The TEL62: A real-time board for the NA62 Trigger and Data AcQuisition. Data flow and firmware design

The main goal of the NA62 experiment at CERN SPS is to measure the branching ratio of the ultra-rare K+→π+νν decay, collecting about 100 events in two years of data taking to test the Standard Model of Particle Physics. Readout uniformity of sub-detectors, scalability, efficient online selection and lossless high rate readout are key issues. The TEL62 boards are the common blocks of the NA62 Trigger and Data AcQuisition (TDAQ) system. TEL62s process and store hits coming from the subdetectors in a buffer according to their timestamp, extracting only those requested by the trigger system, which merges trigger primitives also produced by TEL62s. The complete dataflow and firmware organization are described.