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IO-Link Master with PROFINET Interface DataLine 8 Ports IP 65 / IP 66 / IP 67
67
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9.3.6
Read and write cyclic process data
52483
While the IO-Link ports are being configured, IEC addresses are generated automatically for inputs
and outputs as well as the PQI byte. To enable access to the cyclic process data in the application, the
user must couple the IEC addresses with symbolic variables. This can be done in global lists of
variables (STEP 7: [Symbols]; TIA portal: [PLC tags]).
Take the following actions in global lists of variables of the PROFINET controller:
►
Create a symbolic name and select the data type
►
Assign an IEC address to the symbolic name
►
Save the project.
Using the symbolic name, the user can read the inputs and write the outputs from the application.
► To check the validity of the cyclic process data, evaluate the PQI byte (→
PQI (Port
Qualifier Information)
(
Even if the fieldbus connection is interrupted, the PQI byte indicates that the process data is
valid. This may have an unintended impact on the control process.
► Take suitable measures to detect an interruption of the fieldbus connection.
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Read additional digital input
52549
IO-Link ports X01...X08 have a additional digital input (pin 2). The current value is mapped to the PQI
byte (
→
PQI (Port Qualifier Information)
(