Thingy 53 and nRF21540 Frontend (Bluetooth Mesh) - How to set TX power via SPI

[cb235]

Hi there,

I am currently facing the following problem. I have a thingy53 running as sensor server application (bluetooth mesh). To extend the range I want to increase the tx power using the built-in nRF21540 module. Because I need to try different TX levels I need to interface the nRF21540 via SPI.

Since I am new to Zephyr I wasn't able to get it running. I am facing several issues during initializing the SPI. I know that the node has the label "nrf_radio_fem_spi" in the devicetree, but creating the pointer to the device object already fails.

So right now I am asking if there is any example code which shows how to set the TX power level of nRF21540 via SPI using thingy 53? Unfortunately I couldn't find any.

Thanks in advance!

[Bendik Heiskel]

Hi,

The control of the nRF21540 is handled by the MPSL FEM driver. This means you won't need to implement the SPI communication yourself.

The easiest way to configure the TX output power is to just use CONFIG_BT_CTLR_TX_PWR_ANTENNA to set the final output power at compile time.

 

Best regards,

Bendik

[cb235]

Hi Bendik,

thanks for your reply. Using the "CONFIG_BT_CTLR_TX_PWR_ANTENNA" works well.

In further use cases I need to adjust the tx power during runtime, so I will need to implement the spi communication.

Best Regards