Siemens SINUMERIK 840D sl Function Manual page 53

Example
"Multiple feedrates in one block" NC function
Entry in channel-specific machine data:
MD21220 $MC_MULTFEED_ASSIGN_FASTIN = 129
This activates various feedrate values as a function of the status of comparator byte 2.
Figure 1-5 Functional sequence for comparator input byte 1 (or 2)
Extended Functions
Function Manual, 01/2008, 6FC5397-1BP10-3BA0
Digital and analog NCK I/Os (A4)
1.2 NCK I/O via PLC
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