PPK2 and Power Profiler desktop: time scale way off

RE: PPK2 and Power Profiler desktop: time scale way off

RenanSP — Thu, 27 Jul 2023 10:13:55 GMT

But after tweaking many options on BIOS (most of which I don't understand) it improved from 32% to 48% of real time being captured. That also improved a bit the ringing that the PPK2 was displaying on both the current graph and the LA graph (the signal was fine as I probed it with an oscilloscope right at the PPK2 PCB).

But still, the LA was drawing the wrong duty cycle, and the ammeter losing samples and hallucinating about ringing. Finally, I tried a live Linux USB drive ( Pop!_OS 22.04 ) on a borrowed INTEL laptop and connected PPK2 to it without disturbing the test circuit. All the problems disappeared.

As the two pictures show, apparently the only thing PPK2 seems to get right on AMD systems currently is the average current. Everything else is dependent on chipset's luck.

RE: PPK2 and Power Profiler desktop: time scale way off

RenanSP — Wed, 26 Jul 2023 20:51:56 GMT

I have the very same issue: the recorded time is only 32% of real time. I tried multiple USB ports (2.0 / 3.1), cables, OS (Windows 10 and Linux Pop!_OS 22.04) and a USB hub. The best combination still didn't go over 34%.
This is really messing with my calculations.

My motherboard is an "MSI - AMD AM4 mATX B350M gaming pro" (chipset = B350M).
I will see if there are BIOS updates available and report back.

Reporting back: I updated to the latest BIOS (2023-05-23-beta) and the problem persists.

RE: PPK2 and Power Profiler desktop: time scale way off

Joakim Jakobsen — Fri, 14 Apr 2023 12:12:07 GMT

Hi.

We don't know what is causing the issue as of now.

[quote user="TheBronx"]

I connected it to a USB3 hub and it works fine on my AMD machine.

I have been experimenting with the python PPK2 API and discovered that just reading a fixed amount of bytes from the serial port takes longer when connected directly compared to the USB hub.

[/quote]

Like previously commented, a possible workaround could be to connect the PPK through a USB hub.

Br,
Joakim

RE: PPK2 and Power Profiler desktop: time scale way off

Joakim Jakobsen — Thu, 13 Apr 2023 10:56:49 GMT

Thank you for your feedback.

I will continue to investigate the issue. Will confer with our PPK and SW developers.

Br,
Joakim

RE: PPK2 and Power Profiler desktop: time scale way off

iiNSaNe — Thu, 13 Apr 2023 10:55:10 GMT

I am also affected with the new chipset x670e AM5 with ComboAM5PI 1.0.0.6. There are no other problems with any other USB device. What exactly should I tell AMD? That the Nordic PPK2 device don't work, but everything else works smoothly? I already know what the answer will be. If the device only works with Intel chipsets, shouldn't it be mentioned on sale?

RE: PPK2 and Power Profiler desktop: time scale way off

TheBronx — Thu, 13 Apr 2023 10:35:27 GMT

As I reported initially I updated to the latest BIOS available to see if that fixed the issue but it didn't.

The BIOS version for my MSI B450 Tomahawk Max II is 7C02vH9.
According to the changelog for that version: https://www.msi.com/Motherboard/B450-TOMAHAWK-MAX-II/support

Update to AGESA ComboAm4v2PI 1.2.0.7.

So that's a much more recent version than 1.2.0.2 of course, and the problem persists.
Also the issue that AMD resolved with that release, back in 2021, was a series of random USB disconnections. But our problem is not that the device disconnects, it is connected all the time, it just doesn't work well.

I am pretty sure this is a different issue unfortunately.

RE: PPK2 and Power Profiler desktop: time scale way off

Joakim Jakobsen — Thu, 13 Apr 2023 07:25:13 GMT

Hi!

A couple of reports on the same issue here;

This is a previously known issue with AMD chipsets. If you are not using AMD and still experience the same issue, please let me know.

From what I can see, this should have been fixed in a later release of BIOS, so I recommend updating that to try and solve the problem.

A statement from AMD from two years ago:
"AMD has prepared AGESA 1.2.0.2 to deploy this update, and we plan to distribute 1.2.0.2 to our motherboard partners for integration in about a week. Customers can expect downloadable BIOSes containing AGESA 1.2.0.2 to begin with beta updates in early April. If you continue to experience intermittent USB connectivity issues after updating your system to AGESA 1.2.0.2, we encourage you to open a ticket with AMD Customer Support."

Br,
Joakim

RE: PPK2 and Power Profiler desktop: time scale way off

Olfox — Mon, 03 Apr 2023 14:20:16 GMT

Hi , I have also the timing issue. When i click on 10sec for a screen , the capture full windows is like more than two times the selected value. The selection window is also not giving the good duration too:

My advertising period is 10sec, i can also count it. But selected time said 3.566sec , that's not correct.

RE: PPK2 and Power Profiler desktop: time scale way off

sheggy012 — Tue, 21 Mar 2023 21:18:48 GMT

I just bought a new computer and now have exactly the same problems. I hope the problem is solved quickly.

