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Description
PROFIBUS interface
3.3
Cyclic mode
The SSM6000 DP slave features a modular design. The data modules can be combined in any order for cyclic operation. It is not
necessary to insert blank modules, and it is possible to select several modules at the same time. The only restriction is that the
maximum number of inputs and outputs (as specified in the GSD file) may not be exceeded.
The data modules selected for cyclic operation are communicated to the SSM6000 during initialization via the parameter telegram.
These additional parameters are manufacturer-specific.
3.4
Acyclic mode
The SSM6000 also enables acyclic data exchange and/or access. Acyclic reading of all input data is generally possible.
Write access to output data is only possible as long as the module to be written has not yet started the cyclic exchange of data with
the master.
If the master starts an acyclic write attempt to a data module parameterized as cyclic, the following error message is generated:
"DPV1_ERRCL_ACC_INV_SLOT" ( error code: 0B2
3.4.1
Read access
Two possibilities exist for acyclic read access to SSM6000 DP slave; these can be selected via the "index'":
DS_Read telegram:
0x5E
The module to be read is selected via the slot number.
Index 2:
The modules selected for cyclic operation correspond to the readable slots for acyclic operation. Modules not selected for cyclic
operation cannot be read in acyclic mode either.
Index 3:
The data modules can be read in the order of their basic configuration. All existing modules can be read as a corresponding slot,
irrespective of the configuration of cyclic operation.
3.4.2
Write access
The data modules ( the only module that can currently be written is the "Measurement" module) correspond to one slot each in the
order of their basic configuration.
The current version permits writing of slot 9 only and corresponds to the "Measurement" module. In the case of an attempt to write
other slot numbers, the master receives the "DPV1_ERRCL_ACC_INV_SLOT" error message (error code: 0B2
:GA-Profibus_060105-EN-pro.doc
).
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Slot_number
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Index
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05.01.2006
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