nRF21540EK integration with nRF5340dk

[matt_m]

Hi there,

We are trying to integrate an nRF21540EK shield onto our nRF5340DK. Following the instructions on the following link (https://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/nrf/ug_radio_fem.html#ug-radio-fem-nrf21540-ek-programming) we were able to set up the hardware but we are struggling to find a guide on how to configure the software.

We are seeking to use the nRF21540EK in conjunction with the "Bluetooth: Peripheral UART" sample found in the nRF connect SDK and would like to be able to control the gain and antenna select functions on the nRF21540.

Thanks,

Matt

[matt_m]

Hi Kazi, thanks for the reply. We tried to replicate your setup on the nRF5340 but we seem to be getting some errors. I have a few questions:

• Do we need to use an overlay file to describe how the FEM is connected to the nRF5340 or this handled by adding the shield to the project’s CMakeLists.txt file?
• Are the variables TRANSMIT_POWER_dBm and CONFIG_MPSL_FEM_NRF21540_TX_GAIN_DB referring to the tx power/gain of the nRF5340 and the nRF21540 respectively and do they have to be configured separately?
•  The project builds but we are getting the error "Set Tx power err: -5 reason 0x00". We previously had trouble configuring the tx power of the nRF5340 using the zephyr controller and had to use the soft device controller, is this error related?

Many thanks,

Matt

[Kazi Afroza Sultana]

Hello Matt,

I am adding here the complete project of this application. You can control the external FEM with GPIOs which is supported. I assume LNA is fixed or not supported so, has set this RX gain zero like this CONFIG_MPSL_FEM_NRF21540_RX_GAIN_DB=0. Power amplifier gain is supported which has 20 dbM value (CONFIG_MPSL_FEM_NRF21540_TX_GAIN_DB=20). 

adv_nRF21540_20dBm.zip

You can get the idea of overlay file and CMakeList.tst file from here. 

Best Regards,

Kazi Afroza Sultana