Multiple battery voltages as telemetry

[ZZ-Cat]

Discussed in #173

^{Originally posted by CarlouT January 21, 2026}
Fist of all, I would like to thank all the developers of CRSFforArdino. I have implemented the telemetry example which is working great. My question is, is it possible to send 3 sets of batteries? Here's my use case:

I fly petrol planes which usually has 2/3 batteries. One/two for the receiver and another one for the ignition. I wold like to send individual telemetry battery voltages back to the radio so that I can set an alarm before any battery gets totally drained and may casue a crash. Is this supported by CRSFforArduino. If yes, can samebody provide an example?. Thanks in advance.

Is it also possible to send RPM and temperature back to the radio?

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As per the discussion above, and with the voltage group field in CRSF's telemetry, it's possible to transmit multiple battery/cell voltages as telemetry. So I have derived an issue here so that it's triaged and on my to-do list.

[CarlouT]

Thanks for adding this in your T-Do-List.

Update on my Prototype - I am now able to read GPS data from the GPS module BN880. GPS values are now sent to the radio. There is small issue on the the speed and altitude values. It looks like when the GPS speed and altitide is sent to the radio, there is a conversion hapening somewhere. But I was able to work around it by:

  float altitude = gps.altitude.meters() * 100;
  float speed = gps.speed.kmph() * 27.77777777777;

I'm happy to keep it like this for now.

Next in line is to code the BMP 280 barometer module

[CarlouT]

Would it be possble for me to request an enhancement to add Temperature and RPM telemetry?

[ZZ-Cat]

Would it be possble for me to request an enhancement to add Temperature and RPM telemetry?

Yea, you can submit that as a separate Issue.
In my Issues tab, click New Issue -> Feature Request and fill out the form, and go from there.