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Overview of the DP Base Interface

DP Base Programming Interface for CP 5613/CP 5614

C79000-G8976-C108-01

3.7.4 Typical Sequences in Master Operation with Hardware Events

Definition

After initializing the CP as described above, the user program can activate

hardware events and wait until they arrive with semaphores.

This means that polling for new data or diagnostic information can be omitted and it

is possible to synchronize with the start of the cycle.

This mode can replace or supplement the polling described in Section 3.7.2.

The initialization of this mode, the elements of continuous operation and the

canceling of the mode are explained below.

Initializing the Semaphores

Before you can use hardware events, semaphores must be created as follows:

Step Action Meaning

Initialize a semaphore

for hardware events

(function

DP_init_sema_object)

The DP Base DLL provides semaphores

for changes in the input data, reception

of diagnostic information, cycle start and

fast logic. The selector for a data change

is, for example,

DP_OBJECT_TYPE_INPUT_CHANGE.

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Siemens SIMATIC NET PROFIBUS Manual de servicio Pagina 53