F13 to F24: Spare Keys for Macropad Bindings

KM16 Macropad provides sixteen keycaps, one large knob and two small knobs on anodised aluminium. Its confirmed VIA remapping can turn physical positions into higher function-key outputs that are uncommon on modern keyboards.

What are F13 through F24?

They are keyboard function-key codes beyond the familiar F1 to F12 row. Operating systems and remapping tools can recognize many of them even when the main keyboard has no labelled key for them. Microsoft, for example, explicitly lists F13 through F24 as mappable in PowerToys Keyboard Manager.

Their absence from most physical layouts does not make them magical or universally free. Applications, remote desktops and accessibility tools can already assign meanings to higher function keys. Treat them as low-collision candidates, not a guaranteed private channel.

Why are higher function keys useful for macropads?

If a pad emits a letter or common shortcut, an operating-system remap may also affect the main keyboard. F13 gives the pad a distinguishable logical output without consuming a familiar typing key. The receiving editor or automation tool can then assign the actual command.

This creates two inspectable layers: hardware output and application action. When a shortcut fails, test the higher function key first and the target binding second. Keep a table of physical position, VIA output and final command instead of relying on keycap labels alone.

How do you send them from a VIA-remappable pad?

Connect the device by USB, open the current VIA interface and select one key position. If the connected firmware exposes the desired higher function key, assign it and test the result before changing another position. VIA can only offer the keycodes and controls supported by that firmware and definition.

Do not flash firmware from a similar-looking board to add a missing option. A mismatched build can use a different matrix or bootloader. Preserve the starting layout and power-cycle the pad to confirm that the chosen output remains available.

Do every operating system and app recognise them?

No. Windows utilities and many desktop applications accept higher function keys, while macOS and Linux remappers may expose them under their own key names or HID usages. A browser, virtual machine or remote session can intercept or discard the event. Test in the exact path where it will be used.

The KM16 Macropad has more positions than this technique needs. Begin with F13, confirm it in an event viewer on the destination system and bind one harmless action. Add the remaining codes only after checking for existing system and application shortcuts. Reserve a normal keyboard route to the same action until the complete input path has proved stable.