Siemens SINUMERIK 840D sl Function Manual page 51

● Inversion mask for output of the comparator input byte (bits 24 ... 31)
For every comparator signal it is also possible to define whether the signal state to be output
at the digital NCK output is to be inverted or not.
Threshold values
The threshold values used for comparisons on comparator byte 1 or 2 must be stored as setting
data. A separate threshold value must be entered for each comparator input bit <b> (with <b>
= 0 ... 7):
SD41600 $SN_COMPAR_THRESHOLD_1[<b>]
or
SD41601 $SN_COMPAR_THRESHOLD_2[<b>]
Comparator signals as digital NCK inputs
All NC functions that are processed as a function of digital NCK inputs can also be controlled
by the signal states of the comparators. The byte address for comparator byte 1 (HW byte 128)
or 2 (HW byte 129) must be entered in the machine data associated with the NC function
("Assignment of hardware byte used").
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.
Extended Functions
Function Manual, 10/2015, 6FC5397-1BP40-5BA3
Byte = 0: No output via digital NCK outputs
Byte = 1: Output via digital on-board-NCK outputs 9 ... 16
Byte = 2: Output via external digital NCK outputs 17 ... 24
Byte = 3: Output via external digital NCK outputs 25 ... 32
Byte = 4: Output via external digital NCK outputs 33 ... 40
Bit = 1: Associated comparator input bit is not inverted.
Bit = 0: Associated comparator input bit is inverted.
A4: Digital and analog NC I/O for SINUMERIK 840D sl
2.2 Indirect I/O access via PLC
51