Siemens SINUMERIK 840D sl Function Manual page 43

Fast analog NCK inputs
The fast analog inputs must be isochronous. The assignment is defined by the machine data:
MD10384 $MN_HW_CLOCKED_MODULE_MASK
Figure 1-3
Extended Functions
Function Manual, 03/2009, 6FC5397-1BP10-4BA0
Signal flow for analog NCK inputs
Digital and Analog NCK I/Os (A4)
NCK I/O via PLC
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