Siemens SINUMERIK Series Function Manual page 853

Bit signals
DB19
DBX 126.0
Data Block
Edge evaluation: No
Signal state 1 or
edge change
0 → 1
Signal state 0 or
edge change
1 → 0
DB19
DBX 126.1
Data Block
Edge evaluation: No
Signal state 1 or
edge change
0 → 1
Signal state 0 or
edge change
1 → 0
DB19
DBX 126.2
Data Block
Edge evaluation: No
Signal state 1 or
edge change
0 → 1
Signal state 0 or
edge change
1 → 0
Extended Functions
Function Manual, 03/2013, 6FC5397-1BP40-3BA1
MMC1_SHIFT_LOCK
Disable/enable control unit switchover
Signal(s) updated: Cyclic
Control unit switchover or change in operating focus is disabled.
The current control unit-NCU constellation remains unchanged.
Control unit switchover or change in operating focus is enabled
MMC1_MSTT_SHIFT_LOCK
Disable/enable MCP switchover
Signal(s) updated: Cyclic
MCP switchover is disabled.
The current MCP-NCU constellation remains unchanged.
MCP switchover is enabled
MMC1_ACTIVE_REQ
Control unit 1 requests active operating mode
Signal(s) updated: Cyclic
HMI to PLC: passive control unit 1 requests active operating mode
PLC to HMI: Request received
Z2: NC/PLC interface signals
18.2 Distributed systems (B3)
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