Heated Build Platform Controller V0.2

I really wanted a fully integrated solution for controlling a heated build platform, as well as for communicating with the motherboard. I also wanted to be able to use the heated build platform as a controlled hot plate in order to do surface mount reflow. I created this board to have the ability to do both. I started this several months ago, but just now was able to gather all of the parts to build it and test it.

The board is meant to control mains voltage (i.e. 120/240 VAC), and therefore