Me and 4 other buddies grouped up to each make our own custom mechanical keyboard. This is my 1st time doing a thing of the sort, and I haven't even looked into mechanical keyboards before this project.
So after a few months of planning and work, I have finally soldered everything together (to a teensy, following Matt3o the great's guide, building brownfox). I continued using his guide to programme the teensy, using Hasu's tmk, and using the g60 as a base model.
Link to Matt3o's guide I used to programme:
http://deskthority.net/workshop-f7/how- ... t7177.html
It all works. In fact, I am typing this post at the moment with this keyboard I built

But, there is a little thing I want to add to the keyboard. I have a toggling FN layer, and in order to know if this layer is toggled ON or OFF, I connected an LED to the FN key, and connected it to the GND and D4 pin on the teensy. Everything works, I connected it to the VCC and GND pins to check.
Now. To the point. I have searched the interwebs, and found nothing. Can any saint tell me how to activate the LED when press the FN key, and deactivate it when it is pressed again? (Basically outputting to a pin when the Fn is pressed)
Thanks a whole lot to any helper
