I see that Mach 3 has Modbus capabilities. Does anyone know how difficult it would be to interface a PC running Mach 3 with an Automation Direct GS-2 drive using the modbus protocol over RS-232 or 485? I was originally looking to use another CNC controller program (CNC Zeus) mainly because it was capable of directly controlling my spindle without additional hardware, but I have not been thrilled with the performance, and Mach 3 looks like it might work well, provided I can control my spindle with it.