Siemens SINUMERIK 840D sl Function Manual page 1249

2.13 Signal/data descriptions
2.13.1 Interface signals NCK/PLC, MMC/PLC, MCP/PLC
General
The NCK/PLC, HMI/PLC, and MSTT/PLC interface signals are listed in the Parameter
Manual for SINUMERIK 840D with references to the respective function description where
the signals are described.
References:
/LIS2/ Lists (Volume 2)
The NCK signals that are evaluated by the basic program and transferred in conditioned
form to the user interface are presented in the following sections.
2.13.2 Decoded M signals
General
The M functions programmed in the part program, ASUB or synchronized actions are
channel specifically transferred from the NC to the PLC:
• M functions from channel 1: DB21
• M functions from channel 2: DB22
• etc.
The signal length is one PLC cycle.
Note
The spindle-specific M functions below are not decoded: M3, M4, M5, and M70.
Basic logic functions: PLC Basic program powerline (P3 pl)
Function Manual, 11/2006, 6FC5397-0BP10-2BA0
Detailed description
2.13 Signal/data descriptions
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