[bluetooth]# connect F8:C3:D1:B0:5A:3A
Attempting to connect to F8:C3:D1:B0:5A:3A
[CHG] Device F8:C3:D1:B0:5A:3A Connected: yes
Connection successful
[Amazfit GTR 2]# menu gatt
Menu gatt:
Available commands:
-------------------
list-attributes [dev/local]                       List attributes
select-attribute <attribute/UUID>                 Select attribute
attribute-info [attribute/UUID]                   Select attribute
read [offset]                                     Read attribute value
write <data=xx xx ...> [offset] [type]            Write attribute value
acquire-write                                     Acquire Write file descriptor
release-write                                     Release Write file descriptor
acquire-notify                                    Acquire Notify file descriptor
release-notify                                    Release Notify file descriptor
notify <on/off>                                   Notify attribute value
clone [dev/attribute/UUID]                        Clone a device or attribute
register-application [UUID ...]                   Register profile to connect
unregister-application                            Unregister profile
register-service <UUID> [handle]                  Register application service.
unregister-service <UUID/object>                  Unregister application service
register-includes <UUID> [handle]                 Register as Included service in.
unregister-includes <Service-UUID><Inc-UUID>      Unregister Included service.
register-characteristic <UUID> <Flags=read,write,notify...> [handle] Register application characteristic
unregister-characteristic <UUID/object>           Unregister application characteristic
register-descriptor <UUID> <Flags=read,write...> [handle] Register application descriptor
unregister-descriptor <UUID/object>               Unregister application descriptor
back                                              Return to main menu
version                                           Display version
quit                                              Quit program
exit                                              Quit program
help                                              Display help about this program
export                                            Print environment variables
[Amazfit GTR 2]# select-attribute 00000009-0000-3512-2118-0009af100700
[Amazfit GTR 2]# notify on
No attribute selected
[CHG] Device F8:C3:D1:B0:5A:3A ServicesResolved: yes
[CHG] Device F8:C3:D1:B0:5A:3A Paired: yes
[CHG] Device F8:C3:D1:B0:5A:3A ServicesResolved: no
[CHG] Device F8:C3:D1:B0:5A:3A Connected: no



----------


btmon:

piggz@adam-laptop ~ $ sudo btmon
Bluetooth monitor ver 5.63
= Note: Linux version 5.16.14-1-default (x86_64)                                                                                                                                     0.537725
= Note: Bluetooth subsystem version 2.22                                                                                                                                             0.537729
= New Index: DC:53:60:51:00:C6 (Primary,USB,hci0)                                                                                                                             [hci0] 0.537730
= Open Index: DC:53:60:51:00:C6                                                                                                                                               [hci0] 0.537730
= Index Info: DC:53:60:51:00:C6 (Intel Corp.)                                                                                                                                 [hci0] 0.537731
@ MGMT Open: bluetoothd (privileged) version 1.21                                                                                                                           {0x0001} 0.537732
< HCI Command: LE Set Scan Parameters (0x08|0x000b) plen 7                                                                                                                 #1 [hci0] 9.719672
        Type: Passive (0x00)
        Interval: 60.000 msec (0x0060)
        Window: 60.000 msec (0x0060)
        Own address type: Public (0x00)
        Filter policy: Accept all advertisement (0x00)
> HCI Event: Command Complete (0x0e) plen 4                                                                                                                                #2 [hci0] 9.833744
      LE Set Scan Parameters (0x08|0x000b) ncmd 1
        Status: Success (0x00)
< HCI Command: LE Set Scan Enable (0x08|0x000c) plen 2                                                                                                                     #3 [hci0] 9.833768
        Scanning: Enabled (0x01)
        Filter duplicates: Enabled (0x01)
> HCI Event: Command Complete (0x0e) plen 4                                                                                                                                #4 [hci0] 9.834745
      LE Set Scan Enable (0x08|0x000c) ncmd 2
        Status: Success (0x00)
> HCI Event: LE Meta Event (0x3e) plen 29                                                                                                                                  #5 [hci0] 9.893808
      LE Advertising Report (0x02)
        Num reports: 1
