Syncup Operating State; Run Operating States - Siemens SIMATIC S7-1500 System Manual

The primary CPU establishes connections to the IO devices in the STOP operating state. The
primary CPU activates the system IP address even in the STOP operating state if the system IP
address has been configured.
If both CPUs are in STOP and you download a configuration to one CPU, note the following:
• You have not downloaded a configuration to the backup CPU and the backup CPU should
become the primary CPU:
Switch the backup CPU to the primary CPU (either in the event dialog of the download
process or via the mode switch of the CPU).
• Downloading to the primary CPU configures the connected IO devices in line with the
downloaded hardware configuration, even in STOP operating state.
11.4.4

SYNCUP operating state

SYNCUP operating state (only in the backup CPU)
In the SYNCUP operating state, the operating system synchronizes the backup CPU with the
primary CPU. The primary CPU is in the RUN-Syncup operating state and controls the process.
Unlike the primary CPU, the backup CPU does not go through the STARTUP operating state.
You can find more information in the section SYNCUP system state (Page 270).
Points to note
You have only limited access to online functions during SYNCUP. You can find more
information in the section Test functions (Page 344).
11.4.5

RUN operating states

RUN operating states
The primary CPU goes through multiple operating states before reaching the RUN-Redundant
system state:
• RUN
• RUN-Syncup
• RUN-Redundant
The backup CPU only has the RUN-Redundant operating state.
Response
In the RUN operating state, the primary CPU behaves just like an S7-1500 standard CPU. It
performs cyclic, time-driven and interrupt-driven program execution on its own.
Addresses that are in the "Automatic update" process image are automatically updated in
each program cycle. You can find more information in the section Process images and process
image partitions (Page 212).
Once the CPU has written the outputs and read the inputs, it runs through the cyclic program
from the first instruction to the last instruction. Events with a higher priority such as
S7-1500R/H redundant system
System Manual, 11/2022, A5E41814787-AD
Commissioning
11.4 Operating and system states
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