mdsplus data acquisition in RFX and its integration in legacy systems

The current reconstruction of the RFX power supplies requires a re-engineering of the data acquisition system. The use of mdsplus has been retained, based however on a different architectural organisation. This has been possible as mdsplus is available under many software platforms, including windows and several flavours of unix. The RFX data acquisition architecture defines now a set of compactPCI (cPCI) crates, each hosting a CPU running embedded linux. Each CPU supervises local data acquisition, possibly performing data pre-processing to reduce the amount of data to be stored. Communication among distributed components is achieved using mdsip, the TCP/IP-based data communication layer of mdsplus. This distributed approach allows also the integration of legacy CAMAC-based data acquisition systems and new diagnostic systems using windows PCs for data acquisition. The same approach has been taken for integrating mdsplus subsystems in other experiments, such as spectroscopic and Thomson Scattering diagnostics currently used at FTU and TCV, respectively.