        Event type: Connectable undirected - ADV_IND (0x00)
        Address type: Random (0x01)
        Address: 4E:4A:CC:0C:78:46 (Resolvable)
        Data length: 17
        Flags: 0x1a
          LE General Discoverable Mode
          Simultaneous LE and BR/EDR (Controller)
          Simultaneous LE and BR/EDR (Host)
        TX power: 12 dBm
        Company: Apple, Inc. (76)
          Type: Unknown (16)
          Data: 501cf52e89
        RSSI: -79 dBm (0xb1)
> HCI Event: LE Meta Event (0x3e) plen 28                                                                                                                                 #6 [hci0] 10.019799
      LE Advertising Report (0x02)
        Num reports: 1
        Event type: Connectable undirected - ADV_IND (0x00)
        Address type: Random (0x01)
        Address: 58:66:E9:A5:2D:DB (Resolvable)
        Data length: 16
        Flags: 0x06
          LE General Discoverable Mode
          BR/EDR Not Supported
        Service Data (UUID 0xfe2c): 0000
        TX power: -10 dBm
        Service Data (UUID 0xfe03):
        RSSI: -82 dBm (0xae)
> HCI Event: LE Meta Event (0x3e) plen 43                                                                                                                                 #7 [hci0] 10.058806
      LE Advertising Report (0x02)
        Num reports: 1
        Event type: Connectable undirected - ADV_IND (0x00)
        Address type: Random (0x01)
        Address: EF:51:CD:3C:7E:8F (Static)
        Data length: 31
        Flags: 0x06
          LE General Discoverable Mode
          BR/EDR Not Supported
        Company: Anhui Huami Information Technology Co., Ltd. (343)
          Data: 02ffffffffffffffffffffffffffffffff03ef51cd3c7e8f
        RSSI: -72 dBm (0xb8)
> HCI Event: LE Meta Event (0x3e) plen 40                                                                                                                                 #8 [hci0] 10.079812
      LE Advertising Report (0x02)
        Num reports: 1
        Event type: Scannable undirected - ADV_SCAN_IND (0x02)
        Address type: Random (0x01)
        Address: 79:F9:F9:87:54:DA (Resolvable)
        Data length: 28
        16-bit Service UUIDs (complete): 1 entry
          Google (0xfe9f)
        Service Data (UUID 0xfe9f): 0000000000000000000000000000000000000000
        RSSI: -79 dBm (0xb1)
> HCI Event: LE Meta Event (0x3e) plen 20                                                                                                                                 #9 [hci0] 10.480812
      LE Advertising Report (0x02)
        Num reports: 1
        Event type: Non connectable undirected - ADV_NONCONN_IND (0x03)
        Address type: Random (0x01)
        Address: C8:38:3A:F0:5A:7F (Static)
        Data length: 8
        Company: Apple, Inc. (76)
          Type: Unknown (18)
          Data: 0001
        RSSI: -87 dBm (0xa9)
> HCI Event: LE Meta Event (0x3e) plen 43                                                                                                                                #10 [hci0] 11.205858
      LE Advertising Report (0x02)
        Num reports: 1
        Event type: Connectable undirected - ADV_IND (0x00)
        Address type: Random (0x01)
        Address: F8:C3:D1:B0:5A:3A (Static)
        Data length: 31
        Flags: 0x02
          LE General Discoverable Mode
        Company: Anhui Huami Information Technology Co., Ltd. (343)
          Data: 02ffffffffffffffffffffffffffffffff03f8c3d1b05a3a
        RSSI: -57 dBm (0xc7)
< HCI Command: LE Set Scan Enable (0x08|0x000c) plen 2                                                                                                                   #11 [hci0] 11.205957
        Scanning: Disabled (0x00)
        Filter duplicates: Disabled (0x00)
> HCI Event: Command Complete (0x0e) plen 4                                                                                                                              #12 [hci0] 11.258813
      LE Set Scan Enable (0x08|0x000c) ncmd 2
        Status: Success (0x00)
< HCI Command: LE Create Connection (0x08|0x000d) plen 25                                                                                                                #13 [hci0] 11.258884
        Scan interval: 60.000 msec (0x0060)
        Scan window: 60.000 msec (0x0060)
        Filter policy: Accept list is not used (0x00)
        Peer address type: Random (0x01)
        Peer address: F8:C3:D1:B0:5A:3A (Static)
        Own address type: Public (0x00)
        Min connection interval: 30.00 msec (0x0018)
        Max connection interval: 50.00 msec (0x0028)
        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                                                                                                                                #14 [hci0] 11.259812
      LE Create Connection (0x08|0x000d) ncmd 2
        Status: Success (0x00)
> HCI Event: LE Meta Event (0x3e) plen 19                                                                                                                                #15 [hci0] 12.060874
      LE Connection Complete (0x01)
        Status: Success (0x00)
        Handle: 3585
        Role: Central (0x00)
        Peer address type: Random (0x01)
        Peer address: F8:C3:D1:B0:5A:3A (Static)
