Siemens SIMATIC ET 200S Operating Instructions Manual page 145

Synchronization with DI and Zero Mark
In order to be able to use this function, you must have selected it from the digital input
function parameters.
Figure 3-12 Once-Only and Periodic Synchronization
If you have configured synchronization with DI and zero mark, the DI serves as the HW
enable. When the HW enable is active, the 1Count5V is loaded with the load value by the
zero mark of the encoder.
You can select between once-only and periodic synchronization.
The following conditions apply:
● The counting mode must have been started with the SW gate.
● The "Enable synchronization CTRL_SYN" control bit must be set.
Technological Functions
Operating Instructions, 06/2010, A5E00124867-07
1Count5V
3.6 Count Modes
145