RPC Electronics Technical Trigger Outline RPC-based Technical

RPC Electronics: Technical Trigger Outline: • RPC-based Technical Trigger • Principles of operation • Implementation • MTCC readiness Flavio Loddo I. N. F. N. Bari On behalf of the RPC-Trigger group Annual Review Cern -June 13 th, 2006 F. Loddo I. N. F. N. Bari

RPC Technical Trigger Goal of this project is to produce an RPC-based cosmic ray trigger for the Commissioning of RPCs, the Cosmic Challenge and later running of CMS as Technical Trigger The project started recently, when electronics and cabling in the cavern were defined and frozen ↓ Use existing infrastructure (as much as possible) and don’t introduce major modifications to the existing electronics (Link Boards) Annual Review Cern -June 13 th, 2006 F. Loddo I. N. F. N. Bari

Block Diagram of RPC Electronics full chain Annual Review Cern -June 13 th, 2006 F. Loddo I. N. F. N. Bari

RPC Technical Trigger Phase I: Sector Trigger for testing RPC (and DT) during Commissioning and MTCC RPC Cosmic trigger RBC (RPC Balcony Collector) Phase II: Technical trigger to be used during offbeam periods for detector calibration RBC + TTU (Technical Trigger Unit) Annual Review Cern -June 13 th, 2006 F. Loddo I. N. F. N. Bari

RPC Technical Trigger UXC area LBBox 1 RBC/ 2 sectors USC area LBBox RBC LBBox Technical Trigger Unit Readout Crate LBBox Fiber TTU Barrel Wheel Receiving panel RBC TTU RBC LBBox RBC LBBox RBC (RPC Balcony Collector) TTU LBBox TTU 6 Fibers/wheel Annual Review Cern -June 13 th, 2006 30 Optical Fibers F. Loddo I. N. F. N. Bari

RBC Implementation • The RPC signal cables (LVDS) are connected to the Link Boards (LB) for synchronization, data compression and optical conversion • Each LB reads 96 strips (1 bi-gap = half/chamber) and can produce 1 OR to be used for our goal • Each LBBox (LBB) houses 13 or 15 (sect. 4 and 10) LBs of 1 Barrel Sector • The LBBs are distributed in the 30 periphery racks in groups of 2: one odd sector and one even sector We can house 1 RBC/rack 1 RBC/2 sect 30 RBCs in total Annual Review Cern -June 13 th, 2006 F. Loddo I. N. F. N. Bari

RPC LBBox • LBB's slots 11, 12, 13 are always free in barrel • CSC connector is not used in barrel • at least one I 2 C output is not used on backplane RBC will be located on slot 12 of LBB of all odd sectors RBC_fake will be located on slot 12 of LBB of all even sectors Annual Review Cern -June 13 th, 2006 F. Loddo I. N. F. N. Bari

Annual Review Cern -June 13 th, 2006 F. Loddo I. N. F. N. Bari

RBC Main Features • Receive 2 x 13 (or 15) ORs from LB (LVDS) Generic Barrel Sector (OR of 96 strips (1 bi-gap = half RPC)) RB 4 • Mask noisy/dead Ors • Produce Sector Trigger (LVDS), with selectable Majority level RB 3 • Force selected ORs to be in the coincidence, to RB 2_OUT increase trigger selectivity • Introduce latency for synchronization RB 2_IN • I 2 C Interface RB 1_OUT • Transmit input OR optically to Counting Room (GOL) Annual Review Cern -June 13 th, 2006 RB 1_IN F. Loddo I. N. F. N. Bari

RBC PCB Layout Optical transceiver • 10 Layers PCB 14 x 14 cm 2 GOL (small board to save money) • to be housed on Mother Board, fitting LBBox dimensions Z-Pack Conn. JTAG Conn. FPGA Annual Review Cern -June 13 th, 2006 F. Loddo I. N. F. N. Bari

RBC Motherboard Layout Front side Backplane connector: • 3. 3 V • 2. 5 V • GND • I 2 C Low profile connector (5 mm) to connect RBC to Motheboard Annual Review Cern -June 13 th, 2006 F. Loddo I. N. F. N. Bari

