An ATCA Embedded Data Acquisition and Control System for the Compass tokamak

Abstract The Compass tokamak is currently being installed in Prague, Czech Republic. Its control and data acquisition system is being redesigned and built from scratch and it will be based on novel digital technologies. The proposed hardware for the controller is based on the PICMG 3.0 Advanced Telecommunications Computing Architecture ™ (ATCA) standard. The platform contains one ATCA controller with a Gigabit Ethernet interface, up to 12 ATCA Digitizer-Generator-Processor (DGP) cards and trigger and clock inputs, all on a 12U shelf. The multi-core × 86-based General Purpose Processor (GPP) controller will be connected to the DGP cards by Peripheral Component Interconnect Express ™ (PCIe) point-to-point links through the ATCA backplane. Multiple-input multiple-output (MIMO) signal processing will be shared by the DGP cards using the built-in Field Programmable Gate Arrays (FPGAs) and the controller’s × 86 general processor. Eleven Aurora ™ 2.5 Gbit/s links allow to further parallelize the execution of code among several FPGAs. In order to guarantee real-time execution of the control codes a framework based on Linux and the Real-Time Application Interface (RTAI) will be used. This will explore the features provided by the new multi-core technologies. Synchronization between the subsystems will be guaranteed by a real-time event network. The interface to the system will be provided by the FireSignal control and data acquisition system. This will allow the operators and diagnostic coordinators to configure the hardware, prepare the discharges, pre-program events of interest and follow results from the discharge. FireSignal will also orchestrate the data flow coming from the different diagnostics into the database and to registered data clients.