Siemens Sinumerik 840D sl Programming Manual page 343

References:
Function Manual, Synchronized Actions
Grouping
The functions described can be grouped together. Group assignment is predefined for some
M commands. The acknowledgment behavior can be defined by the grouping.
High-speed function outputs (QU)
Functions, which have not been programmed as high-speed outputs, can be defined as high-
speed outputs for individual outputs with the keyword QU. Program execution continues without
waiting for the acknowledgment of the miscellaneous function (the program waits for the
transport acknowledgment). This helps avoid unnecessary hold points and interruptions to
traversing movements.
Note
The appropriate machine data must be set for the "High-speed function outputs" function
(→ machine manufacturer).
Function outputs for travel commands
The transfer of information as well as waiting for the appropriate response takes time and
therefore influences the traversing movements.
High-speed acknowledgment without block change delay
Block change behavior can be influenced by machine data. When the "without block change
delay" setting is selected, the system response with respect to high-speed auxiliary functions
is as follows:
Auxiliary function output
Before the movement
During the movement
After the movement
Fundamentals
Programming Manual, 01/2015, 6FC5398-1BP40-5BA2
Response
The block transition between blocks with high-speed auxiliary functions
occurs without interruption and without a reduction in velocity. The auxiliary
function output takes place in the first interpolator clock cycle of the block.
The following block is executed with no acknowledgment delay.
The block transition between blocks with high-speed auxiliary functions
occurs without interruption and without a reduction in velocity. The auxiliary
function output takes place during the block. The following block is execu‐
ted with no acknowledgment delay.
The movement stops at the end of the block. The auxiliary function output
takes place at the end of the block. The following block is executed with
no acknowledgment delay.
Auxiliary function outputs
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