Hey kb0nly,

I don't know if you're still on here, but I had questions about the PWM-OUT port. Are you suggesting that the pins are as follows?

1 - PWM Output -> connected to the collector of ENO optocoupler. Anode pin for this optocoupler is cut on some boards (not mine). Connected to the A-axis.
2 - External voltage -> emitter for DDO?
3 - GND -> collector for DDO?
4 - Spindle ON/OFF output -> Q for DDO?

It seems like with the mod, both the physical switch and the software switch must be on at the same time right? Also, it seems like PWM Output could not be enabled without interfering with the A-axis. In this case, would it be possible to output a PWM signal on pins 2-3 instead? That way, the spindle would have to be turned on using the physical button, but then the speed could be controlled by software and *effectively* turn off by decreasing the speed to 0.

Thanks!