Setting Connection TX Power

[Paul M.]

Hello everyone,

I am using the nrf5340 for a Bluetooth project with the nrf sdk 2.4.0. Since a stable connection is essential, I want to increase the connection tx power to 3 dbm. When staying at the standard 0 dbm I get connection losses.

I could already set the advertiesemt tx power to 3 dbm bei adding 

CONFIG_BT_CTLR_TX_PWR_PLUS_3=y

to my prj.conf and hci_rpmsg.conf but was not able to change increase the tx power while connected. I would like to either set it permanently using a config like i did for the advertiesement, or dynamically in the code.

How can I do that?

Thank you very much and best regards,

Paul

[Amanda Hsieh]

Hi, 

How to set the output power is described here. The critical aspect when using the nRF5340 is that you also need to set this for the network core, which is done by modifying the hci_rpmsg.conf file in the child_image subfolder of your project. Try to delete the build folder and build again. Check the .config under build/hci_rpmsg/zephyr to see whether the config takes effect. 

You can refer to Bluetooth: HCI Power Control to dynamically control the Tx power of a Bluetooth LE Controller using HCI vendor-specific commands.

Regards,
Amanda H.