This document describes how to set default values on Bluetooth bind for the Apple Bluetooth Keyboard, such as disabling the fnmode to address certain key mapping issues.

On recent Debian operating systems, like Debian 12 Bookworm, the Apple Bluetooth Keyboard generally connects without issue. However, certain keys (e.g., 'j', 'k', 'l') may function as a number pad instead of producing letter characters, akin to having Num Lock activated.

Disabling fnmode by setting it to 0 resolves this key behavior anomaly.

Other solutions are available on the Arch Linux wiki at Apple Keyboard on ArchWiki. However, this solution primarily pertain to the MATE desktop environment on Debian, where the standard intramfs setup requires no modifications.

This approach avoids the use of modprobe and offers a simple, immediately reversible solution if changes need to be adjusted dynamically.

# As root
mkdir -p /opt/apple-bluetooth-keyboard
chown $USER:$GROUP /opt/apple-bluetooth-keyboard
# As $USER
cd /opt
git clone https://github.com/ckuelker/apple-bluetooth-keyboard.git
# As root
cd /opt/apple-bluetooth-keyboard/etc/udev/rules.d/
cp 90-apple-bluetooth-keyboard.rules /etc/udev/rules.d/
udevadm control --reload-rules

Utilize the Ansible role available at https://github.com/ckuelker/ansible-role-apple-bluetooth-keyboard to install and activate the udev rule.