays, which are intelligent, can receive graphic information via
Raymarine uses several different networking technologies. Some are variants on industry standards, while others are unique.
SeaTalk is the oldest, and is a
daisy-chained, electrically unbalanced signal. This appears to have no
compatibility with any industry standard, and, indeed, SeaTalk
instruments of different vintages use different plugs.
In contrast to SeaTalk, SeaTalk 2
is based on the NMEA standard, but uses a different connector and is
not completely compatible at the level of messages exchanged. SeaTalk 2
can be interfaced to, or made compatible with, SeaTalk, NMEA 0183, NMEA
2000 and USB 2.0.
Again, Raymarine defines a network as a
variant of a standard protocol, Ethernet, at the physical level.
SeaTalk HS connectors do have an advantage over standard Ethernet
cables, in that the plug has additional sealing for water resistance.
The "HS" is for "high speed", making it fast enough to transmit
rapidly changing graphic information such as radar displays. Sea
Talk and Sea Talk 2 do not support such graphics.
HSB and HSB2
HSB is Raymarine's technology for
interconnecting high-performance graphic displays such as radar screens
and chartplotters. Not all Raymarine devices can be interconnected. If
two devices are "Plus" products, they use HSB2 and will interoperate.
If neither one is Plus, they will interoperate as HSB. Plus and
non-Plus units, however, do not appear to be interoperable with
Raymarine technology. Raymarine does have an an interface to bring HSB2
displays into a PC. If the PC runs a compatible chartplotter, which
emulates the Raymarine E-series, you get a radar overlay on a PC, which
can be running more open applications.
Raymarine has not given any public description of the interface between
the radar antenna and display. This interface is closed and proprietary
for most vendors.
SeaTalk NG (Next
Generation) is NMEA
2000 compatible system, although it is not itself NMEA 2000 certified.
Raymarine offers adapters for NMEA-2000 conformant networks, as well as
SeaTalk and SeaTalk 2. NG networks, like NMEA 2000 but not
Ethernet, is architected around a backbone cable with drops to specific
devices. While low-current devices will be able to be powered from
SeaTalk NG, it is unclear if multi-ampere feeds will be available.
The SmartCraft networking technology from Brunswitch Corporation is
similar to NMEA 2000, and indeed draws from the automotive Controller
Area Networks (CAN) that inspire NMEA 2000. Since Brunswick is
heavily involved in engine technology, the CAN emphasis is not
surprising, as well as the prioritization, within the network, of
engine information. SmartCraft networking, however, is not an open
standard, although Brunswick does have a cooperative program to allow
other manufacturers, presumably under license, to connect to the