AX200/201 BLE data length extension not expected behavior (incorrect time)

KostasS · ‎07-25-2022

Hello,

I am using 2 laptops one with an AX200 and the other with an AX201 adapter. The laptop is used as a master and a custom board (BLE 5.0) as a slave in BLE connection.

I am facing the following problem:

As observed using a BLE sniffer on wireshark, when the board is connected to a laptop using the AX200/201 the custom board initiates a LL_LENGTH_REQ with the following parameters:

Max RX octets: 140

Max RX time: 2000 microseconds

Max TX octets: 140

Max TX time: 2000 microseconds

And gets an LL_LENGTH_RSP from the master with the following

Max RX octets: 251

Max RX time: 328 microseconds

Max TX octets: 251

Max TX time: 9101 microseconds

Even if the request is for 251 octets/2120usec, the response still has the Max RX time fixed to 328 microseconds, which is not adequate for sending 251 bytes. As a result the packets are then split in 27/67 bytes long fragments (for 1mbps/2mbps PHY respectively) which affects both the connection speed and stability.

I have done the same tests using a BLE dongle or my mobile phone as master and the result is the expected

Max RX octets: 251

Max RX time: 2120 microseconds

Max TX octets: 251

Max TX time: 2120 microseconds

This looks a lot like this issue on the AX 9260 adapter

AC 9260 BLE data length extension problem

Having the AX200 perform as expected is very important, since it is the one shipped with the laptops we are using for testing our hardware.

The above results were the same when tested with the latest 22.150.0 driver.

On AX200 I randomly get the correct connection parameters but this happens every 1 in 10 or more attempts. On the AX201 I never get the correct RX time.

Could you please let me know why this is happening?

Thanks!

PS: Some additional info,

- Results were the same on Windows 10 and Windows 11

- The above measurements are done using wireshark on an NRF Dongle

- The custom board is based on nrf52840, running the s140 softdevice stack

- The laptops used for testing were Microsoft Surface Go 2/3 (AX200) and HP Probooks 450 G8 on i5 and i7 CPUs (AX201) with same result.

DeividA_Intel · ‎07-26-2022

Hello KostasS,

Thank you for posting on the Intel® communities. I am sorry to know that you are having issues with your Intel® Wi-Fi 6 AX200 (Gig+) and Intel® Wi-Fi 6 AX201.

In order to better assist you, please try the following:

1. Are these custom devices built by you?

2. Have you experienced the same issues with older drivers from Intel and/or laptop manufacturers?

3. How many units were affected?

4. Can you provide more details about the goal of this project?

Regards,

Deivid A.

Intel Customer Support Technician

KostasS · ‎07-27-2022

Hello Deivid,

1. The custom devices are built by us. They have been tested with other laptops and mobile phones as master without any issues. This issue is happening only on the laptops using these 2 Intel adapters

2. The same issue existed with older driver versions as well. The drivers we have tested when we realized it was probably adapter specific were 22.150.0.6 and 21.110.0.3. When testing on laptops using adapters from other manufacturers, we don't have any issues. Also, everything works perfect when we are using USB BLE dongles on the laptops affected by this issue. As a result, we have narrowed it down to the Intel adapters.

3. Every unit we own that's using an intel adapter is affected (they are either AX200 or AX201, so can not test on other Intel adapters)

4. The goal is to have 2 BLE devices and 1 Bluetooth device streaming data to a master device. The BLE devices are using notifications with a connection interval of 10ms, while the Bluetooth device is using a virtual COM port. For the BLE devices we have also tested different connection parameters without any effect on the issue. Also, using only 1 BLE device instead of the full 3 device system does not affect performance; the RX time is still fixed at 328 usec (which does not comply with the 251 bytes length extension)

Please let me know if you need any further information to better pinpoint the root cause of the issue.

Regards,

Kostas

DeividA_Intel · ‎07-27-2022

Hello KostasS,

Based on your issue and the information provided, I recommend you open a post in the Intel Developer Zone. There you will receive the appropriate support on this and other concerns you may have related to this product.

Here you will find the links to access the website and the community forums:

Please keep in mind that this thread will no longer be monitored by Intel.

Regards,

Deivid A.

Intel Customer Support Technician

KostasS · ‎07-29-2022

Hello @DeividA_Intel ,

Thank you for the information provided. Our problem looks very similar to the one described here: AC 9260 BLE data length extension problem which was solved with a new driver version.

Unfortunately, our windows application does not have access to these low level parameters as the data length extension bytes or time, so we can not address this issue on our side.

I would appreciate it if you could point us to the correct way for filing a bug report with Intel's driver development team so that they can fix this issue on the next driver version.

Thank you.

