nRF52840 with SDK 15.2 running with BLE and Data Length Extension

RE: nRF52840 with SDK 15.2 running with BLE and Data Length Extension

SebastianGutzwiller — Wed, 20 May 2020 06:52:41 GMT

Hi,

Thanks, now I see what you meant.

Our actual workaround which works with that smartphone is that the slave don't send any GAP connection parameter update requests and accepts all from the master. With the drawback that the slave could run out of its current budget.

Cheers
Sebastian

RE: nRF52840 with SDK 15.2 running with BLE and Data Length Extension

Amanda Hsieh — Fri, 15 May 2020 13:51:13 GMT

Hi,

If it doesn't disconnect, then you will have event71. Did you do a similar thing in the first part connection at frame #941? If so, you can take a look at its next event 72 what the master sent.

--Amanda H.

RE: nRF52840 with SDK 15.2 running with BLE and Data Length Extension

SebastianGutzwiller — Thu, 14 May 2020 09:03:50 GMT

Hi Amanda,

Thanks for the detailed explanation.

The actual project status is that this phone (it's actually my own and it is updated) is one of the first which shows that behaviour.

It is planned that we conduct broader DLE tests with the most used smartphones. Therefore it is important for us to understand exactly what is happening here.

You are talking about a connection event 71. I don't see it in the wireshark trace. Do you mean LE LL Instant 70? What packet should the master send at that event?

Cheers
Sebastian

RE: nRF52840 with SDK 15.2 running with BLE and Data Length Extension

Amanda Hsieh — Fri, 08 May 2020 11:03:18 GMT

Hi,

It seems to be related to the LL_CONNECTION_UPDATE_REQ. After the new connection interval should have taken effect, the nrf does not respond anymore.
It is maybe the master/phone packet is sent outside the the allowed window,i.e. not between instant+transmitWindowOffset and instant+transmitWindowOffset + transmitWindowSize. Those will stop transmission of the Handle Value Notification. Then, we go back to check log "ndk_s7_disc_dur_login2_filt" again, and find:

At event 71, the new connection parameters should have taken effect... but the master is not sending any packets at connection event 71.

Maybe the user could try to update the software on the phone. Maybe there is a software update pending for the phone.

This log "ndk_s7_disc_dur_login2_filt" points to a problem with the phone. And if you only see the problem with certain phones, then that also supports that.

-Amanda H.

RE: nRF52840 with SDK 15.2 running with BLE and Data Length Extension

SebastianGutzwiller — Tue, 05 May 2020 12:58:16 GMT

As you can see in the trace file it was about 13 times a successful sd_ble_gatts_hvx().

The hvn_tx_queue_size is 6.

The procedure for handling the transmit queue is implemented exactly as you described it.

RE: nRF52840 with SDK 15.2 running with BLE and Data Length Extension

SebastianGutzwiller — Tue, 05 May 2020 12:50:26 GMT

/cfs-file/__key/communityserver-discussions-components-files/4/nordicapp_5F00_sdk16_5F00_dle_5F00_s7_5F00_connect_5F00_wal_5F00_4.log

That's the trace file logged with one good connection & one failed at the end.

RE: nRF52840 with SDK 15.2 running with BLE and Data Length Extension

Amanda Hsieh — Tue, 05 May 2020 10:52:41 GMT

Hi,

[quote user="SebastianGutzwiller"]SoftDevice stops sending BLE_GATTS_EVT_HVN_TX_COMPLETE filling up the transmit queue on the application side[/quote]

How many NRF_SUCCESS is returned by the sd_ble_gatts_hvx before the softdevice stops sending BLE_GATTS_EVT_HVN_TX_COMPLETE?

How do you know the softdevice stops sending BLE_GATTS_EVT_HVN_TX_COMPLETE? Could you provide the debug log?

How big is your hvn_tx_queue_size ?

[quote user="SebastianGutzwiller"]variant #2 of https://infocenter.nordicsemi.com/index.jsp?topic=%2Fcom.nordic.infocenter.s140.api.v7.0.1%2Findex.html[/quote]

I think you mean this GATTS Handle Value Notification.

