This article describes how to set up a Bluetooth HID keyboard with Arch Linux, version 5.
Login to the affected computer by a wired keyboard or by ssh.
First, make sure the local BT controller (e.g. a BT dongle the built in BT radio) is recognized:
Bus 001 Device 004: ID 0a12:0001 Cambridge Silicon Radio, Ltd Bluetooth Dongle (HCI mode) Bus 001 Device 003: ID 0424:ec00 Standard Microsystems Corp. SMSC9512/9514 Fast Ethernet Adapter Bus 001 Device 002: ID 0424:9512 Standard Microsystems Corp. LAN9500 Ethernet 10/100 Adapter / SMSC9512/9514 Hub Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
The above output is from a Raspberry-Pi revision 'B' with archlinux-arm and a Keysonic BT Dongle.
Three items worth remembering:
- BT devices (keyboard) and controllers (dongle) need to be paired once.
- The BT controller needs to be powered up after every boot.
- The BT controller needs to be told to connect to the keyboard after every boot.
Pairing is a one time process, required only once. There are BT keyboards sold with a BT dongle which come already paired, but that's not certain. We will use the
bluetoothctl command from to pair our dongle and the keyboard.
Power up can be done with
bluetoothctl, or automatically in
/etc/bluetooth/main.conf, see below.
Same for connecting, either
hcitool can be used, the latter is more useful for scripting.
We will use
bluetoothctl for the pairing process. Run the command to get at the
While in bluetoothctl power up the controller:
[bluetooth]# power on
Changing power on succeeded [CHG] Controller 06:05:04:03:02:01 Powered: yes
bluetoothctl to look only for keyboards, and make that the default agent:
[bluetooth]# agent KeyboardOnly
Default agent request successful
Next, put your controller (the local dongle) in pairable mode:
[bluetooth]# pairable on
Changing pairable on succeeded
Next, put your keyboard in an active mode, where it is discoverable, i.e. pairable. Some keyboards have a special button for this on the underside, or require a special key combination to be pressed. See the documentation of your keyboard. Please note that this discoverability of a device is time limited, some devices are only visible 30 seconds, other for 2 minutes. Your mileage may vary.
Next, let the controller scan the BT frequencies for a suitable device:
[bluetooth]# scan on
Discovery started [CHG] Controller 06:05:04:03:02:01 Discovering: yes
After a few seconds the adress of the keyboard should be listed as found. This line will repeat over and over, but won't stop you from entering new commands.
Next, actually do the pairing. The address used is the BT-MAC address of the keyboard:
[bluetooth]# pair 01:02:03:04:05:06
Next, make this a trusted device (this allows the device to establish the connection on itself). Again, the BT-MAC address is the address of the keyboard device:
[bluetooth]# trust 01:02:03:04:05:06
Next and finally connect to the device (keyboard). Again, the BT-MAC address is the address of the keyboard device:
[bluetooth]# connect 01:02:03:04:05:06
Done. Leave the
Now the external device (i.e. keyboard) and the USB BT dongle are paired permanently, unless you break the pairing intentionally. This does not mean that the keyboard will connect automatically to your BT device after a boot. This is mainly due to the fact that the bluetooth controller will be automatically turned off after each reboot. To automatically connect the keyboard after a reboot, see Bluetooth#Auto power-on after boot.
What if the BT controller does not show up in
- Load generic bluetooth driver:
# modprobe btusb
- Is it an USB adapter or integral to the system? Use
lspcifor integral adapters
What if the BT controller is not visible in
systemctl status bluetooth
- Check: You run the command with superuser privileges using
sudo. Otherwise you have blue [bluetooth]# prompt and get the following message when powering on the controller:
[bluetooth]# power on No default controller available
My BT keyboard still does not work. What to do?
- Check: Does it have power?
- Check: Did it connect to the BT controller? If not, try with another controller or your smart phone.
All went fine but when I type I'm getting "Bluetooth: hci0 ACL packet for unknown connection handle 4"
- Try reset: hciconfig hci0 reset
Device should be added as
/dev/input/event* and your Xorg should add it automatically if you did not disable such feature.