1. Production Test Rig for the ATLAS Level-1 Calorimeter Trigger Digital Processors
J.R.A Booth, D.G. Charlton, C.J. Curtis, P.J.W. Faulkner, S. Hillier, G. Mahout, R.J. Staley, J.P. Thomas, D. Typaldos, P.M. Watkins, A. Watson, E.-E. Woehrling
School of Physics and Astronomy, University of  Birmingham,
Birmingham, UK
R. Achenbach, V. Andrei, F. Föhlisch, C. Geweniger, P. Hanke, E-E. Kluge, K. Mahboubi, K. Meier, F. Rühr, K. Schmitt, H.-C. Schultz-Coulon, P. Weber
Kirchhoff-Institut für Physik, University of Heidelberg,
Heidelberg, Germany
B. Bauss, S. Rieke, R. Stamen, U. Schäfer, S. Tapprogge, T. Trefzger
Institut fur Physik, Universität Mainz, Mainz, Germany
E. Eisenhandler, M. Landon
Physics Department, Queen Mary, University of London,
London, UK
B.M. Barnett, I.P. Brawn, A.O. Davis,J. Edwards, C. N. P. Gee, A.R. Gillman, V.J.O. Perera, W. Qian, D.P.C. Sankey
Rutherford Appleton Laboratory, Chilton, Oxon. UK
C. Bohm, S. Hellman, A. Hidvégi S. Silverstein
Fysikum, Stockholm University,
SE Stockholm, Sweden
Gilles MAHOUT

2. ATLAS Level-1 Calorimeter Trigger System
Calorimeters
Muon
Tracking Calo Muon
Calorimeter Trigger
Muon Trigger
75 kHz L1
e/g
tau
jet Et SE m
Fifo
Readout Driver
ROD
ROD
ROD R O B R O B R O B
1000 Hz
Readout Buffer
Central Trigger Processor L2
Event Builder
200 Hz
Front End Buffer
Region of Interest (RoIs)
Storage
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3. Identifying Clusters: e/g, tau and jets
The trigger works on a reduced granularity with trigger towers covering 0.1 x 0.1 in  x 
The e.m. and tau are based on windows of 4 x 4 trigger towers, in both e.m. and hadronic calorimeters
The jet trigger is based on windows of 4 x 4 “jet elements”, each 0.2 x 0.2 in  x  , with e.m and hadronic calorimeters summed
This windows slide in eta and phi to fully cover the calorimeter
RoIs are defined by their (h,f) coordinates – a window is a local candidate trigger object if it is a local maximum
RoIs are tested against sets of threshold values, each made up of cluster and, (for e.m. and tau) isolation energies.
Because the algorithms involve overlapping data, Trigger Tower data are shared:
between algorithm chips onboard
between modules, across a custom-built backplane
Module 0
Module 1
Module 2
Module 3
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4. Central Trigger Processor
System Data flow
~7200 Calorimeter
Trigger Towers
Jet/Energy Processor
Pre-Processor
141 GBytes/s
589 GBytes/s
0.7 GBytes/s
Central Trigger Processor
Cluster Processor
448 GBytes/s
75 kHz
L1A
Data Check
RoI
Level 2
Readout
Gilles MAHOUT

5. ATLAS Level-1 Calorimeter Trigger System
Input/output data
DAQ
RODs
To DAQ
Jet / ET
(JEP)
2 ROD crates
RoI
RODs
0.2 x 0.2
To CTP
To L2
Pre-
Processor
(PPr)
2 JEP crates
Feature
types/
positions
e/, /had
Clusters
(CP)
Analogue
tower sums 0.1 x 0.1
(~7200)
(>300 Gbyte/s)
To CTP
8 PPr crates
0.1 x 0.1
4 CP crates
Fibre
F/O
Slow
Control
CANbus
TTC
CTP
DCS
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6. Level-1 Calorimeter Trigger System: Production Test Rig
All digital boards have passed their Production Readiness Review pending a full crate test made on pre-production modules: Cluster Processor Modules and Jet/Energy Modules.
Need to gear up to the equivalent of ¼ of full trigger in one crate
Additional production boards were manufactured
Need to emulate calorimeter LVDS: special boards have been built to source data
Ordered LVDS cables with final ATLAS length
link cables needed for final system, around 300 per crate
Production custom-built backplane available for the test
Additional tests
Generate 18 active links to fully populate the ROD input
Test of the DCS with a full crate of boards:
Monitoring on-board currents, voltages and temperatures using PVSS
Simulation of the hardware easily expandable to accommodate several crates and modules
Gilles MAHOUT

7. Calorimeter signals: LVDS Source Modules
Custom built LVDS Source Modules (LSM) have been used as source of 400 Mbit/s serial LVDS
1 LSM per board
Custom backplane receives the emulated calorimeter LVDS from the rear
Final number
308 cables
14 LSMs
28 TTCrx chips on mezzanine board
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8. Cluster Processor Module: Full Crate Test
Contents of the crate
14 CPMs
1 CPU mounted on a special adaptor card to fit the custom backplane
1 board designed to broadcast the TTC clock to each individual module via the backplane; also provide interface to external CANbus
2 Common Merger Modules
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9. Cluster Processor Module: Crate Test results
Patterns used
Ramp to test LVDS input
Test vector with programmable occupancy rate
Long term measurement
No parity error observed in 5 hours on real time data directly seen from the source, or through backplane
Timing window investigation
For the fastest links, data across backplane show parity error free window of 2 ns
Crate Power Consumption
~ 200 A at 10% occupancy (<300 A, in PSU specification)
P ~ 1 kW
FPGA behaviour
Big FPGA temperature less than 45oC
Internal current within specification
Chip #
(.1 ns)
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10. Jet/Energy Module: Crate Test Results
Contents of the crate as before, but with 7 JEMs instead of CPMs
Empty slot between board types to avoid data mismatched across backplane
Results:
No links lost on LVDS
No parity errors observed after 5 hours across the backplane
10-bits Ramp
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11. Common Merger Module 10 ns Two CMMs in crate
No parity errors in 5 hours on backplane data
All CMM inputs show wide parity error free windows with CPMs as inputs
No boards
10 ns
Parity Errors
No Parity Errors
(.1ns)
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12. ROD Test ROD can receive up to 18 modules via G-links Results:
16 boards connected
Results:
No parity errors observed in 1 hour
5 CPMs feeding ROD had no data errors after 200k events
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13. Detector Control System on crate
CANbus using CANOpen protocol to read out all temperatures and currents of up to 14 modules
PVSS used to monitor currents, voltages and temperatures
Alarm implemented and successfully tested
Overnight runs possible during production phase
Gilles MAHOUT

14. Conclusions The full-crate tests have been successful:
Debug early problems in comfort of the laboratory rather than in the ATLAS pit
Check stability of the digital board designs
Check crate power consumption
Scale up DCS to several boards and crates
All boards are into production now
First production modules are now being used in ATLAS pit
Gilles MAHOUT