Cycle and Reaction times
3-5
PLC S7-300, CPU Specifications CPU 312 IFM to CPU 318-2 DP
A5E00111190-01
Longest Response Time
Figure 3-3 shows the conditions that result in the longest response time.
Operating
system
User
program
PII
While the PII is being read in, the status of
the observed input changes. The change in
the input signal is no longer taken into
account in the PII.
PIO
The change in the input signal is taken
account of in the PII here.
The change in the input signal is processed
by the user program here.
The response of the user program to the
input signal change is passed on to the
outputs here.
Response Time
Delay of the inputs + bus runtime on
the PROFIBUS-DP
Delay of the outputs + bus runtime on
the PROFIBUS-DP
Operating
system
User
program
PII
PIO
Figure 3-3 Longest Response Time