I am trying to design some modules which are meant to drive a stepper each using the L293NE driver IC from TI. The design drives the stepper based on the results of sensor inputs, ie. pushbutton and IR rangers. The design is intended to be modular in nature, and needs to be able to communicate with as many or as few modules in the specific application. The questions are...1 how many pins(to and from uC) minimally am I going to need to make this work with all desired functions?2 How to interlink each module for communication with eachother, keeping in mind that there could be as many as 10 modules or as few as two in any given implementation.