I not finding any information on the D12 - PS-ON terminal. I'm guessing this is for power supply on/off control?
Can it be hooked up to a PC Power Supply to turn it on and off?
Ahh, tie the green wire from the ATX power supply to the PS-ON terminal on the ramps board so that the PC can send M80 to turn the power on.
Cool, works great.
Hook it up to the green wire on the ATX connector. Check whether your firmware supports this first. IF not, just short the green to a black wire and the PSU will always run when powered.