@Frank_Herrmann Arduino can be control with can bus and Mach3 has can support. Using a can shield allows all kinds of IO. The Arduino Due has onboard can support.
@mark_hubrich what do you mean with “has CAN support”?
It’s not like there are M-Codes to send arbitrary CAN messages to arbitrary bus-addresses.
@Marcus_Wolschon I’m sorry I totally got that wrong. It’s Modbus I meant to say. Here’s the details… http://www.machsupport.com/Mach3Wiki/index.php?title=Modbus_in_Mach