Rockwell Automation 8520-MUM 9/Series CNC Mill Operation and Programming Manual Documentation Set - Manual (Page 795)

Chapter 30
Using a 9/Series Dual--processing System
30-27
Block Retrace
Any part program blocks prior to an axis process switch can not be
retraced. If you attempt to retrace beyond the point that an axis switch
occurred, the control generates an error. Also an axis process switch can
not be performed if you are currently performing a block retrace.
Scaling
Scaling is performed on a per process basis. If you switch processes for a
scaled axis, scaling is removed in the new process. Scaling is then
re-applied to the axis when it returns to the process in which scaling is
active for that axis. You can scale the shared axis by different amounts in
different processes.
Axis Inhibit, Axis Detach, and Servo Off
When you turn any of these three features on for a shared axis, it applies to
that axis in all processes. Control of that axis can be changed from one
process to another. However, the state of Axis Inhibit, Axis Detach, and
Servo Off remains constant from process to process.
Mirroring
There are two types of mirroring available:
Programmable Mirror Image (G50.1-G51.1) -- This type of mirroring is
performed on a per process basis. The shared axis is mirrored only in
the process requesting that axis be mirrored with a G51.1 block.
Manual Mirror Image -- This type of mirroring is performed on a per
axis basis. Manual mirroring is performed thru PAL or thru the front
panel softkey. Shared axes that are mirrored remain mirrored in all
processes as long as manual mirroring remains active.
Part Rotation
Both programmed coordinate system rotations (G68-G69) and external part
rotation are performed on a per process basis. Rotation is removed from a
shared axis when it changes process. The shared axis applies any rotation
that is active in the new process. Rotation remains active in a process that
is not controlling a shared axis however this rotation is not applied until
control of the shared axis is returned to the process.
Plane Selection
You can not activate a plane that contains a shared axis that is currently in
another process. You can however switch an axis that is in the currently
active plane over to a different process and still keep the plane active.
When the active plane contains a shared axis currently controlled by
another process, programming any plane dependent features (such as
circular interpolation) results in an error. The plane becomes available
when control of the shared axis is returned to the process.