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svalvasori asked

Changing NMEA2000 Instance Number on Cerbo GX

I've got a 4-20mA sensor in my holding tank connected to input 3 on the Tank 140, connected USB to the Cerbo GX. The Cerbo is connected to my SeatalkNG NMEA2000 network. It all works, but the instance number for Waste Tank assinged by the Cerbo is 9. I need to display this data on a Veratron gauge, which of course only supports instance 1 to 8.

I changed the instance number in the Cerbo to 1:

1658069788744.png

I also verified with the dbus commmand that the instance number is set to 1. I've rebooted the Cerbo and still, the waste tank instance is 9 on the network. It stays a 1 in the Cerbo display and CLI, but I can only see the values on instance 9, which I've verified on a Maretron DSM410 display.

Have i missed something? Or is this a bug?

cerbo gx
1658069788744.png (127.5 KiB)
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3 Answers
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svalvasori answered ·

I should add that my Cerbo firmware is 2.87.

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bathnm answered ·

Have you taken a look at this link regarding changing instance? I think the value of 9 is the data instance, what you are changing in the Venus GUI is the device instance. What instance value is the Maretron DSM410 display looking for?

I do not have any tank senders, so can not look at how it enumerates the data instance, and how to change it if possible within the VenusOS itself.

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svalvasori answered ·

@Bathnm Thank you! You pushed me in the right direction. I didn't understand the difference between a data instance and device instance. Using dbus-spy I changed the number to 0 and the Veratron is now happily displaying data.

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