How to send more than one battery back to the receiver

[CarlouT]

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?

[ZZ-Cat]

You're welcome. It's mainly me, plus my occasional contributors. =^/.^=

Anyway, CFA currently implements the Battery Sensor field, as seen in the telemetry example.

A possible solution here would be to implement the Voltage Group field, where you'd be able to assign an arbitrary number of multiple voltage sources. It looks like I could expand the battery sensor telemetry function to maybe include multiple instances or something. 🤷🏼‍♀️

[CarlouT]

Thanks for your quick reply. I've read about the Voltage Grop concept but I don't know how to code it in the sketch. Would it be possible for you to add an example?

[ZZ-Cat]

It'll be a bit of time before I do add it, as my current focus is with refactoring CFA. So, it can be done, but not right away.
I can derive an Issue from your OP, so that it least gets it triaged and in my todo list so that I don't forget about it =</.>=

Update: I got it in the pipeline, created as #174 and I marked it as triaged.

[CarlouT]

That would be fantastic. No rush, I will wait. Hoping to see the RPM and Temperature as well. Here's my current prototype. Once all the sensors are working, I will try to design the PCB in EasyEDA and order it. My vision is to have the following:

1. Battery telemetry - 3 batteries via voltage dividers
2. Vario using BMP280 - In the club I am flying, we have a ceiling of 400 feet so i will set an alarm to tell me if I go beyond this
3. GPS using BN-880
4. RPM - Signal coming from the Tachometer output of the ignition coil.
5. Temperature - to send the engine temperatre to the radio

[ZZ-Cat]

Oh dude, that's awesome! =^/,..,^=