Can't figure out how to get Analog In (ADS1115) working

I’m running Arduplane 4.1 on Raspberry Pi(obal board). I have an ADS1115 converter on I2c with a voltage divider connected to channel 1. However, I have no idea how to enable it. In battery monitor there is Analog input, but then in HW version there is no ADS1115 to select.

Can someone help, please?

Well, actually it does work after a restart…

For others finding this thread. Here are my settings in mission planner battery monitor 1 page. From the top.

  • Analog voltage only
    -greyed out
    -0

It seems to expect voltage on channel 1 (not 0) of the board.

Anyone using this please make sure you use a voltage divider as the ADC shouldn’t be fed over 5v. I’m using a voltage divider with two resistors. 82k and 47k.

beware when running the ADS1115 from 3.3v the absolute maximum analog input voltage is VDD + 0.3v. To avoid damage to the chip, do not attempt to measure voltages greater than VDD.

Thanks. I’m powering it with +5V.

However, the voltage measurement is really off that is not possible to compensate with just a multiplier.

Specifically, if I set the multiplier to be correct when measuring let’s say 11V it will measure 0.2V over at 12V and 0.2V under at 10V. When I set it to measure spot on at 9V it continues to add extra 0.2V of error per 1V so 12. 0V measures as 12.6V.

I don’t suppose I can do anything else with the hardware as I’m using a simple voltage divider with 2 resistors (47k and 82k so no chance of heating messing up the measurements).

Is there anything I can set to subtract that 0.2V per volt in software?

Please check this topic It will help you.
https://github.com/HefnySco/OBAL/discussions/11#discussioncomment-2733657