I would like to be able to control multiple relays, perhaps 3 or 4 to turn on and off different devices I have within my machine (such as LEDs, lamps, DC motors, etc.) The relays only require a 5V logic HIGH or LOW. Are there any open pins that I can pull from and toggle on and off with GCODE commands?
I have an MPCNC and spindle setup. Currently, to toggle the relay for the spindle I use M106 to toggle the D9 terminal on the Ramps board. I cannot seem to understand how to access any other switchable pins.
Any help would be appreciated.