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Acces s ing data v ia PRO F I BUS
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Operating manual for PROFIBUS fieldbus | DOC01185928-0008 | 2016-12 | V1.8 EN
4.3.3
Indirect access
The slot "0" and index "0" and "1" are used for indirect access.
The reading and writing of the non-cyclical data is carried out here in 2 steps.
The following depiction should be helpful to you in implementing the two steps.
In the first step, a value 0 - 511
*
must be written into the address directory of the INVEOR by the
PROFIBUS master via slot "0", index "0".
In the example presented above, the value "320" was written into the address directory.
In the second step, the PROFIBUS master (reading/writing) accesses through slot "0", index "1",
the value addressed by the address directory.
IMPORTANT INFORMATION
Prior to accessing slot "0" and index "1", the correct description of the address directory is
absolutely necessary.
The transfer will otherwise be cancelled with an error message.
In the example presented above, the PROFIBUS master reads and writes the value "10000" into
the parameter "320" of the parameter table.
*
Maximum number of parameters for INVEOR