Instruction Manual PSx3xxPN
10
2.7
PROFINET interface
When setting up the project, care should be taken to use the appropriate DAP (either
“PSx with 1 connector” or “PSx with 2 connectors”). When choosing the wrong DAP,
no communication will establish.
Although the mode
“IRT” is mentioned in the GSD file associated to the
device, currently only the mode
“RT” is supported.
Process data:
As process data for the IO controller a 14-byte output module and a 16-byte input
module exist. With the help of the process data, the positioning commands are
initiated and monitored, besides parameters might be written and read. For that
purpose, the “PKW parameter interface” is being used, which is described in the drive
profile “Profidrive”.
Acyclic read and write requests:
Access on all parameters is also possible with acyclic read and write requests instead
via the PKW parameter interface. The parameter number is in both cases the same.
When using acyclic write requests, it has to be considered that just before the
effective value which a parameter shall receive, a control byte has to be transmitted,
which specifys if the drive shall execute or ignore the write request. If the write
request shall be ignored, this control byte has to be set to 0, otherwise the write
request will be executed.
Thus, the data length of the write requests result to 3 byte for 16-bit values
and 5 byte for 32-bit values.
For acyclic reading, the data length of the returned value is 2 byte for 16-bit
values and 4 byte for 32-bit values.
The advantage of this method is when doing a parametrization in the context of
running up a device, a parameter might be taken over out of the project design or
alternatively the values which are stored in the EEPROM of the drive keep their
validity. This is being controlled by the control byte which was described before and
which is present for each parameter in the GSD file and which is being displayed in
the project design.
