Glowing iBall

The other thing this mouse is missing is a scrolling capability. Since I've been using it as my daily driver I've noticed that I really do miss that ability, and it would be great to be able to hold a modifier key and scroll with the wheel. I was going to put a microcontroller in there to control the LEDs already, so now I'm considering making a new board entirely so that I can read the positional encoding wheel and assign a modifier key. This project is growing. 

Today I learned about How Computer Mice Work and visited the linked article about directional detection, so I thought my new understanding of transmissive optical sensors would help me find replacement parts to solder onto a new board. Instead I discovered that no one seems to make the kind that came out in 1998, and so a drop-in replacement that uses the same wheels that came with the iBall may be asking too much. 

What will happen next? Will I be able to find a sourceable optical sensor to use with the existing wheel, or will I have to get a new wheel assembly? Will I keep the original components from the iBall and swap them to the new PCB? How will I even read the data once I get it? Stay tuned for more adventures in quadrature.

I had to open it up and drop some sort of LED in there to see if the effect was going to be worth doing. The answer is that of course it will be worth it, and the proof of concept with a single color changing LED and a 2032 battery is what you see below.