Issue on setting tx power peripheral connection when CONFIG_BT_CENTRAL is enabled

[longo92]

hci_pwr_ctrl_with_config_bt_central.zip

I am using the following example as a reference for setting the TX power in a peripheral Bluetooth connection: https://github.com/nrfconnect/sdk-zephyr/tree/v3.6.99-ncs2/samples/bluetooth/hci_pwr_ctrl.

I am on latest nordic connect sdk: 2.7.0.

I am using the nRF21540-DK.

The example works fine when the device is configured to operate as a peripheral only. However, when I enable the central role by setting CONFIG_BT_CENTRAL=y in prj.conf, the SoftDevice asserts an error when trying to change the TX power during a connection as peripheral.

ASSERTION FAIL [0] @ WEST_TOPDIR/nrf/subsys/bluetooth/controller/hci_driver.c:278
SoftDevice Controller ASSERT: 49, 1332

What does the assert mean? Since the SoftDevice code is closed i cannot look into the file and line number i suppose. 

Thanks a lot,

Alessandro

[longo92]

Exactly i simply add the CONFIG_BT_CENTRAL=y and the issue is on the peripheral connection.

CONFIG_BT=y

CONFIG_LOG=y

CONFIG_BT_PERIPHERAL=y

CONFIG_BT_CENTRAL=y

CONFIG_BT_HRS=y

CONFIG_BT_DEVICE_APPEARANCE=833

CONFIG_BT_DEVICE_NAME="Dynamic test beacon"

CONFIG_BT_CTLR_ADVANCED_FEATURES=y

CONFIG_BT_CTLR_CONN_RSSI=y

CONFIG_BT_CTLR_TX_PWR_DYNAMIC_CONTROL=y

 

[Kazi Afroza Sultana]

Hello,

Can you please share your project file so I can reproduce?

[longo92]

In the attachments section of the ticket i've uploaded a .zip file of the project.

nordic connect sdk: 2.7.0

board used: nRF21540-DK

After flashing the fw, if you connect to the device using your nrf connect smartphone app the problem arises.

[Sigurd]

Hi!

Kazi is out of office, so I'm replying instead.

I tested the sample. I don't get the same assert as you get (I get a MPU fault instead) , but there is indeed a issue with this sample on NCS 2.7.0.

You can solve it by adding this:

CONFIG_BT_CTLR_LE_POWER_CONTROL=y

It will be fixed in the next NCS release.

[longo92]

Hi Sigurd,

using CONFIG_BT_CTLR_LE_POWER_CONTROL=y works.

The MPU error, i suppose, you should fix by using CONFIG_MPU_ALLOW_FLASH_WRITE=y ( or CONFIG_FLASH=y), because for setting dynamic tx power on connection handle, the BT-TX thread needs to write flash (not pretty sure of that).

[Sigurd]

longo92 said:

using CONFIG_BT_CTLR_LE_POWER_CONTROL=y works.

Great to hear that it worked.