Rockwell Automation 8520-ARM2 9/Series CNC AMP Reference Manual Documentation Set - Manual (Page 444)

Power-up G-code Parameters
Chapter 19
19-12
Function
This parameter selects the default G-code for modal group 17.
This parameter is available for grinder applications only.
If this parameter is set to: the spindle is:
ON under CSS control
OFF in the RPM spindle speed mode
Axis Parameter
Number
All [21]
Range
Selection Result
(a) On
(b) Off
Notes
This is a global parameter; the value set here applies to all axes.
19.11
CSS (On/Off)