How do you set Tx power for all power roles

Question

I would like to set the tx power for all roles such that the nRF52840 (s140) never transmits anything above my specified level. This includes advertisements, past connections, future connections, etc. 
 I have the following code to accomplish this: 
 sd_ble_gap_tx_power_set(BLE_GAP_TX_POWER_ROLE_ADV, BLE_CONN_HANDLE_INVALID, transmitPower); sd_ble_gap_tx_power_set(BLE_GAP_TX_POWER_ROLE_SCAN_INIT, BLE_CONN_HANDLE_INVALID, transmitPower); sd_ble_gap_tx_power_set(BLE_GAP_TX_POWER_ROLE_CONN, BLE_CONN_HANDLE_INVALID, transmitPower); 
 Does this cover everything? I don't want to have to set this for each connection/advertisement handle.

Bjørn Kvaale · Accepted Answer

Edit: Very sorry for the wrong answer. I was reminded of this by an application engineer & this answer relates to the mesh sdk. My bad for misreading your question. You are correct that the tx power should be set via the softdevice & not directly via the radio register. 
 The proper answer: This is unfortunately not such a good idea. For the BLE_GAP_TX_POWER_ROLE_ADV, you should set the advertising handle after the advertising_init() function ( see link for more info). For the BLE_GAP_TX_POWER_ROLE_SCAN_INIT, it seems the connection handle is ignored, so that should be fine. For the BLE_GAP_TX_POWER_ROLE_CONN role, you should set the connection handle after you get the CONNECTED event. See the s oftdevice documentation for more info. 
 The old answer is left below (relevant to the Mesh SDK, not nRF 5 SDK): There have been quite a few questions & answers regarding this on the devzone, but unfortunately it is not possible to use sd_ble_gap_tx_power_set() to change the TX transmit power of the radio (for the Mesh SDK!) . 
 The radio_config_config() function in radio_config.c sets the transmit power of the radio. If you take a look at mesh sdk v2.1.1 with the light switch example (take provisioner for example), you can see that the advertiser_instance_init() function in advertiser.c calls set_default_broadcast_configuration(). This function sets the TX radio output power. Then, back in advertiser_instance_init(), the timeout_event callback is called. This function calls schedule_broadcast() if the broadcast context is inactive. Inside schedule_broadcast(), the broadcast_send() function is called, which starts the broadcast_start() callback function. It is broadcast_start() which then finally calls radio_config_config(), which sets the tx power: 
 NRF_RADIO->TXPOWER = p_config->tx_power; 
 To summarize: I believe you will only need to change the radio tx power in set_default_broadcast_configuration().

How do you set Tx power for all power roles

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