Siemens SINUMERIK 840D sl Function Manual page 15

2.1.2 Ready signals to PLC
DB10 DBX104.7 (NC-CPU-Ready)
The NC CPU is ready and registers itself cyclically with the PLC.
DB10 DBX108.1 (HMI-CPU2-Ready)
HMI CPU2 is ready and registers itself cyclically to NC.
References:
/FB2/ Function Manual, Expansion Functions; Several Control Panels on Multiple NCUs,
Decentralized Systems (B3)
DB10 DBX108.2 (HMI-CPU1-Ready, HMI an MPI)
The HMI CPU1 is ready and registers itself cyclically with the NC. Operator unit connection
via MPI interface.
DB10 DBX108.3 (HMI-CPU1-Ready, HMI at BTSS)
The HMI CPU1 is ready and registers itself cyclically with the NC. Operator unit connection
via OPI interface.
DB10 DBX108.6 (611D-Ready)
Group signal: All available SIMODRIVE 611D drives ready.
Condition: Readiness of all machine axes:
DB31, ... DBX93.5 (Drive Ready) = 1
611D Ready is only output in conjunction with SIMODRIVE 611D drives.
DB10 DBX108.7 (NC-Ready)
The NC is ready.
Basic logic functions: Various NC/PLC interface signals and functions (A2)
Function Manual, 11/2006, 6FC5397-0BP10-2BA0
Detailed description
2.1 NC/PLC interface signals
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