In order to make data from IO-Link devices usable in higher-level systems, the IO-Link protocol and data model must be converted accordingly. The IO-Link masters are responsible for the protocol implementation. The IODD describes the data model of the IO-Link devices and is used for integration at the application level.

The importance of standardized vertical integration becomes clear using the example of profiles such as the Common Profile or Smart Sensor Profile. There are so-called proxy function blocks for this profile, which make the profile functions available to the application programmer regardless of the IO-Link master and device manufacturer used.

However, this only works if the transport and implementation of the data are specified right up to the application interface. This includes, for example:

  • Measured values ​​and setpoints
  • Device parameters
  • Diagnostics and error messages
  • Configuration of the IO-Link Master

For these specifications, the IO-Link community works together with the user organizations for the respective systems. So far, there are specifications for the integration of:

The implementation is most consistently implemented in PROFINET. In addition to the specification for IO-Link, there is also the specification for safety-related communication with PROFIsafe and IO-Link Safety. In addition, work is being done to integrate the mapping into the PROFINET test system and make it certifiable.

In addition to integration into the fieldbus systems and thus into the control systems (mostly PLC), integration into the IT world, such as ERP systems or the connection to visualization and operating systems, is also important. The IO-Link community has contributed itself here and, in collaboration with the OPC Foundation, has created the document “OPC Unified Architecture for IO-Link Companion Specification”.

With the specification “JSON Integration for IO-Link”, the IO-Link community has created a simple way to integrate with IT solutions or cloud solutions. JSON (JavaScript Object Notation) is a very simple data format that can be transmitted via a REST API or via MQTT (Message Queuing Telemetry Transport). JSON is very lightweight and uses significantly less resources than OPC UA. This means that data from and to the IT level can be transmitted and used seamlessly and in an easily interpretable manner.