Hello! My name is peter. This is probably a bit off topic but: Since about 2 years I am working ambitiously on connecting a GoPro to an Odroid via HTTP, UDP and BLE in order to get a powerful node-red controlled dashcam/balckbox for my cars (fleet control). (please see: https://github.com/cepoon/GoProRemote, https://github.com/KonradIT/goprowifihack, https://github.com/sepp89117/GoPro-Multiple-Smart-Remote-ESP8266) However I stumbled over a thread: #96, which's owner forwarded me to your mailing list as my last resort: and figured that you are deep into debugging of BLE connections. because of our long developement period we are "stuck" in a somewhat older hardware/kernel config, unfortunately: Odroid C2 with BluetoothModule2 (CSR8510 A10) Ubuntu 18.04 (Kernel 3.16.85+) WifiModule 5A (concurrent mode (STA+Client) on hostapd 2.9) Bluez 5.53 btusb 0.7 (- GoPro Hero5 black) However, we do suffer from an comparable annoying problem since more than a year(!). We do have an unstable BLE Connection between Dongle and Gopro. When just paired, the first connection stays up for about 30mins (abortion the is not btmon-itored yet, but can be done), but the reconnect is a problem: gets connected but after 2 - 15 sec: disconnect. Mainly because of: #Issue 1: (btmon) Why is it disconnecting after MTU request? @ Discovering: 0x00 (6) HCI Event: Command Status (0x0f) plen 4 #111 [hci0] 55.051270 LE Create Connection (0x08|0x000d) ncmd 1 Status: Success (0x00) HCI Event: LE Meta Event (0x3e) plen 19 #112 [hci0] 55.626431 LE Connection Complete (0x01) Status: Success (0x00) Handle: 71 Role: Master (0x00) Peer address type: Random (0x01) Peer address: C9:0F:D9:47:48:B4 (Static) Connection interval: 70.00 msec (0x0038) Connection latency: 0 (0x0000) Supervision timeout: 420 msec (0x002a) Master clock accuracy: 0x00 @ Device Connected: C9:0F:D9:47:48:B4 (2) flags 0x0000 << ACL Data TX: Handle 71 flags 0x00 dlen 7 #113 [hci0] 55.627789 ATT: Exchange MTU Request (0x02) len 2 Client RX MTU: 517 HCI Event: Disconnect Complete (0x05) plen 4 #114 [hci0] 56.035562 Status: Success (0x00) Handle: 71 Reason: Connection Failed to be Established (0x3e) @ Device Disconnected: C9:0F:D9:47:48:B4 (2) reason 0 #issue 2: btmon: Error: Timeout/ Disconnect after attribute not found!? (main issue obviously) @ Discovering: 0x00 (6) << HCI Command: LE Create Connect.. (0x08|0x000d) plen 25 #102 [hci0] 21.277573 Scan interval: 60.000 msec (0x0060) Scan window: 30.000 msec (0x0030) Filter policy: White list is not used (0x00) Peer address type: Random (0x01) Peer address: C9:0F:D9:47:48:B4 (Static) Own address type: Public (0x00) Min connection interval: 50.00 msec (0x0028) Max connection interval: 70.00 msec (0x0038) Connection latency: 0 (0x0000) Supervision timeout: 420 msec (0x002a) Min connection length: 0.000 msec (0x0000) Max connection length: 0.000 msec (0x0000) HCI Event: Command Status (0x0f) plen 4 #103 [hci0] 21.281234 LE Create Connection (0x08|0x000d) ncmd 1 Status: Success (0x00) HCI Event: LE Meta Event (0x3e) plen 19 #104 [hci0] 21.474300 LE Connection Complete (0x01) Status: Success (0x00) Handle: 71 Role: Master (0x00) Peer address type: Random (0x01) Peer address: C9:0F:D9:47:48:B4 (Static) Connection interval: 70.00 msec (0x0038) Connection latency: 0 (0x0000) Supervision timeout: 420 msec (0x002a) Master clock accuracy: 0x00 @ Device Connected: C9:0F:D9:47:48:B4 (2) flags 0x0000 << ACL Data TX: Handle 71 flags 0x00 dlen 7 #105 [hci0] 21.475604 ATT: Exchange MTU Request (0x02) len 2 Client RX MTU: 517 HCI Event: Number of Completed Packets (0x13) plen 5 #106 [hci0] 21.786387 Num handles: 1 Handle: 71 Count: 1 ACL Data RX: Handle 71 flags 0x02 dlen 7 #107 [hci0] 21.849441 ATT: Exchange MTU Response (0x03) len 2 Server RX MTU: 517 << ACL Data TX: Handle 71 flags 0x00 dlen 7 #108 [hci0] 21.849849 ATT: Read Request (0x0a) len 2 Handle: 0x0004 HCI Event: Number of Completed Packets (0x13) plen 5 #109 [hci0] 21.919448 Num handles: 1 Handle: 71 Count: 1 ACL Data RX: Handle 71 flags 0x02 dlen 15 #110 [hci0] 21.989485 ATT: Read Response (0x0b) len 10 Value: 476f50726f2038353339 << ACL Data TX: Handle 71 flags 0x00 dlen 7 #111 [hci0] 21.989865 ATT: Read Request (0x0a) len 2 Handle: 0x0006 HCI Event: Number of Completed Packets (0x13) plen 5 #112 [hci0] 22.059476 Num handles: 1 Handle: 71 Count: 1 ACL Data RX: Handle 71 flags 0x02 dlen 7 #113 [hci0] 22.135894 ATT: Read Response (0x0b) len 2 Value: 8000 << ACL Data TX: Handle 71 flags 0x00 dlen 7 #114 [hci0] 22.136253 ATT: Read Request (0x0a) len 2 Handle: 0x000e HCI Event: Number of Completed Packets (0x13) plen 5 #115 [hci0] 22.199508 Num handles: 1 Handle: 71 Count: 1 ACL Data RX: Handle 71 flags 0x02 dlen 6 #116 [hci0] 22.269695 ATT: Read Response (0x0b) len 1 Value: 05 << ACL Data TX: Handle 71 flags 0x00 dlen 7 #117 [hci0] 22.270106 ATT: Read Request (0x0a) len 2 Handle: 0x0020 HCI Event: Number of Completed Packets (0x13) plen 5 #118 [hci0] 22.339554 Num handles: 1 Handle: 71 Count: 1 ACL Data RX: Handle 71 flags 0x02 dlen 12 #119 [hci0] 22.409721 ATT: Read Response (0x0b) len 7 Value: 00000000000000 << ACL Data TX: Handle 71 flags 0x00 dlen 11 #120 [hci0] 22.410113 ATT: Read By Group Type Request (0x10) len 6 Handle range: 0x0001-0xffff Attribute group type: Primary Service (0x2800) HCI Event: Number of Completed Packets (0x13) plen 5 #121 [hci0] 22.479592 Num handles: 1 Handle: 71 Count: 1 ACL Data RX: Handle 71 flags 0x02 dlen 27 #122 [hci0] 22.549760 ACL Data RX: Handle 71 flags 0x01 dlen 9 #123 [hci0] 22.551041 ATT: Read By Group Type Response (0x11) len 31 Attribute data length: 6 Attribute group list: 5 entries Handle range: 0x0001-0x0001 UUID: Generic Attribute Profile (0x1801) Handle range: 0x0002-0x0008 UUID: Generic Access Profile (0x1800) Handle range: 0x0009-0x000b UUID: Tx Power (0x1804) Handle range: 0x000c-0x000f UUID: Battery Service (0x180f) Handle range: 0x0010-0x0020 UUID: Device Information (0x180a) << ACL Data TX: Handle 71 flags 0x00 dlen 9 #124 [hci0] 22.551281 ATT: Write Request (0x12) len 4 Handle: 0x000f Data: 0100 HCI Event: Number of Completed Packets (0x13) plen 5 #125 [hci0] 22.695655 Num handles: 1 Handle: 71 Count: 1 ACL Data RX: Handle 71 flags 0x02 dlen 5 #126 [hci0] 22.759830 ATT: Write Response (0x13) len 0 << ACL Data TX: Handle 71 flags 0x00 dlen 11 #127 [hci0] 22.760241 ATT: Read By Group Type Request (0x10) len 6 Handle range: 0x0021-0xffff Attribute group type: Primary Service (0x2800) HCI Event: Number of Completed Packets (0x13) plen 5 #128 [hci0] 22.829698 Num handles: 1 Handle: 71 Count: 1 ACL Data RX: Handle 71 flags 0x02 dlen 26 #129 [hci0] 22.899859 ATT: Read By Group Type Response (0x11) len 21 Attribute data length: 20 Attribute group list: 1 entry Handle range: 0x0021-0x002c UUID: Vendor specific (b5f90001-aa8d-11e3-9046-0002a5d5c51b) << ACL Data TX: Handle 71 flags 0x00 dlen 11 #130 [hci0] 22.900311 ATT: Read By Group Type Request (0x10) len 6 Handle range: 0x002d-0xffff Attribute group type: Primary Service (0x2800) HCI Event: Number of Completed Packets (0x13) plen 5 #131 [hci0] 23.039754 Num handles: 1 Handle: 71 Count: 1 ACL Data RX: Handle 71 flags 0x02 dlen 12 #132 [hci0] 23.109915 ATT: Read By Group Type Response (0x11) len 7 Attribute data length: 6 Attribute group list: 1 entry Handle range: 0x002d-0x0041 UUID: GoPro, Inc. (0xfea6) << ACL Data TX: Handle 71 flags 0x00 dlen 11 #133 [hci0] 23.110286 ATT: Read By Group Type Request (0x10) len 6 Handle range: 0x0042-0xffff Attribute group type: Primary Service (0x2800) HCI Event: Number of Completed Packets (0x13) plen 5 #134 [hci0] 23.185785 Num handles: 1 Handle: 71 Count: 1 ACL Data RX: Handle 71 flags 0x02 dlen 26 #135 [hci0] 23.319981 ATT: Read By Group Type Response (0x11) len 21 Attribute data length: 20 Attribute group list: 1 entry Handle range: 0x0042-0x0047 UUID: Vendor specific (b5f90090-aa8d-11e3-9046-0002a5d5c51b) << ACL Data TX: Handle 71 flags 0x00 dlen 11 #136 [hci0] 23.320349 ATT: Read By Group Type Request (0x10) len 6 Handle range: 0x0048-0xffff Attribute group type: Primary Service (0x2800) HCI Event: Number of Completed Packets (0x13) plen 5 #137 [hci0] 23.389838 Num handles: 1 Handle: 71 Count: 1 ACL Data RX: Handle 71 flags 0x02 dlen 9 #138 [hci0] 23.458793 ATT: Error Response (0x01) len 4 Read By Group Type Request (0x10) Handle: 0x0048 Error: Attribute Not Found (0x0a) HCI Event: Disconnect Complete (0x05) plen 4 #139 [hci0] 24.160066 Status: Success (0x00) Handle: 71 Reason: Connection Timeout (0x08) @ Device Disconnected: C9:0F:D9:47:48:B4 (2) reason 1 for sure there are Authentification failures too, but I cannot btmon-capture 'em right now. However, it is really hard to find somebody who has a glue what is going on here, and where the best, we should start to debug. So please can you help us any further. We are struggeling for a solution on this for years. greets peter
