The IODDTs are predefined by the manufacturer. They contain input/output language objects belonging to a channel of an application-specific module.
CANopen 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_CPP110 which is specific to CANopen communication.
NOTE: IODDT variables can be created in two different ways:
Each IODDT contains a group of language objects which are used to control them and check their 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 the application's request, using explicit exchange instructions.
Implicit exchanges concern the status of the modules, the communication signals, the slaves, etc.
Explicit exchanges allow module parametering and diagnostics.
