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Name:	MACH3 Board Pic.JPG 
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Tha above is the board I have and am currently using to control my CNC router. Only problem is I want to use limit switches and homing switches and require three free input pins to do so. Three of the input pins are already in use for 1: Emergency Stop, 2: Probe 3: Drivers. This only leaves one input pin left which is not enough is there a work around? I have two spare board so is it possible to somehow use these to extend the number of input pins I have or ?