archlinux 连接 蓝牙键盘
filco 配对 ctrl+alt+fn
忘记已配对设备 connect 长按3秒
#mac of bluetooth keyboard
# 00:18:00:3C:A4:C5
bluetoothctl
# show help info
help
# show keyboard info, paired, trusted, connected
info 00:18:00:3C:A4:C5
power on
devices
agent on
pair 00:18:00:3C:A4:C5
trust 00:18:00:3C:A4:C5
connect 00:18:00:3C:A4:C5
systemctl start bluetooth