How to change the advertisement transmit power

[chelalv]

I am currently using the nrf52840 dongle as a controller, using the example from https://github.com/pstrueb,
Now we want to change the transmission power of the advertisement.
I modified examples\run_advertiser.py according to bumble\docs\mkdocs\src\platforms\zephyr.md
changetxpower.py
An error will occur: AttributeError: 'HCI_Command_Status_Event' object has no attribute 'return_parameters'
HCI_Write_Tx_Power_Level_Command-error-1.txt
then I comment out the line:
if response.return_parameters.status == hci.HCI_SUCCESS: print(f"TX power set to {response.return_parameters.selected_tx_power_level}")
An error occurs:
DEBUG:bumble.host:### CONTROLLER -> HOST: HCI_COMMAND_STATUS_EVENT:
status: HCI_UNKNOWN_HCI_COMMAND_ERROR
num_hci_command_packets: 1
command_opcode: HCI_WRITE_TX_POWER_LEVEL_COMMAND
HCI_Write_Tx_Power_Level_Command-error-2.txt

[barbibulle]

To check if the command succeeded or not, you should pass check_result=True when calling send_command.
In your case, the command failed because the controller doesn't support this vendor command. You need to ensure that your target configuration enables this optional feature. See https://google.github.io/bumble/platforms/zephyr.html for more details (noted: we should fix that page, because it is misleading in how it checks for errors: it will only work if the command is supported)

[chelalv]

I added check_result=True
response = await device.host.send_command( HCI_Write_Tx_Power_Level_Command( handle_type=HCI_Write_Tx_Power_Level_Command.TX_POWER_HANDLE_TYPE_ADV, connection_handle=0, tx_power_level=10, check_result=True ) )

HCI_LE_SET_EXTENDED_ADVERTISING_PARAMETERS_COMMAND sets advertising_tx_power.
DEBUG:bumble.host:### HOST -> CONTROLLER: HCI_LE_SET_EXTENDED_ADVERTISING_PARAMETERS_COMMAND:
advertising_handle: 0
advertising_event_properties: CONNECTABLE_ADVERTISING|SCANNABLE_ADVERTISING|USE_LEGACY_ADVERTISING_PDUS
primary_advertising_interval_min: 320
primary_advertising_interval_max: 320
primary_advertising_channel_map: CHANNEL_37|CHANNEL_38|CHANNEL_39
own_address_type: RANDOM
peer_address_type: PUBLIC_DEVICE
peer_address: 00:00:00:00:00:00/P
advertising_filter_policy: 0
advertising_tx_power: 127
primary_advertising_phy: LE 1M
secondary_advertising_max_skip: 0
secondary_advertising_phy: LE 1M
advertising_sid: 0
scan_request_notification_enable: 0
Is there a problem with this 127? HCI specifies the Range: -127 to +20

DEBUG:bumble.host:### CONTROLLER -> HOST: HCI_COMMAND_COMPLETE_EVENT:
num_hci_command_packets: 1
command_opcode: HCI_LE_SET_EXTENDED_ADVERTISING_PARAMETERS_COMMAND
return_parameters:
status: HCI_SUCCESS
selected_tx_power: 0
The controller selects 0dbm,

Then use HCI_Write_Tx_Power_Level_Command to set tx_power_level to 10.
The TX power is set to 8dbm.

From the nRF Connect app, the broadcast RSSI has increased.