Nck Digital Inputs/Outputs; Nck Digital Inputs - Siemens SINUMERIK 840D sl Function Manual

1.2.2

NCK digital inputs/outputs

1.2.2.1

NCK digital inputs

Number
General machine data is used to define available digital NCK inputs (in groups of 8).
MD10350 $MN_FASTIO_DIG_NUM_INPUTS
(Number of active digital NCK input bytes)
Function
The digital NCK inputs allow external signals to be injected which can then be used, for
example, to control the workpiece-machining program sequence.
The signal state of digital input [n] can be scanned directly in the part program using system
variable $A_IN[n].
The signal state at the hardware input can be changed by the PLC user program (see fig.).
Disable input
The digital NCK inputs can be disabled individually from the PLC application program with
the following interface signals:
DB10 DBB0 or DBB122 ... (Disabling of digital NCK inputs)
In this case, they are set to "0" in a defined manner inside the control.
Set input from PLC
The PLC can also use the following interface signal to set each digital input to a defined
"1" signal (see figure):
DB10 DBB1 or DBB123 ... (PLC setting of digital NCK inputs)
As soon as this interface signal is set to "1", the signal state at the hardware input or the
input disable is inactive.
Read actual value
The signal state of the digital NCK inputs is sent to the PLC:
DB10, DBB60 or DBB186 ... (actual value for digital NCK inputs)
The actual value reflects the actual state of the signal at the hardware input. The influence of
the PLC is, therefore, ignored in the actual value (see fig.).
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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