Using CayenneLPP with a sensor that outputs multiple readings

1

Hello,
I have a device, that has multiple sensors.
Each sensor outputs multiple readings. (this is the issue) CayenneLPP works great if each of your
devices outputs only 1 reading using the channels, however. I would like to group multiple device readings together so I can more logically identify them in the output data.
An example of this is:

lpp.addLuminosity(1, uv.readVisible());
lpp.addLuminosity(2, uv.readUV());

Where these 2 readings can be sent on channels 1 and 2, however, there is nothing showing they are from the one sensor. What would be great is if I could have a sensor flag such as

lpp.addLuminosity(1, 1, uv.readVisible());
lpp.addLuminosity(1, 2, uv.readUV());

lpp.addLuminosity(2, 1, uv.readVisible());
lpp.addLuminosity(2, 2, uv.readUV());

Has anyone found a way around this limitation with CayenneLPP? Or does anyone know of a good alternative?

I was at first hoping to use CayenneLPP as it seems to have community support, but if this is a limitation that cannot be overcome, I hope to find an efficient alternative. Possibly I may have to modify the Cayenne lib myself… (i hope not)

Thank you very much!
-Kevin

2

What is the destination for your data? ie, does the end point support CayenneLPP or does it only support CayenneLPP.

Overall, I can see it’s utility as a quick win if the data is being ingested by Cayenne but it does auto-expand your payload and there are approximately one billion missing formats for all sorts of sensors.

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The endpoint is a Node.JS endpoint that I wrote, so it can support whatever I want it to.
I should also mention that I have designed my device so I can add/remove sensors on the fly, and that is why I need to have the ability to see what data is coming from what sensor specifically.

The sensors are all ModBus, so I am using the ModBus Address to ID each sensor.

Do you know of any pre-made alternative? If not, I may have to get to work and try to work something out myself. I am just really hoping that this is a wheel that has already been created.

4

Possible solution:

Use the channel as two nibbles, first nibble is the device (limited to 0-15 so 16 values) and the second nibble as channel within the device (max 15 channels so fails if you have > 15 sensors per device).

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