Zephyr BLE radio RX power consumption

RE: Zephyr BLE radio RX power consumption

jocke — Fri, 05 Jun 2020 13:26:02 GMT

It was a typo in a I2C command to a magnetometer. It didn't go into shutdown mode correctly.

RE: Zephyr BLE radio RX power consumption

Susheel Nuguru — Fri, 05 Jun 2020 13:23:38 GMT

Joachim, can you mention what the root cause was? so that this thread looks complete.

RE: Zephyr BLE radio RX power consumption

jocke — Thu, 04 Jun 2020 15:28:14 GMT

Problem located and fixed. Not related to Zephyr.
Please close this issue.

RE: Zephyr BLE radio RX power consumption

Susheel Nuguru — Tue, 26 May 2020 11:46:33 GMT

Joachim,

The Zephyr Kernel in itself is not adding any timers with that frequency. So it is a bit weird that you see some spikes with that frequency. I have not seen this on my end, so hard to say for me what is causing this spike.

Have you searched through the code to see if there are any k_sleep(100) calls or any k_delayed_work_submit_to_queue with 100ms delay?

If not, we should try to investigate in both the application and also the Zephyr BLE stack.

RE: Zephyr BLE radio RX power consumption

jocke — Mon, 25 May 2020 13:03:16 GMT

Hi Susheel,
Since we have now upgraded to Zephyr 2.0.99, I'm revisiting this problem.
We still see power spikes about every 100ms. We have no timers that tick at this frequency and the power consumption seems consistent with what the specs say that the radio should consume in RX mode.
Have attached two CSV files containing our measurements. One without advertising enabled and one with (advertising every 300ms). In the latter file, you will see higher spikes about every 300ms which is consistent with our advertising rate.

We would appreciate your input on this.

devzone.nordicsemi.com/.../power_5F00_measurements.tar.gz

RE: Zephyr BLE radio RX power consumption

Susheel Nuguru — Wed, 29 Jan 2020 13:22:08 GMT

The Zephyr version you are using is more than a year old. The BLE controller at time was very experimental at that time. I thought you are already made efforts to upgrade to Zephyr version 2.x.x. Do you see the same behavior in that version? I have not used version 1.x.x but in 2.x.x I have not noticed any unusual RX spikes.

If you still want to use the older version, you need to help me out to reproduce this, so that we can attempt to reproduce it and come with a clean workaround.

RE: Zephyr BLE radio RX power consumption

jocke — Wed, 29 Jan 2020 09:43:15 GMT

The measured current consumption is quite consistent with what the radio is supposed to consume in RX mode. Don't remember the exact values right now.
The only external peripherals that we have is a free-running RTC, a magnetometer and an SPI flash. None of these consume the same amount of current or are polled from our application. It's all interrupt based.

RE: Zephyr BLE radio RX power consumption

Susheel Nuguru — Wed, 29 Jan 2020 06:56:29 GMT

Are you sure that it is the RX that is causing the spike every 100ms, it could be a CPU wakeup from a timer and enabling some peripheral that could also cause the spike. If the application is not doing anything to control the RADIO directly, it seems very likely that this 100ms power spike is NOT from the radio.

RE: Zephyr BLE radio RX power consumption

jocke — Mon, 27 Jan 2020 11:32:13 GMT

Hi Susheel,
Sorry for not responding earlier.
Basically, I wish the radio to keep quiet for about 300ms. Both RX and TX.
Currently TX is quiet for 300ms, but the RX seems to trigger every 100ms. That has a very negative impact on our power consumption.

RE: Zephyr BLE radio RX power consumption

Susheel Nuguru — Thu, 05 Dec 2019 12:08:45 GMT

Hi Joachim,

I re assigned this case to myself.
Thomas replied to you in the email regarding this.

But I would like to understand more on what you are trying to achieve so that I can try to assist you.

RE: Zephyr BLE radio RX power consumption

Kenneth — Tue, 03 Dec 2019 15:38:24 GMT

This question is better directed to: https://github.com/zephyrproject-rtos/zephyr#resources

Though you may want to try the latest branch of zephyr just in case first.