I have a Sunwin TB6560 "all-in-one" controller board that runs through my computer's USB port (I bought it before I knew how "bad" TB6560 boards are supposed to be; this one seems to work fine upon testing, though, so we shall see.) Here is a link to the board I have (no, I didn't get it from Aliexpress; it was cheaper on EBay and at least I'd have buyer protection...): Aliexpress.com : Buy Free shipping 4 Axis Nema23 3.0A Stepper Motor USB Driver Board, TB6560 USB CNC DIY Controller from Reliable driver board suppliers on SUNWIN. Software is CNC-USB from Planet CNC. It is supposed to be able to support two limit switches per axis, though I don't see how I will be putting a limit switch on my rotary table once I convert it. What I am wondering, though, is where I might install an e-stop switch? I have an e-stop switch on my Sieg X2, but that only shuts the spindle down; it won't stop the stepper motor movement.