Bluetooth Mesh TX power on nRF52

RE: Bluetooth Mesh TX power on nRF52

Andrea Pieretti — Fri, 22 Feb 2019 11:44:25 GMT

I'd like to not modify SDK source files.

I've try to use the network_opt_set after mesh_stack_init, but this lead to a mesh assert.

RE: Bluetooth Mesh TX power on nRF52

bjorn-spockeli — Mon, 23 Jul 2018 13:26:55 GMT

Please do. I could not find any API that allows you to modify the default TX power at run-time in the Mesh SDK API reference.

RE: Bluetooth Mesh TX power on nRF52

luciom — Mon, 23 Jul 2018 11:04:35 GMT

Hi Bjiorn,

I'm developing a BLE Mesh application and I'm working with Mesh SDK 2.1.1.

I also need to high the Mesh TX power and I will try the way you suggested (set_default_broadcast_configuration).

I wonder if there was a way to do the same from the user code without modifying the SDK sources.

Thank you

Lucio

RE: Bluetooth Mesh TX power on nRF52

bjorn-spockeli — Wed, 28 Mar 2018 11:48:03 GMT

Arij: No, this question only covers how to set the default TX output power of the mesh devices, see Thomas Stenersen's answer.

RE: Bluetooth Mesh TX power on nRF52

Arij — Wed, 28 Mar 2018 10:57:35 GMT

bjorn-spockeli: Does this help me to enable relaying in light switch example ?

RE: Bluetooth Mesh TX power on nRF52

bjorn-spockeli — Tue, 13 Mar 2018 07:11:42 GMT

Piotr B: You should be able to set the default TX output power with the set_default_broadcast_configuration()function in advertiser.c.

RE: Bluetooth Mesh TX power on nRF52

PB — Mon, 12 Mar 2018 15:03:43 GMT

I've lloked into `radio_config_config()` but it seems that whatever is set by it is overwritten frequently by radio switching between scanning and advertising in Mesh SDK 1.0.0. How did you approach changing TX power for mesh messages?

RE: Bluetooth Mesh TX power on nRF52

Thomas Stenersen — Tue, 14 Nov 2017 13:02:47 GMT

Updated my answer with information for v0.10.0+ :)

RE: Bluetooth Mesh TX power on nRF52

bjorn-spockeli — Tue, 14 Nov 2017 12:44:57 GMT

overheat (aaronxu): I think that you should be able to use radio_config_config() to set the tx power by passing it a radio_config_t struct

RE: Bluetooth Mesh TX power on nRF52

aaronxu — Fri, 10 Nov 2017 03:32:03 GMT

Hi, looks it's changed in v0.10 version. I cannot find "radio_tx_power_set"

RE: Bluetooth Mesh TX power on nRF52

jpreston — Fri, 22 Sep 2017 15:36:16 GMT

I believe you are correct. I was using 4 as my value. See the answer below for the solution to the problem.

RE: Bluetooth Mesh TX power on nRF52

Matt — Thu, 21 Sep 2017 20:24:32 GMT

I believe the accepted argument values for sd_ble_gap_tx_power_set() are -40, -20, -16, -12, -8, -4, 0, 4 (dbm). Please verify with the softdevice documentation.

RE: Bluetooth Mesh TX power on nRF52

Thomas Stenersen — Thu, 21 Sep 2017 18:18:54 GMT

I'm glad to hear that!

RE: Bluetooth Mesh TX power on nRF52

jpreston — Thu, 21 Sep 2017 18:04:44 GMT

Thanks, Thomas! That helps me a lot after getting a lot of search results for the function I was trying to use instead...

RE: Bluetooth Mesh TX power on nRF52

Thomas Stenersen — Thu, 21 Sep 2017 17:58:41 GMT

Hi jpreston,

The mesh stack operates within a SoftDevice timeslot and implements its own advertiser and scanner. To modify the TX output power of the device, I believe you only have to call the void radio_tx_power_set(radio_tx_power_t tx_power) function in mesh/include/core/radio.h. You could also set the default at compile time in mesh/src/core/radio.c in radio_init().

Edit for v0.10.0+

In the v0.10.0 a new bearer layer appeared and changed this around a bit. There is a concept of an "advertiser instance": advertiser_t in mesh/bearer/include/advertiser.h. This means that the stack can instantiate and use any number of advertisers concurrently. Each advertiser owns a broadcast_t structure, which owns the lower level radio configurations like which access address, what advertising channels and what radio_config_t to use.

To answer your question directly. To change the TX power of the mesh itself, you would really have to change the values used in the individual advertiser_t instances. However, all advertisers used in the mesh are set up with default parameters by the set_default_broadcast_configuration() in advertiser.c:268. In that function you can change the default TX power among other things.

Best,
Thomas