Regards,

Kostas

DeividA_Intel · ‎08-03-2022

Hello KostasS,

I am sorry for the inconvenience. In order to investigate this issue, I will need a report from the Intel® System Support Utility:

Download the Intel® SSU and save the application on your computer: https://www.intel.com/content/www/us/en/download/18377/intel-system-support-utility-for-windows.html
Open the application, check the "Everything" checkbox, and click "Scan" to see the system and device information. The Intel® SSU defaults to the "Summary View" on the output screen following the scan. Click the menu where it says "Summary" to change it to "Detailed View".
To save your scan, click Next and click Save.

Regards,

Deivid A.

Intel Customer Support Technician

KostasS · ‎08-04-2022

Hello Deivid,

Please find attached the report from one of the PCs we use and exhibit this issue.

Regards,

Kostas

DeividA_Intel · ‎08-04-2022

Hello KostasS,

Thank you for the information provided

I will proceed to check the issue internally and post back soon with more details.

Best regards,

Deivid A.

Intel Customer Support Technician

DeividA_Intel · ‎08-09-2022

Hello KostasS,

After checking your thread, I would like to know if you need further assistance.

If so, please provide me with the information requested that I sent to the email address associated with your community profile.

Regards,

Deivid A.

Intel Customer Support Technician

DeividA_Intel · ‎08-11-2022

Hello KostasS,

I was checking your thread and see that we have not heard back from you.

I’m going to close your post, but if you need further assistance, please do not hesitate to create a new post.

Regards,

Deivid A.

Intel Customer Support Technician

DeividA_Intel · ‎08-12-2022

Hello KostasS,

Thanks for replying to my email. I will proceed to check this issue internally, as soon as I have any information or if I need further details I will let you know.

Thanks for your comprehension

Regards,

Deivid A.

Intel Customer Support Technician

DeividA_Intel · ‎08-12-2022

Hello Kostas,

I am still investigating this issue, however, in order to continue I would like to confirm the following with you:

1. Are there any integrations in the affected clients?

2. Are the systems brand new?

3. Are these systems with the latest Windows and BIOS/chipset versions installed?

Regards,

Deivid A.

Intel Customer Support Technician

KostasS · ‎08-16-2022

Hello Deivid,

Thanks for investigating our issue. Regarding your questions,

1. Can you please elaborate further what you mean by "integrations"?

2. We have tested both on brand new systems and systems that have been used previously. We did not observe any different behavior

3. Yes. In some systems we had also tested with earlier driver versions but the issue was still there.

Regards,

Kostas

DeividA_Intel · ‎08-16-2022

Hello Kostas,

Thanks for the information provided. In this case, by integrations I mean if all your systems are using the original wireless card or if they were replaced with a different wireless card.

Please confirm if there are any integrations in the affected clients.

Regards,

Deivid A.

Intel Customer Support Technician

KostasS · ‎08-17-2022

Hello Deivid,

The systems we use are using their original wireless card and no hardware changes have been applied to them. We observe the problem in

- Original Microsoft Surface Go 2 (AX200)

- Original Microsoft Surface Go 3 (AX200)

- HP Probook 450 G8 (AX201)

What the above systems have in common are the wireless cards that are AX200 / AX201. When we used a bluetooth usb dongle from another vendor, instead of the internal Intel one, everything works as expected. Apart from that all the systems have been tested in their original configuration - even removing any wireless mice attached just to make sure we are not in any way affecting their performance.

Regards,

Kostas

DeividA_Intel · ‎08-17-2022

Hello Kostas,

Thanks for the confirmation. I will continue with the investigation and I will inform you about any updates or details as soon as possible.

Regards,

Deivid A.

Intel Customer Support Technician

DeividA_Intel · ‎08-25-2022

Hello Kostas,

I will send you an e-mail to the e-mail address associated with your community profile to gather further information to continue with the investigation.

Best regards,

Deivid A.

Intel Customer Support Technician

KostasS · ‎08-26-2022

Hello Deivid,

I have replied to your e-mail with the information requested. Please feel free to request any further information needed to resolve this issue.

Best regards,

Kostas

DeividA_Intel · ‎08-26-2022

Hello KostasS,

Thanks for the information provided. I will continue with the investigation and I will let you know about any updates as soon as possible.

Regards,

Deivid A.

Intel Customer Support Technician

DeividA_Intel · ‎08-30-2022

Hello KostasS,

I will send you an e-mail to the e-mail address associated with your community profile to gather some information in order to continue with the investigation.

Regards,

Deivid A.

Intel Customer Support Technician

DeividA_Intel · ‎09-01-2022

Hello KostasS,

After checking your thread, I would like to know if you need further assistance.

If so, please reply to the email sent.

Regards,

Deivid A.

Intel Customer Support Technician