I think I may have found the source of the problem. While I had the web interface working I did home the axes. This left my Z endstop triggered which is pulling V to GND constantly it looks like. I'll have to fix this in the morning.
I am able to communicate if I disconnect the Z endstop. I may have to re-design my endstops to use all 3 pins? Or maybe I just have them configured wrong…
EDIT: I just saw your post. Yes, it does look like the same issue.
I had to re arrange the pins on my endstop to fix it. Mine are the "dumb" 2 wire endstops, and I connected the wires on the outside, leaving the middle blank. The polarity on it doesn't matter. 3 wire endstops are a little more confusing though.
edit: I can't spell