Bonn 2010 – wissenschaftliches Programm
HK 30.5: Vortrag
Dienstag, 16. März 2010, 17:45–18:00, HG VIII
ALICE TRD GTU Simulation Framework and Multi-Event Buffering Studies — •Dirk Hutter — Kirchhoff-Insitute for Physics, University of Heidelberg
The Transition Radiation Detector (TRD) is one of the main detectors of the
ALICE experiment at the LHC.
One part of the detector is the Global Tracking Unit (GTU). It consists of 109 dedicated
FPGA-based CompactPCI boards arranged in a three-level hierarchy.
The GTU itself serves two major tasks. One is to reconstruct tracks in less than 6 µs to contribute to the Level-1 trigger decision. Furthermore it is an essential part of the TRD readout chain. It receives raw data from the Front-End Electronics (FEE) via 1 080 fiber optical links at an aggregate net bandwidth of 2.16 TBit/s while the maximum bandwidth to the data acquisition system is two orders of magnitude smaller. To minimize detector dead time during readout due to this bandwidth reduction it is indispensable to de-randomize the data stream by buffering multiple events. As the FEE only provides single event buffers this feature is implemented in the GTU.
For development and verification of multi-event buffering a detailed HDL simulation framework of the entire GTU is needed. It has to model all board types as well as inter-board connections. The interlaced trigger layout of ALICE additionally requires complex simulation input sequences covering all imaginable cases.
The simulation framework and studies for the implementation of multi-event buffering in the GTU will be presented.