- System: ASUS System Product Name
- BIOS: American Megatrends Inc. ALASKA - 1072009
- CPU: 1 x AMD Ryzen 7 7700X 8-Core Processor 4.5 GHz 16 cores (8 physical)
- Memory: 16.9 GB free of 31.1 GB total
- Filesystem: C: (NTFS) 953.1 GB 62.4% used

- OS: Microsoft Windows 11 Pro (10.0.22621) Windows ia32

Previously with Intel CPU no problems at all. Perhaps there is a correlation.

RE: PPK2 and Power Profiler desktop: time scale way off

Joakim Jakobsen — Mon, 23 Jan 2023 22:10:13 GMT

[quote user="TheBronx"]I keep wondering one thing though: if there is some problem or limitation that makes the communication too slow, so measurements are lost, why does the problem happen at any sample rate? If I set it to 100k and I can only get 32k, well then anything below 32k should work fine right? But no.[/quote]

The sampling rate is actually always 100kHz. When selecting anything below you will still have a sample rate of 100kHz but use an average filter.
That is most likely the reason.

[quote user="TheBronx"]Maybe it is just this particular motherboard? Maybe it is all B450 chipsets? Maybe other AMD chipsets too? Maybe it happens in some Intel boards too who knows.[/quote]

Not really sure how widespread this problem is. I'll do some investigating and get back to you!

Br,
Joakim

RE: PPK2 and Power Profiler desktop: time scale way off

TheBronx — Mon, 23 Jan 2023 21:21:06 GMT

I would be happy to try things and help debug this issue. But I have no experience writing drivers, and BIOS is black magic to me. So I am a bit clueless.

On one hand I feel like it has to be possible to make the device work, on the other I feel like if it fails in windows and linux maybe the problem is deeper than the Power Profiler app (or any other app) can reach.

I keep wondering one thing though: if there is some problem or limitation that makes the communication too slow, so measurements are lost, why does the problem happen at any sample rate? If I set it to 100k and I can only get 32k, well then anything below 32k should work fine right? But no.

Of course I don't know what the protocol looks like, I only took the python API code and played with it a bit. But isn't it weird?

BTW I think the app should show a clear and visible warning when the actual sample rate doesn't match the expected sample rate. And maybe collect statistics about how many times this warning is being triggered to see how widespread (or not) this problem might be. Cause I don't think my system is that uncommon. Maybe it is just this particular motherboard? Maybe it is all B450 chipsets? Maybe other AMD chipsets too? Maybe it happens in some Intel boards too who knows.

And thank you for the answer Joakim. I think the product is pretty cool. I was very disappointed at first but after discovering the workaround I used it for quite some time and I like it, app is simple yet powerful, very nice!

RE: PPK2 and Power Profiler desktop: time scale way off

Joakim Jakobsen — Mon, 23 Jan 2023 20:55:42 GMT

Have you tried on windows? Do you see the same issue there?

Edit: Just saw that you mentioned windows in the original post.

RE: PPK2 and Power Profiler desktop: time scale way off

Joakim Jakobsen — Mon, 23 Jan 2023 20:55:13 GMT

Thank you for the detailed description.

Seems you already found both the cause and workaround for the issuee. I will report this internally to our developers.

[quote user="TheBronx"]But why does reading take so much longer when connected to a USB port directly compared to having a USB hub in between?[/quote]

Not sure. I'll do some research as to why this happens.

Br,
Joakim

RE: PPK2 and Power Profiler desktop: time scale way off

TheBronx — Sat, 21 Jan 2023 11:04:11 GMT

I connected it to a USB3 hub and it works fine on my AMD machine.

I have been experimenting with the python PPK2 API and discovered that just reading a fixed amount of bytes from the serial port takes longer when connected directly compared to the USB hub.

When connected to the hub:

Bus 003 Device 023: ID 1915:c00a Nordic Semiconductor ASA PPK2
reading 8192 bytes took 21.00ms
reading 8192 bytes took 20.00ms
reading 8192 bytes took 21.00ms
reading 8192 bytes took 20.00ms
reading 8192 bytes took 22.00ms

When connected directly to one USB port:

Bus 001 Device 031: ID 1915:c00a Nordic Semiconductor ASA PPK2
reading 8192 bytes took 64.00ms
reading 8192 bytes took 64.00ms
reading 8192 bytes took 64.00ms
reading 8192 bytes took 64.00ms

If a sample is 4 bytes this means that:

the hub is able to read 2048 samples every 20ish milliseconds. That is a rate of ~100k samples per second. As expected.
when directly connected it reads 2048 samples per 64ms. That is a rate of 32k samples per second. That is only 32% of the theoretical sample rate.

And if the timing on the graph relies on the 100k theoretical rate, when that rate is in reality only 32% then yeah, 5 seconds would look like only 32% of it, so 1.6 seconds.

But why does reading take so much longer when connected to a USB port directly compared to having a USB hub in between?