The Road Warrior: first use of the Pulsar for SVT The problem: 5/5 + XFT To raise efficiency SVT can run in 4/5 mode + XFT. But … the tracks with all the 5/5 hits come outs from the AM 6 times (about 70 % of roads are ghosts) The TF receives each track and process it -> replicate tracks are processed 6 times -> this takes to much time to make 4/5 mode usable One possible solution is to flag each replicated track, so that the TF can skip it. The Road Warrior firmware, implemented in the Pulsar , performs this function

How it is done ? We implement a pseudo-CAM (or a simple AM) : ROAD-PACKET: I LAYER II LAYER III LAYER IV LAYER OUT TO TF V LAYER STORE EACH HIT IN A TMP REGISTER, IN THE RIGHT POSITION XFT ROAD PHI 1 I LAYER II LAYER III LAYER IV LAYER V LAYER XFT I LAYER II LAYER III LAYER IV LAYER V LAYER XFT I LAYER II LAYER III LAYER IV LAYER V LAYER XFT I LAYER II LAYER III LAYER IV LAYER V LAYER XFT I LAYER II LAYER III LAYER IV LAYER V LAYER XFT IF MATCH = 1 : PHI = 0xF ELSE STORE TMP_WORD TO NEXT AVAILABLE AM PATTERN MATCH IF : AT LEAST 4/5 HITS + XFT

The logic is implemented in the Pulsar control FPGA The CAM is 64 words x 108 bits (64 is the maximum number roads/event) It is organized as a 3-stage pipeline The clock runs at 30 Mhz Works without adding any delay, except 3 clocks latency Implements a VME interface, copied from Muon pulsar firmware (thx Sakari) Through VME it is possible to choose a pass-through mode or rw mode 70 % of the control FPGA is used

STATUS/PLANS: The firmware was tested at the SVT teststand in November We have now a pulsar in Pisa and we have replicated what we did at FNAL The nearest plan is to make further tests in Pisa up to the end of march We want to make some beam tests just after the shutdown To test in the real SVT no additional work is necessary: just to enable the road warrior mode and to use the TF with the current firmware, which simply transmits the phi sector without looking at it, then to look at SVTD offline (the right AMS uCODE has to be loaded) The final commissioning requires a slight modification to the TF firmware (already done ? ) We also want to add spy buffers to the firmware, but this is not necessary for the baseline