Thank you very much for the response; I did not realize that 'indicate' was exclusive to doing an attribute read. However, "notify on" doesn't seem to help. The device disconnects after a read and now I can no longer connect to it at all: QardioARM:/service0400/char0410]# notify on Notify started [CHG] Device 5C:D6:1F:0E:0A:7D ServicesResolved: no [CHG] Device 5C:D6:1F:0E:0A:7D Connected: no [bluetooth]# connect 5C:D6:1F:0E:0A:7D Attempting to connect to 5C:D6:1F:0E:0A:7D Failed to connect: org.bluez.Error.Failed On the bluetoothd side I'm seeing: bluetoothd[20426]: src/agent.c:agent_disconnect() Agent :1.626 disconnected bluetoothd[20426]: src/agent.c:remove_default_agent() Default agent cleared bluetoothd[20426]: src/adapter.c:set_mode() sending set mode command for index 0 bluetoothd[20426]: src/agent.c:agent_destroy() agent :1.626 bluetoothd[20426]: src/agent.c:agent_unref() 0x55e718787df0: ref=0 bluetoothd[20426]: src/adapter.c:new_settings_callback() Settings: 0x00000a01 bluetoothd[20426]: src/adapter.c:settings_changed() Changed settings: 0x00000010 bluetoothd[20426]: src/adapter.c:settings_changed() Pending settings: 0x00000000 bluetoothd[20426]: src/agent.c:add_default_agent() Default agent set to :1.627 /org/bluez/agent bluetoothd[20426]: src/adapter.c:set_mode() sending set mode command for index 0 bluetoothd[20426]: src/agent.c:agent_ref() 0x55e7187b7a00: ref=1 bluetoothd[20426]: src/agent.c:register_agent() agent :1.627 bluetoothd[20426]: src/adapter.c:new_settings_callback() Settings: 0x00000a11 bluetoothd[20426]: src/adapter.c:settings_changed() Changed settings: 0x00000010 bluetoothd[20426]: src/adapter.c:settings_changed() Pending settings: 0x00000000 bluetoothd[20426]: src/device.c:att_connect_cb() connect error: Connection refused (111) I should note that I've tried a number of BTLE blood pressure devices with a variety of BT controllers and Bluez cannot seem to maintain reliable connections with any of the configurations I've tried. Any help would be much appreciated. On Thu, Jan 2, 2020 at 7:30 PM Luiz Augusto von Dentz <luiz.dentz@xxxxxxxxx> wrote: > > Hi Peter, > > On Thu, Jan 2, 2020 at 5:22 PM Peter Belau <pbelau1@xxxxxxxxx> wrote: > > > > I'm trying to get a Qardio ARM BP monitor working with Linux/Bluez but > > cannot seem to read any device characteristics with Bluez. My > > interaction through bluetoothctl looks like this: > > > > # menu gatt > > # attribute-info 00002a35-0000-1000-8000-00805f9b34fb > > Characteristic - Blood Pressure Measurement > > UUID: 00002a35-0000-1000-8000-00805f9b34fb > > Service: /org/bluez/hci0/dev_B0_49_5F_02_B5_61/service0400 > > Value: > > 16 7f 00 49 00 5b 00 00 00 00 00 00 00 00 35 00 ...I.[........5. > > 00 00 .. > > Notifying: no > > Flags: indicate > > # select-attribute 00002a35-0000-1000-8000-00805f9b34fb > > # read > > # Attempting to read /org/bluez/hci0/dev_B0_49_5F_02_B5_61/service0400/char0410 > > Failed to read: org.bluez.Error.Failed > > > > I have bluetoothd running with debug flags but nothing appears in the > > debug logs. What am I doing wrong? > > Look at the flags, it only has indicate so it doesn't support reading directly. > > -- > Luiz Augusto von Dentz
