Remapping "Fn" on a MacBook

[Hon Leung]

Context:

Got a MacBook Pro Early-2013 i7-3820QM 16GB GT650M 1GB [MacBookPro10,1] for CAD $600 earlier last year (not a bad deal)

Been using Windows via Bootcamp and its great, except that the Fn key is where Ctrl key should be on a Windows laptop.

 

Trying to Achieve:

Under Bootcamp Windows, use my Fn key as Ctrl key, or in other words, map my Ctrl key onto Fn key. Swapping them would be even better.

(same thing is achieved under macOS with special key mappings by tweaking Keyboard Preferences)

 

Solutions that dont seem to work:

- Use Windows key remapping tools - AutoHotKey and SharpKeys don't work because Fn key is not processed through the registry, likely for other apps as well

- Tweaking the MacBook BIOS - MacBooks dont have BIOS, only something in place of a BIOS that doesn't offer this option

- Tweaking the BIOS/UEFI responsible for Windows - Bootcamp Windows seem to run using a pseudo-BIOS layer on top of MacBook's own BIOS-thing, which is inaccessible (this is also responsible for disabled integrated graphics)

- Non-Bootcamp Windows - many other devices cannot communicate with Windows without macOS Bootcamp setting them up via the pseudo-BIOS, not worth the drawback, also the Fn key is not recognized

 

Solutions that could work:

- Patching kexts to rewrite the keyboard driver - not sure how to do it, risky cos I already patched a lot of things to make my MacBook Pro run Big Sur unsupported

- Write an extension to the Windows Bootcamp tool thingy - not sure how to do it, but as this service seem to directly speak to the pseudo-BIOS it may work, butttt Apple definitely would not have that option easily accessible

 

Unaccepted Solutions:

- Rewiring/Resoldering the keys on the keyboard by opening it up - too risky to mess something up, not worth it

- Get used to it - this is just my programming laptop, I use Windows for design and gaming so I dont want my muscle memory messed up

- Use an external keyboard - portability compromised

- Just use macOS - Windows file management is more efficient and I prefer using it when I manage files

- Just use a Windows laptop - I am basic and I dont like it (for coding)

- Rewire the keyboard to a hidden raspberry pi that sends keyboard outputs as inputs to the actual laptop - no im not even sure how I thought of that

 

Current Solution:

I sliced and rounded a thin black metal plate to cover up both the Fn and Ctrl keys, so if i press in the middle it presses both of them, and I can press on the side to trigger one of them - not good enough cos I want the leftmost key pressed to be Ctrl and the keys are elevated.

 

Please offer your solution if you can think of something.