Rockwell Automation 8520-MUM 9/Series CNC Mill Operation and Programming Manual Documentation Set - Manual (Page 640)

Milling Fixed Cycles
Chapter 26
26-8
Important: After programming a milling fixed cycle block, parameters X,
Y, Z and R can be programmed in later blocks with different values. This,
of course, permits axis motion to be changed. Parameters Q, P, I and K can
only be programmed in the calling block for the milling fixed cycle. They
cannot be programmed following the calling block. If they are, the control
will ignore them.
This section describes how the control executes each milling fixed cycle.
The following is assumed for each cycle:
initial point level is the return level (G98 is active)
incremental mode is active (G91 is active)
the X and Y axes are the positioning axes
the Z axis is the hole machining axis
The milling fixed cycles are modal, which means they remain active until a
G--code that cancels the milling fixed cycle is programmed. A milling
fixed cycle can, therefore, be repeated at different positions, without
having to re-program all the parameters associated with a given operation.
CAUTION: The controlling spindle code determines which
spindle and its related spindle M-codes (modal) will be active
during milling cycles. When spindle is mentioned in relation to
milling fixed cycles, we are referring to the controlling spindle.
For more information on controlling spindles, refer to chapter 17.
Similarly, any parameters specified in the block with the G--code of the
milling fixed cycle remain active until the cycle is cancelled, or until they
are programmed again in a following block. L--words do not remain active
and, instead, are active only for the block which contains the actual
L--word.
G00, G01, G02, and G80 will cancel milling fixed cycle modes.
26.4
Milling Fixed Cycle
Operations