Profibus DP communication has two associated IODDTs:
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T_COM_STS_GEN which applies to communication protocols except Fipio and Ethernet,
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T_COM_PBY which is specific to Profibus DP communication.
NOTE: IODDT variables can be created in two different ways:
In each IODDT there is a set of language objects that can be used to command them and verify their correct operation.
There are two types of language object:
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implicit exchange objects, which are automatically exchanged on each cycle of the task associated with the module,
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explicit exchange objects, which are exchanged on request by the project, using explicit exchange instructions.
Implicit exchanges concern the statuses of the modules, communication signals, slaves, etc.
Explicit exchanges allow you to set the module and perform diagnostics.
