Rockwell Automation 8520 9/Series CNC Integration Maintenance Manual Documentation Set - Manual (Page 611)

Section 11A
Connecting 1394 Digital Drive Systems
11A-6
Each of these CNCx connectors on the CNC interface board corresponds to
the motor and feedback device (if the feedback is wired to the CNC wiring
board correctly) of the axis module (x). For example CNC1 is used for
axis module 1 and FB0. CNC2 is for axis module2 and FB1. Ultimately
the connector and feedback combinations you decide to use for each axis is
configured in AMP however we recommend the following configuration:
Axis Number CNC Interface
Board
Four Axis
1394 Digital
Servo Card
1394 Digital
9/230 CNC
1 CNC 1 J1 J1
2 CNC 2 J2 J2
3 CNC 3 J3 J3
4 CNC 4 J4 N/A