Siemens SIMATIC CP 440 Manual page 113

Minimum Number of CPU Cycles
The table below describes the minimum number of CPU cycles (FB/FC calls)
required to process a minimum job (32 SEND/RECEIVE bytes for the transported
user data set per program cycle). This only applies in centralized operation.
Table 6-7 Minimum Number of CPU Cycles
RECV_440
SEND_440
RES_RECV
Before the CP 440 can process an initiated job after the CPU has changed from
STOP to RUN mode, the CP-CPU startup mechanism SEND_440 must be
completed. Any jobs initiated in the meantime do not get lost. They are transmitted
to the CP 440 once startup coordination is completed.
Before the CP 440 can receive or submit a frame in the user program after a
change in the CPU mode from STOP to RUN, the CP-CPU startup mechanism
RECV_440 must be completed.
Point-to-point connection CP 440 Installation and Parameter Assignment
A5E00057742-02
Number of CPU Cycles for Processing ...
Completion without Completion with errors
errors
2
2
2
Communication Using Function Blocks
2 3
2 3
2 3
RESET/RESTART
6-25