- I expect you have DC-DC converter on your board and you remembered to cut link between VUSB and Vin on Teensy.
Yes, I have a 12v > 5v DC-DC converter onboard and cut the link.
- Also hopefully ECU or some system will send trim data to NMEA2000
The VesselView Link takes the ECU data and puts it on the NMEA2000 network -- this is all functioning already on my Lowrance MFD.
- DataDisplay is a bit old and does not seem have automatic library selection for board. DataDisplay2 seem to already have handling for EngineRapid (PGN 127488). On that you will need only comment unnecessary handlers on handler list NMEA2000Handlers. Or maybe you already rewrite datadisplay to match your needs?
Got it -- I meant to say DataDisplay2 example. I see these handlers in the demo -- are they all good?
// Do not forward bus messages at all
// Set false below, if you do not want to see messages parsed to HEX withing library
Your gauge looks very nice and could be used to display different data. With single scroll button besides gauge one select data from NMEA2000 bus - not just trim.
That's the plan -- right now I have two screens ready (Trim and Fuel). I will add more screens I can cycle through to make it a quick-look MFD.
And if you want to see your new gauge on NMEA2000 device list, you have to add device definition commands to setup as e.g. in TemperatureMonitor example. You should then use Class code 120 (Display) and Function code 130 (Display). In principle in NMEA 2000 listen only devices are not allowed. On reason is that each device, which is taking power from bus, should inform it so that total power can be calculated. Just on your own boat this does not matter, if you just remember to keep used power low enough. There are also other things to concern, if you start to change you device more "NMEA2000 certified".
Good idea! I'll add that code so the device shows up -- the power usage is pretty low overall. The Teensy & Display plus the MCP2551 is all that is being used. Initial measurement looked like about 90mA being pulled from the 12v input side.
Thanks again timolappalainen!