Specifications

14 GX Configurator-PN

Example for Starting PROFINET Communication

If the data exchange mode for an IO device is set to 'automatic' (corresponding bit in

IOD_MGT_MODE is 0), the cyclic data exchange with the device is automatically initiated, when the

PROFINET Controller is started by setting IOC_START_STOP. If the device is however set to 'manu-

al' mode, the data exchange between the PROFINET Controller and the device must be started se-

parately by setting the bit in IOD_START_STOP_DEV, which corresponds to the device. The

PROFINET Controller only evaluates a bit in IOD_START_STOP_DEV, if the equivalent bit in

IOD_CMD_HSK_Y is set.

2.1.2 Cyclic Communication Area

Process Data (Cyclic Data Exchange)

From the PROFINET perspective the cyclic communication is a continuous transfer of input and out-

put data between the IO-controller and each IO-device without further interaction by the application.

In PROFINET the cyclic communication is based on the producer/consumer model. For each IO-de-

vice, the IO-controller establishes connection with a specific refresh period (duration of the cycle).

The cyclic data exchange can be individually started or stopped for each PROFINET IO-device.

Inputs and outputs are exchanged between the PLC and the PROFINET Controller via the

INPUT_DATA and OUTPUT DATA buffers.

- I/O variables configured in GX Configurator-PN are located inside these two buffers by respecting

some alignment rules.

- As these buffers can be accessed simultaneously from the PROFINET Controller and the PLC, a