Please help with some arduino coding for throttle

[Gareth Barry]

Hi all

I'm hoping this is the correct place for this question- I am wanting to build my own throttle replica for the f14. I am at the point of coding and connection an arduino leonardo, and I would like to use to CD4021 shift registers daisy-chained together to handle the 15 buttons that I am going to need. I am having some trouble understanding the 'shiftin' function for arduino, and how to use it work with the joystick.h library in order to use the shift registers to handle the buttons.

I have found this tutorial;

CD4021B Shift Registers | Arduino Documentation

I am still struggling to make sense of how I would modify it to handle the buttons of the joystick.

Any help would be greatly appreciated.