Bluetooth: Scanner consumption while scanning

[Tobi15]

Hi,

I open this issue because i think i'm missing something to completely understand my power consumption measure on a Zephyr I opened this question because I think I am missing something to fully understand my power consumption measurement on a Zephyr scanner.

I am using a nrf52840dk with a power profiler kit 2 to measure the power consumption of my board.

Zephyr version: 3.2.99

Based on the examples provided in Zephyr for bluetooth, I created a basic application that scans continuously. I used the following scan parameters:

struct bt_le_scan_param scan_param = {
  .type       = BT_HCI_LE_SCAN_PASSIVE,
  .options    = BT_LE_SCAN_OPT_NONE,
  .interval   = 48,     // 48 * 0.625 = 90 ms
  .window     = 48,  //  48 * 0.625 = 30 ms
};

with the following configurations :

CONFIG_BT=y
CONFIG_BT_BROADCASTER=n
CONFIG_BT_OBSERVER=y
CONFIG_BT_DEBUG_LOG=n

#deep sleep
CONFIG_PM=y
CONFIG_CONSOLE=n
CONFIG_SERIAL=n

I got the following measurement:

What is missing for me to understand: What are the peaks that appear every millisecond? They only appear when CONFIG_OBSERVER is on.

Can someone help me to understand this?

Thank you very much in advance!

[kruithofa]

@cvinayak can you have a look?
@Tobi15 alternatively you can ask the question at the discord channel: https://discord.com/channels/720317445772017664/733036837576376341