Fig.: GPSmap 420 with CANet (Garmin)
CANet was developed by Garmin for marine devices. It uses the CAN bus at the lowest physical level, but uses different implementations at higher levels of CAN and is not compatible with NMEA2000. Like C-Net 2000, CANet is a proprietary protocol that only works with Garmin devices. Many older Garmin plotters were equipped with CANet and NMEA0183. To a small extent, data could also be exchanged between CANet and NMEA0183, such as speed and depth data. Unlike the competition, CANet does not use any special connector technology and relies on screw terminals, which makes installation significantly easier and cheaper. CANet was used specifically for sensors and for data exchange between Garmin display devices. In addition to CANet, the same devices were also offered with NMEA2000, which could be used much more flexibly with devices from other manufacturers. However, the colorful sonar data carpets from Garmin Sounder and Loggen could only be transmitted with CANet. CANet is no longer relevant in today's on-board networks and can only be found in old installations. There is no future viability. NMEA2000 would be a better alternative.
CANET is a name-similar implementation for CAN in Ethernet environments for industrial applications, which is not compatible with Garmin's CANet and should not be confused with it.
open-source
There is no separate open source implementation for CANet, since CANet is a very specialized protocol from Garmin.