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The specific mission of DTT [1] will be to explore viable solutions to the power exhaust issues in a fusion reactor in view of DEMO. The ultimate goal will be to qualify and control in various divertor configurations the heat fluxes through the plasma edge in a way that preserves both the integrity of the plasma facing components and the quality of the plasma performance. In this paper we describe the initial approach to the system of diagnostics, data acquisition and control infrastructure foreseen on DTT. The idea behind this approach is that the system of sensors, actuators, models and communication infrastructures must be conceived in an integrated way.This is mandatory in order to assure that the many interlaced functions of a complex fusion device, such as plasma control, machine-protection and safety, are fulfilled simultaneously. In the second place,whereby some redundancy is foreseen for model validation and reliable feedback control purposes it is important to bear in mind that one of the ultimate goals of DTT will be to explore DEMO relevant ways to control complex situations, that is with a minimal amount of direct measurements of the plasma parameters. This is to be accomplished by relying more and more on physics and engineering models driven controls[2].The compatibility of the diagnostics with the present machine design has been verified particularly with regard to the geometry and paying attention to several other important specifications such as electromagnetic and radiation compatibility as well as maintenance issues. However an exhaustive verification of all these aspects is beyond the scope of this work. n Chapter 2 the diagnostics system is described, mainly in terms of their functionalities and their main specifications. A set of fundamental diagnostic has been selected for both the development of the scientific basis of the experiment, the protection of the machine and the stable operation of the discharge under robust real time control. Chapter 3 describes in more details some of the principal situations where feedback control will be necessary for assuring long pulses,with particular reference to the specific mission of DTT. Data acquisition and control system that have been conceived according to modern schemes and tools are illustrated in Chapter 4 before some final remarks.

The system of diagnostics, data acquisition and control foreseen on the Divertor Test Tokamak experiment (DTT) is presented. Conceived in an integrated way, the control system meets the specifications of a fusion experiment devoted to the study of the power exhaust problem in view of DEMO. Diagnostics and feedback control are particularly functional to the need of maintaining the plasma close to equilibrium in situations prone to instabilities where the plasma wall interaction is optimized. Strongly oriented to the exploration of control methods suitable for DEMO, DTT will specifically experiment on physics and engineering model based control systems. Control and data flow schemes are inspired by those of ITER.