First off, functional information on the machine.
ESS Smoothstepper
C11G for controls
DMM Servos and drivers
2 motors driving y axis gantry, single motor running x axis and another running z.
So here's the issue, I need more inputs so I got a C25S board. I changed the port the C11G was plugged into from port1 of the ESS board to port3. I then changed the pinout and all details in Mach4 to reflect the change of port.
Here's where it gets a bit odd, the slave motor on the y axis starts moving just a brief pace behind the master when moving the y axis, bad enough that it faults out the drivers on occasion.
I've set things back as they were and reloaded my backup from before I made any changes. All back to normal now.
Any ideas on what to look at that I may have missed?