S120 Multilink Central app connects, then very quickly disconnects (Reason: BLE_HCI_CONN_FAILED_TO_BE_ESTABLISHED)

RE: S120 Multilink Central app connects, then very quickly disconnects (Reason: BLE_HCI_CONN_FAILED_TO_BE_ESTABLISHED)

mtsunstrum — Tue, 15 Apr 2014 19:19:46 GMT

Thanks Carles,

That worked find, and now my TX address is public, and the Central/Peripheral connect reliably now.

Thx

RE: S120 Multilink Central app connects, then very quickly disconnects (Reason: BLE_HCI_CONN_FAILED_TO_BE_ESTABLISHED)

Carles — Tue, 15 Apr 2014 18:08:19 GMT

Hi there,

Thanks for posting on your progress.

After some searching thru the source code, I don't appear to see a way for the S120 CONNECT_REQ to use a "public" TX address. Is there a way to do that ?

Yes, simply use sd_ble_gap_address_set() with a public address before you call sd_ble_gap_connect().

The last address set will be the one used for future operations.

Carles

RE: S120 Multilink Central app connects, then very quickly disconnects (Reason: BLE_HCI_CONN_FAILED_TO_BE_ESTABLISHED)

mtsunstrum — Tue, 15 Apr 2014 16:22:26 GMT

After some searching thru the source code, I don't appear to see a way for the S120 CONNECT_REQ to use a "public" TX address. Is there a way to do that ?

Thx

RE: S120 Multilink Central app connects, then very quickly disconnects (Reason: BLE_HCI_CONN_FAILED_TO_BE_ESTABLISHED)

mtsunstrum — Tue, 15 Apr 2014 16:01:32 GMT

OK, I see what is happening.

My Peripheral device is "bonding" with only one device. I have to go thru a reset sequence on it to allow it to bond to a different Central.

So I have done that, and now I can CONNECT to my S120 Central.

Only remaining issue appears to be the S120 random TX address. Since the Peripheral I am using appears to store the Central's TX address, I can only connect to it once, because the S120 Central keeps changing its TX address.

I presume there is something in the API that allows me to have the S120 use non-random TX addresses ?

Thx

RE: S120 Multilink Central app connects, then very quickly disconnects (Reason: BLE_HCI_CONN_FAILED_TO_BE_ESTABLISHED)

vich — Tue, 15 Apr 2014 06:49:33 GMT

This is not a problem, S120 Central uses a random static address whereas the peripheral is using public address. Hence, the connect_req contains the tx address type as random for the Init Address.

RE: S120 Multilink Central app connects, then very quickly disconnects (Reason: BLE_HCI_CONN_FAILED_TO_BE_ESTABLISHED)

mtsunstrum — Mon, 14 Apr 2014 22:01:13 GMT

One think I noticed different in the CONNECT_REQ packets ... See packet header field in Wireshark trace

S120 Central:     
    TX address flag = random, RX address flag = public
BLEGUI Central: 
    TX address flag = public, RX address flag = public

I am not immediately familiar with what difference this may cause. Any thoughts on this being a reason for the Peripheral to not respond ?

Thx

RE: S120 Multilink Central app connects, then very quickly disconnects (Reason: BLE_HCI_CONN_FAILED_TO_BE_ESTABLISHED)

mtsunstrum — Mon, 14 Apr 2014 16:17:01 GMT

Commenting on

I have taken a look at your trace. On first glance, it appears that the peer did not receive/listen to the CONNECT_REQ (evident from your application log, as the application found the peer second time before disconnection from the first attempt).

On the second time, it found the peer (peripheral) advertising packet, but also, this second attempt failed to establish a connection with same reason code BLE_HCI_CONN_FAILED_TO_BE_ESTABLISHED.

Thanks

RE: S120 Multilink Central app connects, then very quickly disconnects (Reason: BLE_HCI_CONN_FAILED_TO_BE_ESTABLISHED)

mtsunstrum — Mon, 14 Apr 2014 16:15:22 GMT

Answer to a couple of questions:

Can you reproduce the issue consistently ? Yes, I can. In 95% of the times, I will receive the BLE_HCI_CONN_FAILED_TO_BE_ESTABLISHED termination. There have been two times I have seen in the logs where the connection actually did get established.

S120 Softdevice Version: 1.0.0-1.alpha

I am using BLE Sniffer 0.9.6_BETA_812. I ran with -s option, but I do not see any "logs" folder in my Sniffer directory. But the Wireshark capture is the same as the previous capture.

RE: S120 Multilink Central app connects, then very quickly disconnects (Reason: BLE_HCI_CONN_FAILED_TO_BE_ESTABLISHED)

vich — Mon, 14 Apr 2014 12:20:24 GMT

Hi mtsunstrum,

I have taken a look at your trace. On first glance, it appears that the peer did not receive/listen to the CONNECT_REQ (evident from your application log, as the application found the peer second time before disconnection from the first attempt).

