RGB Encoder Breakout - Register Map (Seeeduino Xiao)

Hi,

I’ve just got this : https://shop.pimoroni.com/products/rgb-encoder-breakout
(An RGB encoder breakout board.)

I’m using it with a Seeeduino Xiao, so unfortunately the on-line examples don’t quite match up. So I’m starting from scratch. Unfortunately it seems to be missing some key documentation:

Would anyone have a Register Map, as per the example below?

Thanks!