        Connection interval: 50.00 msec (0x0028)
        Connection latency: 0 (0x0000)
        Supervision timeout: 420 msec (0x002a)
        Central clock accuracy: 0x00
@ MGMT Event: Device Connected (0x000b) plen 44                                                                                                                     {0x0001} [hci0] 12.060941
        LE Address: F8:C3:D1:B0:5A:3A (Static)
        Flags: 0x00000008
          Connection Locally Initiated
        Data length: 31
        Flags: 0x02
          LE General Discoverable Mode
        Company: Anhui Huami Information Technology Co., Ltd. (343)
          Data: 02ffffffffffffffffffffffffffffffff03f8c3d1b05a3a
< HCI Command: LE Read Remote Used Features (0x08|0x0016) plen 2                                                                                                         #16 [hci0] 12.061170
        Handle: 3585
> HCI Event: Command Status (0x0f) plen 4                                                                                                                                #17 [hci0] 12.061869
      LE Read Remote Used Features (0x08|0x0016) ncmd 1
        Status: Success (0x00)
> HCI Event: LE Meta Event (0x3e) plen 12                                                                                                                                #18 [hci0] 12.107883
      LE Read Remote Used Features (0x04)
        Status: Success (0x00)
        Handle: 3585
        Features: 0x01 0x00 0x00 0x00 0x00 0x00 0x00 0x00
          LE Encryption
< HCI Command: LE Start Encryption (0x08|0x0019) plen 28                                                                                                                 #19 [hci0] 12.107977
        Handle: 3585
        Random number: 0x200e8e7861b656fa
        Encrypted diversifier: 0xa313
        Long term key: 70ff87784e4a4394af70214bedf33a1d
> HCI Event: Command Status (0x0f) plen 4                                                                                                                                #20 [hci0] 12.108868
      LE Start Encryption (0x08|0x0019) ncmd 1
        Status: Success (0x00)
> HCI Event: Encryption Change (0x08) plen 4                                                                                                                             #21 [hci0] 12.506947
        Status: Success (0x00)
        Handle: 3585
        Encryption: Enabled with AES-CCM (0x01)
< ACL Data TX: Handle 3585 flags 0x00 dlen 7                                                                                                                             #22 [hci0] 12.507730
      ATT: Exchange MTU Request (0x02) len 2
        Client RX MTU: 517
> ACL Data RX: Handle 3585 flags 0x02 dlen 7                                                                                                                             #23 [hci0] 12.556081
      ATT: Exchange MTU Request (0x02) len 2
        Client RX MTU: 247
< ACL Data TX: Handle 3585 flags 0x00 dlen 7                                                                                                                             #24 [hci0] 12.556256
      ATT: Exchange MTU Response (0x03) len 2
        Server RX MTU: 247
> HCI Event: Number of Completed Packets (0x13) plen 5                                                                                                                   #25 [hci0] 12.557869
        Num handles: 1
        Handle: 3585
        Count: 1
> HCI Event: Number of Completed Packets (0x13) plen 5                                                                                                                   #26 [hci0] 12.606870
        Num handles: 1
        Handle: 3585
        Count: 1
> ACL Data RX: Handle 3585 flags 0x02 dlen 7                                                                                                                             #27 [hci0] 12.655972
      ATT: Exchange MTU Response (0x03) len 2
        Server RX MTU: 252
< ACL Data TX: Handle 3585 flags 0x00 dlen 7                                                                                                                             #28 [hci0] 12.656235
      ATT: Read Request (0x0a) len 2
        Handle: 0x0032
> HCI Event: Number of Completed Packets (0x13) plen 5                                                                                                                   #29 [hci0] 12.705870
        Num handles: 1
        Handle: 3585
        Count: 1
> ACL Data RX: Handle 3585 flags 0x02 dlen 12                                                                                                                            #30 [hci0] 12.755936
      ATT: Read Response (0x0b) len 7
        Value: 01570140000101
< ACL Data TX: Handle 3585 flags 0x00 dlen 7                                                                                                                             #31 [hci0] 12.756045
      ATT: Read Request (0x0a) len 2
        Handle: 0x0016
> HCI Event: Number of Completed Packets (0x13) plen 5                                                                                                                   #32 [hci0] 12.805900
        Num handles: 1
        Handle: 3585
        Count: 1
