Measure power through nRF PPK2 after changing txpower

[Md Mazedul Islam Khan]

 I am having trouble measuring the power through nRF PPK2 after changing the Thread txpower using the source meter mode. The issue is that when I set the nRF52840_DK txpower using `ot txpower 8`, turn off the device, set the PPK2 as the power source, and turn the device back, the txpower value changes to 0.

It is worth to note that I am using OpenThread CLI command `ot txpower` to set the txpower value.

How do I keep the txpower set even after I restart the device?

[dejans]

Hi,

Which NCS version do you use? Which NCS sample do you use?

Best regards,
Dejan

[Md Mazedul Islam Khan]

I am using NCS v2.2.0 and using Thread: CoAP Client and Thread: CoAP Server samples.

[dejans]

Hi,

You could set Tx power with otPlatRadioSetTransmitPower().

Additionally, you could have a look at this pull request and this commit which added default Tx power setting.

Best regards,
Dejan

[Md Mazedul Islam Khan]

Thanks for pointing it out. Does that mean I can simply use `CONFIG_OPENTHREAD_DEFAULT_TX_POWER` to `prj.conf` file and no need to use `otPlatRadioSetTransmitPower()` function programatically? If so, why the `CONFIG_OPENTHREAD_DEFAULT_TX_POWER` isn't appearing when searching on Kconfig reference list?

[dejans]

Hi,

I can see that CONFIG_OPENTHREAD_DEFAULT_TX_POWER is not defined in the Kconfig reference list for NCS v2.2.0, but it is defined for the latest NCS. You could try to checkout main. If this doesn't work for you, please use manual modifications of the source files specified in this commit.

Best regards,
Dejan

[Md Mazedul Islam Khan]

Unfortunately, using nRF SDK v2.2.99-dev3 didn't do it. So, I had to manually implement the commit by editing the source directly which isn't the standard way to do it but it will do the job for now.

I look forward to have the official release for it. Any idea in which version it will include and when that will available for everyone?