How to determine Tx Power Level Value?

[Yalcin Akdogan]

Hi,

It is not transparent to me, how can I determine this value? Is it a best practices value? I want to implement Tx Power profile but I don't know where to get this value.

Another question is, how RSSI value goes in advertising packet. Is it responsibility of HW+SoftDevice or Implementer of a service?

Thanks in advance, Yalcin

[Ole Morten]

There isn't any way to get the current TX power level from the stack, so if you need it you have to keep track of it in your application, based on your calls to sd_ble_gap_tx_power_set(). The default TX power level of S110 is 0 dBm.

For an implementation example of the TX Power Service, you can refer to the ble_app_proximity example in the SDK.

[Yalcin Akdogan]

Hi Ole, thanks for your answer.

In the proximity example ble_app_proximity, the TX_POWER service makes the characteristic tx_power_level available to client (readable). It is set to an initial value and is not changed over the time. Is that the whole intention?

[Ole Morten]

Yes, that's the way the TX Power Service is defined by the Bluetooth SIG. The document describing it is available here: https://www.bluetooth.org/docman/handlers/downloaddoc.ashx?doc_id=239393