IEEE International Workshop on Intelligent Data Acquisition and Advanced Computing Systems: Technology and Applications 21-23 September 2009, Rende (Cosenza), Italy 978-1-4244-4881-4/09/$25.00 ©2009 IEEE 107 The FF-LYNX Project: Design of Fast and Flexible Protocols and HW Interfaces for Data Acquisition and TTC Distribution in High Energy Physics Experiments S.Saponara 2 , G.Bianchi 1,2 , R.Castaldi 1 , L.Fanucci 2 , G. Magazzù 1 , C.Tongiani 1,2 , P.G.Verdini 1 1 INFN – Sezione di Pisa, Largo B. Pontecorvo, 3. I-56127. Pisa (Italy), http://www.pi.infn.it 2 Università di Pisa, Dipartimento di Ingegneria dell’Informazione, Via G. Caruso 16, I-56122 Pisa (Italy), http://dip-iet.iet.unipi.it Abstract – The FF-LYNX project, aimed at the design of an innovative data transmission protocol for High Energy Physics experiments and its implementation in rad-hard, low-power interfaces, is described in this document. An outline of the present project status and results is presented, as well as the foreseen future activity. Keywords - High Energy Physics experiments, Data Acquisition, timing distribution, trigger, transmission protocol and interfaces I. INTRODUCTION Current High Energy Physics (HEP) experiments (e.g.: the ATLAS and the CMS experiments at the CERN Large Hadron Collider) have systems for the distribution of the Timing, Trigger and Control signals (TTC) and for the Data Acquisition (DAQ) with very similar architectures (Fig. 1). Signals generated by the interaction with sensors (e.g.: charges generated in silicon sensors) of particles produced in the beam collisions are handled by conditioning electronics (Front-End electronics) embedded in the detectors (e.g.: charge amplifiers, shapers, sample and hold circuits, buffer analog or digital memories, Analog to Digital Converters) and optically transferred to remote DAQ systems far away from the experiment’s area. The DAQ systems constantly receive a stream of data from a subset of the sensors which is used to detect significant events: if such an event is detected the DAQ system sends a trigger to the Front-End electronics which commands the start of a full-scale DAQ process from all the detectors. A remote control system manages the configuration and monitoring processes in the Front- End electronics. The Large Hadron Collider (LHC) will start data taking in 2009, but physicists and engineers are already focused on the R&D activities related to the two-phase upgrade of LHC scheduled for 2013 and 2018 [3,4,6]. Most of the detectors will be redesigned and new sensor technologies will be used, but the experiments will still share most of the requirements with respect to data-rate, trigger latency, robustness against transmission errors and component failures, radiation hardness and power dissipation of hardware components. A key lesson from the past ten Fig. 1. General architecture of a the control and readout system of a HEP experiment. years of activity in the design, production and integration of the large experiments for the LHC is that the use of common solutions for different detectors and experiments reduces efforts and resources and minimizes risks. Electrical serial links between Integrated Circuits (IC) implementing the Front-End electronics and the radiation tolerant Electrical to Optical Converters (EOCs) with bandwidth of the order of several Gbps will be required. The electrical serial links will have to cover a wide range of data-rates from tenths of Mbps from each IC through intermediate stages of data concentration (e.g. in the outer layers of the Silicon Strip Trackers at about 1m from the interaction point) to one Gbps (in the inner layer of the Silicon pixel detector at few cm from the interaction point) with direct high speed connections between Front- End ICs and EOCs. Standard protocols used in telecommunications, consumer electronics and automotive industry are not suitable for this field of application, failing to satisfy the stringent requirements above mentioned especially about radiation hardness and fault tolerance [7-9]. In this perspective the activity and the aims of the FF-LYNX project, funded by the INFN (Italian National Institute for Nuclear Physics) 5th Commission, appear to