Quantities • 30 RBC (10 layers PCBs 14 x 14 cm 2) • 30 RBC Mother Boards (2 layers PCBs 16 x 46 cm 2) • 30 RBC_FAKE (4 layers PCBs 2 x 4 cm 2) • 60 RBC_FP 1 (4 layers PCBs 18 x 14 cm 2) • 60 RBC_FP 2 (4 layers PCBs 18 x 14 cm 2) Annual Review Cern -June 13 th, 2006 F. Loddo I. N. F. N. Bari

RPC Technical Trigger for MTCC Two RBC (RPC Balcony Collector) can be used during the MTCC to provide two Cosmic Triggers to the LTC (or PSB), based on the coincidence of half chamber ORs coming from the LBs W+2: Sect. 10 Sect. 11 Sect. 10 -11 patterns W+1: Sect. 10 Annual Review OR Trig_+2 Trig_+1 Cern -June 13 th, 2006 F. Loddo I. N. F. N. Bari

RBC testing for MTCC • Because of long distance (150 m) between Detector and “Green Barrack” during MTCC, we could send the Technical Trigger in LVPECL, that is more robust than LVDS and introduce optocouplers to cut ground loops RBC LVDSLVPECL Transceiv. 150 m (shielded twisted cable) LVPECL Receiv. LVDS Driver LTC Or PSB • This configuration was succesfully tested in Bld. 904 with both LTC and PSB • Preliminary latency estimate: 45 bx Annual Review Cern -June 13 th, 2006 F. Loddo I. N. F. N. Bari

RPC Technical Trigger Implementation USC area LBBox RBC LBBox Fiber LBBox Technical Trigger Unit TTU Barrel Wheel Receiving panel RBC TTU RBC LBBox RBC LBBox RBC (RPC Balcony Collector) TTU LBBox TTU 6 Fibers/wheel Annual Review Cern -June 13 th, 2006 30 Optical Fibers F. Loddo I. N. F. N. Bari To Global Trigger UXC area

TTU (Technical Trigger Unit) Block Diagram ( • Receive optical link from RBCs • Combine ORs from 1 Wheel and produce Wheel Cosmic Trigger • To be housed in the counting room 6 x 16 bit data TLK 2501 TLK 2501 HFBR-5720 6 x 16 bit data 6 Fibers Programmable Majority Unit or Pattern Recognition Processor Deskewed HF clock VME Interface Comm. line Annual Review QPLL TTCrx LHC Clock Cern -June 13 th, 2006 F. Loddo I. N. F. N. Bari Wheel Trigger

RPC Trigger Board as TTU These functions are performed by the RPC Trigger Board: • TTU needs: 1. 30 signals from detector: 1. 6 GHz GOL drive multimode fiber; 2. each fiber transfers 26 or 28 bits @ 40 MHz; 3. Signals must be synchronized; 4. Pattern logic to make cosmic trigger • RPC Trigger Board offers: 1. 18 inputs: 1. 6 GHz GOL driven multimode fiber; 2. Opto synch FPGA for every 3 optical inputs; 3. Transmission to PAC mezzanine boards (VHDL code) 4. VHDL code for Internal Interace (for VME driven internal bus and software tools) Annual Review Cern -June 13 th, 2006 F. Loddo I. N. F. N. Bari

RPC Trigger Board as TTU 1. 3 TBs can be used to cover the whole Barrel, using 12 links per TB 2. The Stratix 2 PAC mezzanine board gives very big space for algorithm (1 or 2 should be enough) 3. TTU custom backplane (for TTCrx and to send out the Trigger) but be designed, but can be derived from the design of TB backplane Annual Review Cern -June 13 th, 2006 F. Loddo I. N. F. N. Bari

Conclusions The RPC Technical Trigger project is under progress: • 3 RPC Balcony Collector (RBC) prototypes are available for MTCC • The full production is expected to be available before the end of 2006 • The design of the new firmware for the Trigger Board-TTU will start in few weeks Annual Review Cern -June 13 th, 2006 F. Loddo I. N. F. N. Bari