安装:
我在一个嵌入式Linux平台上运行BlueZ 5.48,使用Python的example-gatt-server
作为外围设备。 我使用hciconfig hci0 leadv 0
启用广告。
我正在尝试使用iPhone(iOS v12.1.4)上的nRF Connect
连接设备。
这些设备都在我的桌子上,RSSI约为-40dBm,信号水平应该很好。
问题:
我意识到有几个问题,并按优先级顺序列出它们(最重要的在前)。
a) 在iPhone上的nRF Connect
中,我可以看到设备并进行连接,但在30-60秒后,某些原因导致断开连接。 它从未要求我授权配对或输入PIN码。
b) 在Linux中,只要iPhone连接,我就会看到Bluetooth: SMP security requested but not available
不断打印。
c) 在iPhone上,我永远无法在普通蓝牙设备
列表中看到我的外围设备...即使可能这种方式没办法匹配,但这也是一个较小的问题。
我尝试过的方法:
1)我从example-gatt-server
Python代码中删除了具有安全/加密特性的TestService
,因此剩下的都是Heartrate
和Battery
服务。 iPhone的nRF Connect
应用程序仍在连接30-60秒后断开连接。
2)为了确定断开连接的原因,我查看了Linux中bluetooth.service
的日志:
Mar 15 18:44:57 sn0010 bluetoothd[775]: src/gatt-database.c:send_notification_to_device() GATT server sending notification
Mar 15 18:44:58 sn0010 bluetoothd[775]: src/adapter.c:dev_disconnected() Device MAC_ADDR_HERE disconnected, reason 1
Mar 15 18:44:58 sn0010 bluetoothd[775]: src/adapter.c:adapter_remove_connection()
Mar 15 18:44:58 sn0010 bluetoothd[775]: plugins/policy.c:disconnect_cb() reason 1
Mar 15 18:44:58 sn0010 bluetoothd[775]: src/adapter.c:bonding_attempt_complete() hci0 bdaddr MAC_ADDR_HERE type 1 status 0xe
Mar 15 18:44:58 sn0010 bluetoothd[775]: src/device.c:device_bonding_complete() bonding (nil) status 0x0e
Mar 15 18:44:58 sn0010 bluetoothd[775]: src/device.c:device_bonding_failed() status 14
Mar 15 18:44:58 sn0010 bluetoothd[775]: src/adapter.c:resume_discovery()
Mar 15 18:44:58 sn0010 bluetoothd[775]: src/device.c:att_disconnected_cb()
Mar 15 18:44:58 sn0010 bluetoothd[775]: src/device.c:att_disconnected_cb() Connection timed out (110)
Mar 15 18:44:58 sn0010 bluetoothd[775]: src/service.c:change_state() 0x20d080: device MAC_ADDR_HERE profile batt-profile state changed: connected -> disconnecting (0)
Mar 15 18:44:58 sn0010 bluetoothd[775]: src/service.c:change_state() 0x20d080: device MAC_ADDR_HERE profile batt-profile state changed: disconnecting -> disconnected (0)
Mar 15 18:44:58 sn0010 bluetoothd[775]: src/service.c:change_state() 0x20d638: device MAC_ADDR_HERE profile deviceinfo state changed: connected -> disconnecting (0)
Mar 15 18:44:58 sn0010 bluetoothd[775]: src/service.c:change_state() 0x20d638: device MAC_ADDR_HERE profile deviceinfo state changed: disconnecting -> disconnected (0)
Mar 15 18:44:58 sn0010 bluetoothd[775]: src/service.c:change_state() 0x20ca00: device MAC_ADDR_HERE profile gap-profile state changed: connected -> disconnecting (0)
Mar 15 18:44:58 sn0010 bluetoothd[775]: src/service.c:change_state() 0x20ca00: device MAC_ADDR_HERE profile gap-profile state changed: disconnecting -> disconnected (0)
Mar 15 18:44:58 sn0010 bluetoothd[775]: src/gatt-client.c:btd_gatt_client_disconnected() Device disconnected. Cleaning up.
Mar 15 18:44:58 sn0010 bluetoothd[775]: src/device.c:att_disconnected_cb() Automatic connection disabled
Mar 15 18:44:58 sn0010 bluetoothd[775]: attrib/gattrib.c:g_attrib_unref() 0x21e968: g_attrib_unref=0
Mar 15 18:44:58 sn0010 bluetoothd[775]: src/gatt-database.c:att_disconnected()
这似乎是说发生了超时(原因1)。
3) 我在Linux sysfs
中修改了默认的conn_min_interval=24
,conn_max_interval=40
和supervision_timeout=42
值以匹配苹果兼容性指南。(值被显式地更改为12
、24
和200
。)重启并重新启动蓝牙后,没有任何改变。
4) 我尝试在hciconfig hci0 leadv 0
之前输入btmgmt bredr off
和btmgmt bondable off
,但没有变化。
5) 我运行了nRF Sniffer
,但似乎没有捕获到断开事件。我可以通过过滤其BD地址来告诉我的周边正在广播,如下所示:
6) 我彻底禁用了example-gatt-server
。虽然nRF Connect
仍然能够连接,但在30-60秒后断开连接。这似乎将问题隔离在iOS应用程序、BlueZ堆栈或较低级别的Linux驱动程序层/配置内。
7) 使用nRF Connect
连接Android没有问题,可以保持稳定的连接。
问题
有没有人有关于接下来该尝试什么的建议?
编辑1:
根据评论,我在iPhone连接时在Linux主机上运行了btmon
。我启用了iPhone上的Heartrate
特征的notify
。日志显示由于超时而断开连接。
< ACL Data TX: Handle 128 flags 0x00 dlen 7 #4792 [hci0] 105.414362
ATT: Read Request (0x0a) len 2
Handle: 0x0016
> ACL Data RX: Handle 128 flags 0x02 dlen 9 #4793 [hci0] 105.466957
ATT: Error Response (0x01) len 4
Read Request (0x0a)
Handle: 0x0016
Error: Insufficient Authentication (0x05)
> HCI Event: Number of Completed Packets (0x13) plen 5 #4794 [hci0] 105.467019
Num handles: 1
Handle: 128
Count: 1
< ACL Data TX: Handle 128 flags 0x00 dlen 7 #4795 [hci0] 105.474721
ATT: Read Request (0x0a) len 2
Handle: 0x0016
< ACL Data TX: Handle 128 flags 0x00 dlen 11 #4796 [hci0] 105.564168
ATT: Handle Value Notification (0x1b) len 6
Handle: 0x000c
Data: 0e7d6400
< ACL Data TX: Handle 128 flags 0x00 dlen 9 #4797 [hci0] 106.558967
ATT: Handle Value Notification (0x1b) len 4
Handle: 0x000c
Data: 0665
> HCI Event: Number of Completed Packets (0x13) plen 5 #4798 [hci0] 106.877481
Num handles: 1
Handle: 128
Count: 3
> HCI Event: Disconnect Complete (0x05) plen 4 #4799 [hci0] 106.877698
Status: Success (0x00)
Handle: 128
Reason: Connection Timeout (0x08)
@ MGMT Event: Device Disconnected (0x000c) plen 8 {0x0001} [hci0] 106.877764
LE Address: 71:68:0B:72:0F:E9 (Resolvable)
Reason: Connection timeout (0x01)
@ MGMT Event: Device Disconnected (0x000c) plen 8 {0x0002} [hci0] 106.877764
LE Address: 71:68:0B:72:0F:E9 (Resolvable)
Reason: Connection timeout (0x01)