[quote user="SebastianGutzwiller"]Can one monitor that HVN transmission in more details?[/quote]

The sd_ble_gatts_hvx can keep track of the available queue element count for notifications by following the procedure below:

Store initial queue element count in a variable.
Decrement the variable, which stores the currently available queue element count, by one when a call to this function returns NRF_SUCCESS.
Increment the variable, which stores the current available queue element count, by the count variable in BLE_GATTS_EVT_HVN_TX_COMPLETE event.

-Amanda H.

RE: nRF52840 with SDK 15.2 running with BLE and Data Length Extension

SebastianGutzwiller — Mon, 04 May 2020 12:19:38 GMT

I updated the SoftDevice to version 7.0.1 and still have the connection supervision timeouts in about 1 of 7 connections with some smartphones.

In those cases I can confirm that the SoftDevice called with sd_ble_gatts_hvx() is always returning NRF_SUCCESS and the SoftDevice stops sending BLE_GATTS_EVT_HVN_TX_COMPLETE filling up the transmit queue on the application side (variant #2 of https://infocenter.nordicsemi.com/index.jsp?topic=%2Fcom.nordic.infocenter.s140.api.v7.0.1%2Findex.html).

Can the transmission of the Handle Value Notification be prevented by events outside of the SoftDevice? Can one monitor that HVN transmission in more details?

RE: nRF52840 with SDK 15.2 running with BLE and Data Length Extension

Amanda Hsieh — Thu, 12 Mar 2020 09:33:24 GMT

Hi,

In the ndk_s7_disc_dur_login2_filt.pcap, I see one of the disconnection is terminated by the phone. Another one, I don't have enough information to know which side caused the disconnection.

You can compile with the debug mode to print out full the info to debug.

-Amanda H.

RE: nRF52840 with SDK 15.2 running with BLE and Data Length Extension

SebastianGutzwiller — Thu, 12 Mar 2020 07:05:57 GMT

I can guarantee that the nRF52840 does not get a reset nor call sd_ble_gap_disconnect() nor that the smartphone goes out of range.

If you look at 'ndk_s7_disc_dur_login2_filt.pcap' how big are the chances that the error is happening on the Nordic board?

RE: nRF52840 with SDK 15.2 running with BLE and Data Length Extension

Amanda Hsieh — Tue, 03 Mar 2020 14:38:14 GMT

Hi,

[quote user="SebastianGutzwiller"]The reason for disconnect on nRF side has been integrated long time ago, see initial description.[/quote]

From your nrf-Connect-Log-1.txt, we saw the disconnection reason is Connection terminated by peer (status 19). If you send disconnect request from your peripheral, you get onConnectionStateChanged with status = 19 (0x13 = GATT CONN TERMINATE PEER USER). That is why we want you to print the disconnect reason in the code. However, you indicated the disconnect reason is HMI error code 0x08 and you also said:

[quote user="SebastianGutzwiller"]After several tries with 'nRF Connect' no supervision timeout happened, see one example with BLE_HCI_LOCAL_HOST_TERMINATED_CONNECTION in ndk_s7_nrf_connect.pcapng[/quote]

You have to identify what is the disconnection reason.

For BLE_HCI_LOCAL_HOST_TERMINATED_CONNECTION, you have to check if you are calling sd_ble_gap_disconnect(). For BLE_HCI_CONNECTION_TIMEOUT, you will get status = 8 (0x08 = GATT CONN TIMEOUT) on RF connect side if you just restart your device, or you go out of range, or other reason of loss of comms.

What is the Android OS on your phone? Not sure this post can help or not.

If you are debugging this with SES, you might find this video useful.

-Amanda H.

RE: nRF52840 with SDK 15.2 running with BLE and Data Length Extension

SebastianGutzwiller — Tue, 03 Mar 2020 07:57:48 GMT

As my employer is getting impatient I wanted to ask how big are the chances that the error is happening on the Nordic board?

RE: nRF52840 with SDK 15.2 running with BLE and Data Length Extension

Amanda Hsieh — Fri, 28 Feb 2020 08:17:55 GMT

Hi,

Sorry for the mistake. I forgot you want to test with the mobile phone.

You could try the Heart Rate Application example.

-Amanda H.

RE: nRF52840 with SDK 15.2 running with BLE and Data Length Extension

SebastianGutzwiller — Thu, 27 Feb 2020 12:28:37 GMT

Obviously no.

