Battery percentage measurement in nrf connect SDK

[Pranathi CH]

Hi Nordic,

I am exploring on how to use an ADC module for measuring the battery percentage for my nrf52840. I am working on the nrf connect SDK. Can anyone suggest me a sample for reading the battery percentage in the zephyr SDK?

Thanks,

Pranathi

[Sigurd Hellesvik]

Hi,

See Battery Voltage Measurement sample

Regards,
Sigurd Hellesvik

[Pranathi CH]

Hi Sigurd,

I can see the board compatibilities for the battery sample is only for partical_xenon and thingy52_nrf52832 but I only have nrf 52833 dk with me right now, So I tried to build with that configurations and faced errors..

Can you suggest me any sample that could be built for ntf52833 dk?

Thanks,

Pranathi

[Sigurd Hellesvik]

Board compabilites for samples indicate what samples are tested for, not what they will work for.

Likely, you will have to reconfigure the sample for it to work with the boards you need it to work for.

I recommend the Nordic Developer Academy as an excellent place to start learning the nRF Connect SDK.

Regards,
Sigurd Hellesvik

[Pranathi CH]

Hi Sigurd,

I did change the build configuration for the battery sample with nrf52833dk_nrf52833 and I got the build errors as such:

• '__device_dts_ord_DT_N_S_zephyr_user_P_io_channels_IDX_0_PH_ORD' undeclared here (not in a function)
• 'DT_N_S_zephyr_user_P_io_channels_IDX_0_VAL_input' undeclared here (not in a function)
• identifier "DT_N_S_zephyr_user_P_io_channels_IDX_0_VAL_input" is undefined
• identifier "__device_dts_ord_DT_N_S_zephyr_user_P_io_channels_IDX_0_PH_ORD" is undefined

Thanks,

Pranathi

[Sigurd Hellesvik]

Which changes did you make to the sample?

[Pranathi CH]

I changed the build configuration for nrf52833 as the compatible build for it is partical_xenon and thingy52_nrf52832, I did not get any errors while building the battery sample for these two but I faced issues when I build the project with nrf52833dk_nrf52833 build configuration.

[Sigurd Hellesvik]

Have you added a vbatt node with voltage-divider as described in the sample documentation, and have you specified the A0 pin there? See Battery Voltage Measurement sample documentation for details.

[Pranathi CH]

Yeah I have added the vabtt node in by dts file and still getting errors and how & where do I specify the A0 pin I could not find about it in the link?

Sigurd Hellesvik said:

Battery Voltage Measurement sample documentation

[Sigurd Hellesvik]

From the docs, I added this to the sample as an overlay:

/ {
   vbatt {
      compatible = "voltage-divider";
      io-channels = <&adc 4>;
      output-ohms = <180000>;
      full-ohms = <(1500000 + 180000)>;
      power-gpios = <&gpio0 4 0>;
   };
   zephyr,user {
      io-channels = <&adc 4>;
   };
};

Our nRF52840DK does not have a voltage divider to measure the power, so you will have to add this yourself and configure the overlay accordingly