barnaclebill - What is the maximum rate at whic...
What is the maximum rate at which "standard" PGNs (i.e. non-Rapid Update) can be sent on the network (assuming the network isn't congested. I have 2 transducers and one SK server on my network). 250 Kbps / 8 bytes per frame = 3906 frames per second...valid math?
5 Replies
8 bytes of data and 8 bytes of headers, so one half of that. You can probably get close to that number if you only have one active device.
.. just curious .
? what are you sending that needs such a fast update rate?
Nothing...just a discussion on another forum about whether N2K sensors are as good (in terms of resolution) as analog sensors. They posted a graph with a 1Hz update rate for wind speed, which obviously is going to sacrifice a lot of granularity. I've added some timers to my ESP32 code because I'm curious how frequently my transducers are transmitting.
Incidentally, I don't suppose any of our existing plugins report average transmit rate, packet size, etc...?
It’s an interesting discussion because it seems that there is a common rate for each PGN. But the MFD is really the determining factor for rate because they may not work if the rate is too slow or too fast.
Yeah, the NMEA 2000 standard defines transmission intervals for different PGNs. Canboat already has partial information on them. I don't think transmitting more often has any drawbacks, but transmitting too rarely might make MFDs invalidate the data between the PGNs, resulting e.g. in jerky gauges.