Thingy:53 FEM TX Gain adjustment

[GatCode]

Hello,

Is it possible to use the CONFIG_MPSL_FEM_NRF21540_TX_GAIN_DB config option on the app core only? Meaning if I have a proprietary controller, is there a way to adjust the TX gain of the Thingy:53 FEM (nRF21540) without altering the netcore image? Can this be done in hardware? What exactly does the NCS set as the default UICR values (nRF21540 registers)?

Thank you!

[Øyvind]

Hello, 
the DevZone team and Nordic Semiconductor are currently in a summer vacation period, some delays in answers must be expected due to lower staffing during this period. We apologize for the inconvenience. 

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I will need some more time to provide an answer to your question.

Have you looked into our MPSL documentation on nRF21540 usage, or the Working with RF Front-End Modules? The Antenna Selection chapter in Developing with Thingy:53.

Kind regards,
Øyvind

[GatCode]

Hi Øyvind,

thank you very much for your reply!

Yes, I've looked into those chapters but these always refer to the netcore. Given the proprietary controller on the netcore I mentioned before, theses are unfortunately not applicable.

Thanks!

[Øyvind]

Hello again, 

What netcore image are you running on the device? The Thingy:53 Matter Weather Station application configures the CONFIG_MPSL_FEM_NRF21540_TX_GAIN_DB in a child_image fragment multiprotocol_rpmsg.conf. When building the Matter application, the multiprotocol_rpmsg image is built as well. Flashing the matter application will flash both cores with correct image.

Kind regards,
Øyvind

[GatCode]

Hi Øyvind,

for example I tried the Nordic Audio Controller (https://github.com/nrfconnect/sdk-nrf/blob/main/applications/nrf5340_audio/bin/ble5-ctr-rpmsg_3269.hex). Yes but in this case there is no access to the child image given that the before mentioned hex file is the child image.

Thanks!