Run" Mode - Siemens SIMATIC S7-1500 Automation System System Manual

8.4.4

"RUN" mode

Function
In "RUN" mode the cyclic, time-driven, and interrupt-driven program execution is performed.
Addresses that are in the "Automatic Update" process image are automatically updated in
each program cycle. See also the Process images and process image partitions (Page 89)
section.
Execution of the user program
Once the CPU has read the inputs, the cyclic program is executed from the first instruction to
the last instruction.
If you have configured a minimum cycle time, the CPU will not end the cycle until this
minimum cycle time is up even if the user program is completed sooner.
A maximum cycle time is set which you can adjust according to your requirements. This
ensures that the cyclic program is completed within a specified time. If the cyclic program
has not finished running within this time, the system responds with a time error.
Further events such as hardware interrupts and diagnostic interrupts can interrupt the cyclic
program flow and prolong the cycle time.
Reference
Further information about cycle and response times is available in the Function Handbook
Cycle and response times (http://support.automation.siemens.com/WW/view/en/59193558).
S7-1500 Automation System
System Manual, 01/2013, A5E03461182-01
Commissioning
8.4 Operating modes
105