> ACL Data RX: Handle 3585 flags 0x02 dlen 19                                                                                                                            #33 [hci0] 12.856058
      ATT: Read Response (0x0b) len 14
        Value: 416d617a66697420475452203200
< ACL Data TX: Handle 3585 flags 0x00 dlen 7                                                                                                                             #34 [hci0] 12.856400
      ATT: Read Request (0x0a) len 2
        Handle: 0x0018
> HCI Event: Number of Completed Packets (0x13) plen 5                                                                                                                   #35 [hci0] 12.905890
        Num handles: 1
        Handle: 3585
        Count: 1
> ACL Data RX: Handle 3585 flags 0x02 dlen 7                                                                                                                             #36 [hci0] 15.256110
      ATT: Exchange MTU Request (0x02) len 2
        Client RX MTU: 247
< ACL Data TX: Handle 3585 flags 0x00 dlen 7                                                                                                                             #37 [hci0] 15.256346
      ATT: Exchange MTU Response (0x03) len 2
        Server RX MTU: 247
> HCI Event: Number of Completed Packets (0x13) plen 5                                                                                                                   #38 [hci0] 15.306998
        Num handles: 1
        Handle: 3585
        Count: 1
> ACL Data RX: Handle 3585 flags 0x02 dlen 11                                                                                                                            #39 [hci0] 16.006117
      ATT: Read By Type Request (0x08) len 6
        Handle range: 0x0001-0xffff
        Attribute type: Characteristic (0x2803)
< ACL Data TX: Handle 3585 flags 0x00 dlen 27                                                                                                                            #40 [hci0] 16.006335
< ACL Data TX: Handle 3585 flags 0x01 dlen 27                                                                                                                            #41 [hci0] 16.006347
< ACL Data TX: Handle 3585 flags 0x01 dlen 8                                                                                                                             #42 [hci0] 16.006351
      ATT: Read By Type Response (0x09) len 57
        Attribute data length: 7
        Attribute data list: 8 entries
        Handle: 0x0002
        Value: 020300002a
        Handle: 0x0004
        Value: 020500012a
        Handle: 0x0006
        Value: 020700a62a
        Handle: 0x0009
        Value: 200a00052a
        Handle: 0x000c
        Value: 0a0d00292b
        Handle: 0x000e
        Value: 020f002a2b
        Handle: 0x0010
        Value: 0211003a2b
        Handle: 0x0013
        Value: 021400502a
> HCI Event: Number of Completed Packets (0x13) plen 5                                                                                                                   #43 [hci0] 16.057055
        Num handles: 1
        Handle: 3585
        Count: 1
> HCI Event: Number of Completed Packets (0x13) plen 5                                                                                                                   #44 [hci0] 16.058037
        Num handles: 1
        Handle: 3585
        Count: 1
> HCI Event: Number of Completed Packets (0x13) plen 5                                                                                                                   #45 [hci0] 16.059032
        Num handles: 1
        Handle: 3585
        Count: 1
> ACL Data RX: Handle 3585 flags 0x02 dlen 11                                                                                                                            #46 [hci0] 16.106108
      ATT: Read By Type Request (0x08) len 6
        Handle range: 0x0014-0xffff
        Attribute type: Characteristic (0x2803)
< ACL Data TX: Handle 3585 flags 0x00 dlen 9                                                                                                                             #47 [hci0] 16.106365
      ATT: Error Response (0x01) len 4
        Read By Type Request (0x08)
        Handle: 0x0014
        Error: Attribute Not Found (0x0a)
> HCI Event: Number of Completed Packets (0x13) plen 5                                                                                                                   #48 [hci0] 16.157103
        Num handles: 1
        Handle: 3585
        Count: 1
> ACL Data RX: Handle 3585 flags 0x02 dlen 11                                                                                                                            #49 [hci0] 16.206140
      ATT: Read By Type Request (0x08) len 6
        Handle range: 0x0001-0xffff
        Attribute type: Device Name (0x2a00)
< ACL Data TX: Handle 3585 flags 0x00 dlen 18                                                                                                                            #50 [hci0] 16.206737
      ATT: Read By Type Response (0x09) len 13
        Attribute data length: 12
        Attribute data list: 1 entry
        Handle: 0x0003
        Value: 426c75655a20352e3633
