Conditional Cycle Mode; Cycle Time For The Conditional Cycle Of Sm 335 - Siemens SIMATIC S7-300 Manual

Properties and technical data of SM 335
1.6 Operating modes of SM 335
1.6.2

Conditional cycle mode

Conditional cycle
You can setup a fixed cycle time in the conditional cycle mode. After all analog inputs have
been converted, SM 335 outputs an optional end of cycle interrupt to the CPU; refer to
chapter Hardware interrupt (Page 60). SM 335 now goes into wait state until the analog
outputs were updated and starts the next processing cycle on expiration of the specified
cycle time.
The end of cycle interrupt can be used to synchronize a user program by calling OB 40. This
interrupt also facilitates fast execution of the user program (e.g., for control loop routines).
To activate the conditional cycle, set up a cycle time of 1 to 16 ms for SM 335 in HW Config.
The following figure shows the structure of the cycle time for the conditional cycle.
Figure 1-4
24

Cycle time for the conditional cycle of SM 335

SM 335 - High-speed analog mixed module for SIMATIC S7-300
Manual, 02/2009, A5E02409063-01