RE: nRF52840 with SDK 15.2 running with BLE and Data Length Extension

SebastianGutzwiller — Thu, 27 Feb 2020 10:15:27 GMT

Can I connect to it with a Smartphone app to see if that connection supervision timeout is happening?

RE: nRF52840 with SDK 15.2 running with BLE and Data Length Extension

Amanda Hsieh — Thu, 27 Feb 2020 10:03:38 GMT

Hi,

[quote user="SebastianGutzwiller"]Is there a BLE with DLE project from Nordic which I can use for further tests?[/quote]

Yes, please see ATT_MTU Throughput Example.

-Amanda H.

RE: nRF52840 with SDK 15.2 running with BLE and Data Length Extension

SebastianGutzwiller — Thu, 27 Feb 2020 09:49:26 GMT

We are logging calls of sd_ble_gap_disconnect(). In our traces I don't see any calls to it.

We don't have any code containing on_conn_params_evt().

The reason for disconnect on nRF side has been integrated long time ago, see initial description.

Is there a BLE with DLE project from Nordic which I can use for further tests?

RE: nRF52840 with SDK 15.2 running with BLE and Data Length Extension

Amanda Hsieh — Thu, 27 Feb 2020 08:17:06 GMT

Hi,

It seems like the nRF terminated the connection. Maybe you can check if you are calling sd_ble_gap_disconnect() in the function on_conn_params_evt().

If you are calling sd_ble_gap_disconnect(), you will see 0x16 (BLE_HCI_LOCAL_HOST_TERMINATED_CONNECTION) as disconnect reason on nRF side. Disconnect reason can be printed on the nRF side in ble_evt_handler() like this, snippet:

case BLE_GAP_EVT_DISCONNECTED:
NRF_LOG_INFO("Disconnected reason: 0x%x",p_ble_evt->evt.gap_evt.params.disconnected.reason)

-Amanda H.

RE: nRF52840 with SDK 15.2 running with BLE and Data Length Extension

SebastianGutzwiller — Wed, 26 Feb 2020 11:35:51 GMT

/cfs-file/__key/communityserver-discussions-components-files/4/nrf-Connect-Log-1.txt

RE: nRF52840 with SDK 15.2 running with BLE and Data Length Extension

SebastianGutzwiller — Wed, 26 Feb 2020 10:19:14 GMT

/cfs-file/__key/communityserver-discussions-components-files/4/ndk_5F00_s7_5F00_nrf_5F00_connect.pcapng

RE: nRF52840 with SDK 15.2 running with BLE and Data Length Extension

Amanda Hsieh — Wed, 26 Feb 2020 08:26:37 GMT

Could you kindly provide the completed nRF Connect log while it behaves as the first example in ndk_s7_nrf_connect.pcapng? We need the detail in the nRF Connect log. Thanks.

-Amanda H.

RE: nRF52840 with SDK 15.2 running with BLE and Data Length Extension

SebastianGutzwiller — Tue, 25 Feb 2020 16:49:57 GMT

After several tries with 'nRF Connect' no supervision timeout happened, see one example with BLE_HCI_LOCAL_HOST_TERMINATED_CONNECTION in ndk_s7_nrf_connect.pcapng

RE: nRF52840 with SDK 15.2 running with BLE and Data Length Extension

Amanda Hsieh — Tue, 25 Feb 2020 10:06:32 GMT

Hi,

[quote user="SebastianGutzwiller"]1) Open point: We need to check what Bluetooth event can be traced on those Android smartphones.[/quote]

You could use nRF Connect for Mobile and provide the log.

-Amanda H.

RE: nRF52840 with SDK 15.2 running with BLE and Data Length Extension

SebastianGutzwiller — Tue, 25 Feb 2020 07:21:11 GMT

1) Open point: We need to check what Bluetooth event can be traced on those Android smartphones.

2) The trace was recorded with a firmware containing S140 v.6.1.1.

RE: nRF52840 with SDK 15.2 running with BLE and Data Length Extension

Amanda Hsieh — Tue, 25 Feb 2020 06:43:10 GMT

Hi,

The master(phone) sent the last packet, and it looks like nRF52840 stopped responding

1) Did you get BLE_HCI_CONNECTION_TIMEOUT on both nRF and phone side?

2) Looks like you are using S140 v.6.1.0, you should test with S140 v.6.1.1, and see if the same behavior can be reproduced with S140 v.6.1.1
Edited

-Amanda H.