The praises of IO-Link have been already been sung often enough. The benefits of the bidirectional digital communication compared to the conventional analog and digital interfaces have now been recognized worldwide. Inexpensive wiring, diagnostic features, parameterization options, intelligent data retention, simplified e-planning and not least the vendor-neutral support of the standard are impressive features for designers, e-planners and PLC programmers. But IO-Link also has its limits. There has particularly been a shortfall with regard to the integration of IO-Link devices in Profinet systems. A GSDML file (generic station description markup language) is supplied with every Profinet device. This enables the control programmer to already plan and parameterize the device in the project offline (mostly in the TIA Portal), before the project is really integrated with the network and the connected devices. Manufacturers of IO-Link devices do not equip them with their own GSDML file, and the device description comes in the form of an IODD (IO-Link device description). The Profinet engineering software cannot therefore detect the devices directly. The user has so far been forced to enter properties such as device class or manufacturer ID manually. Parameters such as measuring ranges and output signals had to be programmed or set via additional software.

IODD interpreters
only with limited suitability

These kinds of additional software act as an interpreter of IODDs into other systems, in the same way as they are already used in various software tools. These programs enable the necessary settings to be carried out on the IO-Link device. The device is then integrated into the Profinet project. This has not been a satisfactory solution, particularly in large projects.