Siemens SINUMERIK 840D sl Function Manual page 1760

Detailed description
2.3 Feedrate control
Priorities
The signals are scanned in ascending order starting at I0.
Therefore, the retraction motion (SR) has the highest priority and the feedrate F7 the lowest
priority.
SR and ST end the feedrate motions that were activated with F2 - F7.
SR also ends ST, i.e., the complete function.
The highest-priority signal determines the current feedrate.
Machine data:
MD21230 MULTFEED_STORE_MASK
(store input signals for the "Multiple feedrates in one block" function)
can be used to define the response on loss of the highest-priority input in each case (F2 -
F7).
The endofblock criterion is satisfied when:
• The programmed end position is reached
• The retraction motion ends (SR)
• The dwell time elapses (ST)
Delete distance-to-go
A retraction motion or dwell time causes the distancetogo to be deleted.
Hardware assignment
The channel-specific machine data:
MD21220 MULTFEED_ASSIGN_FASTIN
(assignment of the input byte of the NCK I/Os for "Multiple feedrates in one block")
can be used to assign up to two digital input bytes or comparator input bytes to the NCK I/O.
Machine data:
MD21220 MULTFEED_ASSIGN_FASTIN
can also be used to invert the input bits.
If a 2nd byte is entered, the contents of the 1st and 2nd byte are ORed before being used.
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Basic logic functions: Feeds (V1)
Function Manual, 11/2006, 6FC5397-0BP10-2BA0