How to have board-specific prf.conf files

[mkjones]

I developed a project using nRF Connect 2.6.1 in VSCode.  I created a custom board for the development board I was using (the SparkFun Pro nRF52840 Mini - Bluetooth Development Board https://www.sparkfun.com/products/15025).  Now the final board has been produced, and I have created a custom board description for it (the final board is different than the Sparkfun board, although they both use the same processor).

I would like to be able to build my code for either the development board or the final board, so I need to have a general prf.conf file which has settings that apply to BOTH boards, and then board-specific prf.conf files that contain settings specific to the particular board.

I cannot figure out how to accomplish this.  I only seem to be able to get it pull in prf.conf.  I have created a new build configuration for the new board; what is the magic for pulling in both prf.conf and a config file for the board selected?  What does the prj file need to be named, and where should it be located?  How should the build configuration be set up?

--mkj

[Amanda Hsieh]

Hi, 

When the configs are board-specific, you can place them in the boards folder, are named <board>.conf, and they are applied on top of the default Kconfig file for the specified board. Check out the Configuring Kconfig. 

You also could use CONF_FILE to pass extra configs. See The Initial Configuration doc. 

Regards,
Amanda H.

[mkjones]

I tried putting <board>.conf file in the boards directory, but it still only seemed to pick up the prj.conf (it did not appread to read in the board.conf file).

I'll try out the CONF_FILE setting (I set that in the build config, right?).

[Amanda Hsieh]

mkjones said:

I tried putting <board>.conf file in the boards directory, but it still only seemed to pick up the prj.conf (it did not appread to read in the board.conf file).

The <board> name should be the same as the board for the building. Could you provide the completed build log via toolbar -> insert -> code?

mkjones said:

(I set that in the build config, right?)

Yes, with "-DCONF_FILE=YourExtraConfig.conf".

[mkjones]

My <board>.cong file was in the boards directory, and had the same name as the board.  It does not get loaded automatically.

I was able to get it to load my modifying the CACHED_CONF_FILE build settings and adding the board.conf after the prj.conf.

BTW, setting CONF_FILE also worked, but the setting never got saved when I closed the build setting window.  So I guess I'll stick with adding it to CACHED_CONF_FILE.

[Amanda Hsieh]

mkjones said:

My <board>.cong file was in the boards directory, and had the same name as the board.  It does not get loaded automatically.

It has to add <board>.cong manually in the VS Code. West build would load it automatically. 

mkjones said:

setting CONF_FILE also worked, but the setting never got saved when I closed the build setting window. 

VS Code would not save it. You have to check the build configuration of VS Code every time.