Part 1 Arduino, inexpensive DRO. Digital Read Out. RF30 CNC Arduino conversion

I've done a CNC conversion to my RF30 mill. I still want to be able to use it manually. Easy enough on X &Y. I just made new dials to suit the 5mm pitch ball screws. On Z I needed a low cost, easy to fit DRO. I didn't want to use a digital callipers, so adapted a DRO from UA-cam. I'll add a link to the original video later.
I got the original idea from "Practice makes better" • Build your own DRO wit...

[@kevracer3980]

I got my original idea from "Practice makes better" ua-cam.com/video/Ru7ZCAhxA_8/v-deo.html