> HCI Event: Number of Completed Packets (0x13) plen 5                                                                                                                   #51 [hci0] 16.257082
        Num handles: 1
        Handle: 3585
        Count: 1
> ACL Data RX: Handle 3585 flags 0x02 dlen 11                                                                                                                            #52 [hci0] 19.438030
      ATT: Read By Type Request (0x08) len 6
        Handle range: 0x0001-0xffff
        Attribute type: Characteristic (0x2803)
< ACL Data TX: Handle 3585 flags 0x00 dlen 27                                                                                                                            #53 [hci0] 19.438239
< ACL Data TX: Handle 3585 flags 0x01 dlen 27                                                                                                                            #54 [hci0] 19.438255
< ACL Data TX: Handle 3585 flags 0x01 dlen 8                                                                                                                             #55 [hci0] 19.438260
      ATT: Read By Type Response (0x09) len 57
        Attribute data length: 7
        Attribute data list: 8 entries
        Handle: 0x0002
        Value: 020300002a
        Handle: 0x0004
        Value: 020500012a
        Handle: 0x0006
        Value: 020700a62a
        Handle: 0x0009
        Value: 200a00052a
        Handle: 0x000c
        Value: 0a0d00292b
        Handle: 0x000e
        Value: 020f002a2b
        Handle: 0x0010
        Value: 0211003a2b
        Handle: 0x0013
        Value: 021400502a
> HCI Event: Number of Completed Packets (0x13) plen 5                                                                                                                   #56 [hci0] 19.457169
        Num handles: 1
        Handle: 3585
        Count: 1
> HCI Event: Number of Completed Packets (0x13) plen 5                                                                                                                   #57 [hci0] 19.458229
        Num handles: 1
        Handle: 3585
        Count: 1
> HCI Event: Number of Completed Packets (0x13) plen 5                                                                                                                   #58 [hci0] 19.459252
        Num handles: 1
        Handle: 3585
        Count: 1
> ACL Data RX: Handle 3585 flags 0x02 dlen 11                                                                                                                            #59 [hci0] 19.506287
      ATT: Read By Type Request (0x08) len 6
        Handle range: 0x0014-0xffff
        Attribute type: Characteristic (0x2803)
< ACL Data TX: Handle 3585 flags 0x00 dlen 9                                                                                                                             #60 [hci0] 19.506388
      ATT: Error Response (0x01) len 4
        Read By Type Request (0x08)
        Handle: 0x0014
        Error: Attribute Not Found (0x0a)
> HCI Event: Number of Completed Packets (0x13) plen 5                                                                                                                   #61 [hci0] 19.557245
        Num handles: 1
        Handle: 3585
        Count: 1
> ACL Data RX: Handle 3585 flags 0x02 dlen 11                                                                                                                            #62 [hci0] 19.606321
      ATT: Read By Type Request (0x08) len 6
        Handle range: 0x0001-0xffff
        Attribute type: Device Name (0x2a00)
< ACL Data TX: Handle 3585 flags 0x00 dlen 18                                                                                                                            #63 [hci0] 19.606726
      ATT: Read By Type Response (0x09) len 13
        Attribute data length: 12
        Attribute data list: 1 entry
        Handle: 0x0003
        Value: 426c75655a20352e3633
> HCI Event: Number of Completed Packets (0x13) plen 5                                                                                                                   #64 [hci0] 19.657210
        Num handles: 1
        Handle: 3585
        Count: 1







< HCI Command: Disconnect (0x01|0x0006) plen 3                                                                                                                           #65 [hci0] 44.885194
        Handle: 3585
        Reason: Remote User Terminated Connection (0x13)
> HCI Event: Command Status (0x0f) plen 4                                                                                                                                #66 [hci0] 45.006315
      Disconnect (0x01|0x0006) ncmd 1
        Status: Success (0x00)
> HCI Event: Disconnect Complete (0x05) plen 4                                                                                                                           #67 [hci0] 45.008258
        Status: Success (0x00)
        Handle: 3585
        Reason: Connection Terminated By Local Host (0x16)
@ MGMT Event: Device Disconnected (0x000c) plen 8                                                                                                                   {0x0001} [hci0] 45.008311
        LE Address: F8:C3:D1:B0:5A:3A (Static)
        Reason: Connection terminated by local host (0x02)