Siemens SINUMERIK 840D sl Function Manual page 40

A4: Digital and analog NC I/O for SINUMERIK 840D sl
2.2 Indirect I/O access via PLC
Special cases
● If several output bits are assigned to the same input bit, then the one with the highest MD
index becomes effective.
● If inputs or outputs are specified which do not exist or are not activated, then the assignment
is ignored without an alarm. Checking of the active bytes of the NC I/Os is performed via
the entries in machine data:
MD10350 $MN_FASTIO_DIG_NUM_INPUTS
MD10360 $MN_FASTIO_DIG_NUM_OUTPUTS
Defining assignments
The assignments are specified via machine data:
MD10361 $MN_FASTIO_DIG_SHORT_CIRCUIT[n]
n: can accept values 0 to 9, so up to 10 assignments can be specified.
Two hexadecimal characters are provided for specifying the byte and bit of an output and an
input.
Specifying 0, A and B in input bits 12 - 15 results in the following logic operations:
0
A
B
Examples
Connect:
MD10361 $MN_FASTIO_DIG_SHORT_CIRCUIT = '04010302H'
Output 4, byte 1, connect to
Input 3, byte 2
AND operation:
MD10361 $MN_FASTIO_DIG_SHORT_CIRCUIT = '0705A201H'
Output 7, byte 5 AND operation with
Input 2, byte 1
OR operation:
40
Connecting
AND operation
OR operation
Function Manual, 10/2015, 6FC5397-1BP40-5BA3
Extended Functions