I have a Gecko G540 to drive the bipolar X, Y and C axis (head rotation). The two Z-axis and additional tape index probe I have been planning to design a Modbus board to drive them, as well as anything else that needed specific control (paste dispension etc...). My intention has been to look as customising Mach3 to suit the application, as I haven't found any other software I could use. Which software do you use Chris?