Input devices like keyboards, mice and trackballs are commonly known as Human Interface Devices (HID). These can be enabled by scanning for devices and then completing the pairing operation.
Enable the agent:
[bluetooth]# agent on
Instruct the agent to start a scan for devices:
[bluetooth]# scan on
Note: Some devices must be placed in pairing mode during the scan, oe they will not be found. Consult the device's documentation for pairing and “being found” guidance.
Provide the MAC address to pair:
[bluetooth]# pair <BT HID device MAC address>
Note: Some device will require a passkey submission
[agent] Passkey: 123456