In addition to version information of SD, could you please reproduce the issue while capturing a trace with BLE Sniffer release 0.9.6. Use the 's' option and upload all files from the sniffer's logs folder(capture.pcap, log.txt etc..)

Thanks.

RE: S120 Multilink Central app connects, then very quickly disconnects (Reason: BLE_HCI_CONN_FAILED_TO_BE_ESTABLISHED)

Carles — Mon, 14 Apr 2014 10:53:09 GMT

Hi there,

Unfortunately you cannot control the window size or offset at this time. Regarding the 0x3E failure to connect, I will escalate this internally and see where the issue lies. Thanks for the Wireshark captures, those should be helpful.

EDIT: A couple of questions:

What version of the 1.0.0 SD are you using? 1.0.0-1.alpha or 1.0.0-2.alpha? Can you reproduce the issue consistently, or does it happen randomly?

Thanks,

Carles

RE: S120 Multilink Central app connects, then very quickly disconnects (Reason: BLE_HCI_CONN_FAILED_TO_BE_ESTABLISHED)

mtsunstrum — Mon, 14 Apr 2014 02:53:22 GMT

Clarification. My original Application Log was when the Interval had been set to 60ms (S120 demo app default). I had changed it to 75ms to match what the BLEGUI Central was using.

But notice that the Application Log now shows the following:

[APPL]:[0x00] >> DM_EVT_CONNECTION
[APPL]:[BA 49 B1 EB D7 90]: Connection Established
[APPL]:[0x00] << DM_EVT_CONNECTION

[APPL]:[0x01] >> DM_EVT_CONNECTION
[APPL]:[BA 49 B1 EB D7 90]: Connection Established
[APPL]:[0x01] << DM_EVT_CONNECTION

[APPL]:[0x00] >> DM_EVT_DISCONNECTION Reason:[0x3E]
[APPL]:[0x00] << DM_EVT_DISCONNECTION (Peers connected: 1)

[APPL]:[0x01] >> DM_EVT_DISCONNECTION Reason:[0x3E]
[APPL]:[0x01] << DM_EVT_DISCONNECTION (Peers connected: 0)

This points to some sort of timing issue between Central Peripheral.

The S120 Central picks up on another Peripheral advertisement, and tries to negotiate a 2nd connection.

RE: S120 Multilink Central app connects, then very quickly disconnects (Reason: BLE_HCI_CONN_FAILED_TO_BE_ESTABLISHED)

mtsunstrum — Mon, 14 Apr 2014 02:38:43 GMT

I am using the S120 Softdevice 1.0 and SDK 5.2 on PCA10001 hardware.

My observations on the attached Wireshark files:

See CONNECT_REQ message from Central device S120 Central ( Interval = 75ms Window Size = 6.25 ms, Window Offset = 0 ms ) BLEGUI Central ( Interval = 75ms Window Size = 2.5 ms, Window Offset = 2.5 ms )

Where the connection fails follows the CONNECT_REQ message from Central device. The "master" (Central device) sends an "Empty Data PDU" link establishment packet to the peripheral.

With the BLEGUI Central, the "slave" (Peripheral device) proceeds to successfully establish a connection.

But with the S120 Central, the "slave" (Peripheral device) decides to not respond at all. That is the core reason for the BLE_HCI_CONN_FAILED_TO_BE_ESTABLISHED reason code.

But I don't understand what the peripheral doesn't like in the S120's Central CONNECT_REQ message ... such that the peripheral does not respond.

I don't see anywhere in the S120 code where we can control the value of Window Size/Offset ... to see if that may be a reason for the unsuccessful connect negotiation.

But from what I understand, and in looking at the Wireshark traces, I don't believe Window Size/Offset is the cause of the issue. Likely under control of the SoftDevice. I noticed on packet 13 that the S120 changed the Window Offset to 17.5ms.

Any experts on low level BLE CONNECT_REQ and link level negotiations ? :)

Thx

RE: S120 Multilink Central app connects, then very quickly disconnects (Reason: BLE_HCI_CONN_FAILED_TO_BE_ESTABLISHED)

mtsunstrum — Sun, 13 Apr 2014 06:10:45 GMT

Trying to add attachments again ... looks like files have to be either .txt files or .zip files.

RE: S120 Multilink Central app connects, then very quickly disconnects (Reason: BLE_HCI_CONN_FAILED_TO_BE_ESTABLISHED)

mtsunstrum — Sun, 13 Apr 2014 06:06:41 GMT

I used the nRF51 packet sniffer to capture the CONNECT_REQ differences between using the MultiLink Central, and the BlueGiga Central.

Please see attached Wireshark files.

Any thoughts would be appreciated.

Thx

Wireshark captures.zip