Real-time information exchange between data acquisition and control systems at ASDEX Upgrade

Today's data acquisition systems and control at the ASDEX Upgrade fusion experiment communicate during the setup of an experimental discharge only. While control executes the discharge based on recipes and a fixed number of input and output channels, diagnostic measurements are done under a predefined schema. Considerable benefits for scenario specific discharge execution are expected to be drawn from a real-time integration of data acquisition and discharge control systems: Information from the control system can be used for the real-time adaptation of the data acquisitions configuration, such as channel selection, time resolution, signal filtering, analysis process selection and protocolling functions. Information from data acquisition processed from the full set of input channels and diagnostic-specific knowledge can be used to select and fine-tune control configurations. Access to the data acquisition systems as external information sources potentially reduces the complexity of the discharge controls peripheral hardware and preprocessing software. Information exchange among these systems on a peer-to-peer basis allows freely to communicate the results. This is preferable to a master-slave concept where strict communication protocols have to be observed. In this paper we present the current work on the integration of discharge control and data acquisition at ASDEX Upgrade and give an outlook on future developments.