1. ATLAS: Level-1 Calorimeter Trigger
Level-1 triggering in ATLAS
Developments since last report in 1999
Hardware status
Software status
Plans and Milestones
Institutes: Birmingham, Heidelberg, Mainz, QMUL, RAL, Stockholm
UK makes up ˜50% of staff and finance
UK provides most of the leadership:
Overall Coordinator – Eric Eisenhandler
Hardware Coordinator – Tony Gillman
Software Coordinator – Murrough Landon
September 30th, 2002
PPRP - ATLAS Level-1 Calorimeter Trigger Status

2. Level-1 triggering in ATLAS
LHC Proton-proton interaction rate is approximately 1 GHz
Data stored at bunch-crossing rate of 40 MHz for 2 ms
Three-stage triggering system
Level-1: custom built hardware, fixed latency – target rate 75 kHz
Level-2: software, RoI based selection – target rate 1000 Hz
Event Filter: software, full detector – target rate 100 Hz
Level-1 has three sub-systems:
Calorimeter Trigger
Muon Trigger
Central Trigger (CTP)
September 30th, 2002
PPRP - ATLAS Level-1 Calorimeter Trigger Status

3. Level-1 Calorimeter Trigger Architecture
September 30th, 2002
PPRP - ATLAS Level-1 Calorimeter Trigger Status

4. Position at last report
Plus some bright ideas and backup R&D:
Use LVDS to provide low power consumption link technology
Exploit rapidly improving FPGA technology
Increase use of common modules, backplanes
Led to an improved architecture specification
Majority of Glinks gone
No need for ASICs or Multi-Chip Modules in UK processor
FPGA use increases flexibility
September 30th, 2002
PPRP - ATLAS Level-1 Calorimeter Trigger Status

5. Improved system architecture
Common results merger module (CMM) hardware design with different firmware handles:
Electromagnetic and tau objects
Jet objects
Energy objects (missing ET etc)
Common Timing Control Module
Common custom backplane for em and jet system
Some new algorithms
NB: also additional flexibility (from FPGAs)
Responsibilities were rearranged
With no loss of importance of UK
September 30th, 2002
PPRP - ATLAS Level-1 Calorimeter Trigger Status

6. Project progress: Hardware Status
Testing prototypes of all UK modules
All but one module are full ATLAS specification
Most complex is the Cluster Processor Module (CPM)
32 FPGAs (8 Xilinx XCV1000E)
80 LVDS de-serialisers
Approximately 80 G bits/sec i/o through rear connector (needed for algorithm fan-out)
56 needed in full system
First module under test
Boundary scan very useful
Firmware tested in several ways
Hardware so far a success
September 30th, 2002
PPRP - ATLAS Level-1 Calorimeter Trigger Status

7. PPRP - ATLAS Level-1 Calorimeter Trigger Status
Other UK modules
Common Merger Module under test…
With first of three required firmware versions
Readout Driver (ROD) under test for more than one year
Also carried out integration tests with RoIB at CERN
Several Timing Control Modules exist and are already in use
Further standalone test modules also in use
September 30th, 2002
PPRP - ATLAS Level-1 Calorimeter Trigger Status

8. Status of Hardware outside the UK
Stockholm: Four custom backplanes built, two already in use (1150 pins per slot)
Some connectivity tested
Mainz: Nearly full specification Jet/Energy Module in existence for some time
Heidelberg: Pre-processor Module still to be built, but crucial Multi-Chip Module under test. Contains:
4 FADCs
1 ASIC (now only ASIC in system)
3 LVDS serialisers
70mm
September 30th, 2002
PPRP - ATLAS Level-1 Calorimeter Trigger Status

9. Firmware, online and offline software
Firmware – closer to software or hardware?
FPGAs have improved flexibility, functionality
New algorithms
‘One size fits all’
However, require extended development time
Many different firmware loads necessary
Firmware development cycle more similar to software
New tools and skills required for testing/debugging
Request for more TD effort
Time profile extended
Online Software
Ambitious programme - prototype of ‘final’ software
Diagnostic package – HDMC
Detailed problem analysis
Calibration
Integration with standard ATLAS Online packages and ROS
Software currently lags behind hardware
Shortage of effort
Offline Software
New ATHENA based simulation is almost complete
September 30th, 2002
PPRP - ATLAS Level-1 Calorimeter Trigger Status

10. PPRP - ATLAS Level-1 Calorimeter Trigger Status
Plans and Milestones
All modules currently in stand-alone test programme
Next step - integrate modules to test communication (subsystem tests)
When subsystems understood, proceed to Slice Test
Complete cross-section through trigger system (including CTPD)
Vital programme of system-wide integration and testing
Start subsystem tests (Oct2002)
Start slice tests (Mar 2003)
Finish slice tests (Dec 2003)
Final reviews (early 2004)
Module production (mid 2004)
Full system tests (Oct 2004)
Finish test programme (Oct 2005)
Trigger available in situ (Aug 2006)
Future Milestone Highlights:
September 30th, 2002
PPRP - ATLAS Level-1 Calorimeter Trigger Status

11. Plan for 2003 Slice Test with full specification modules
All coloured modules are UK responsibility
September 30th, 2002
PPRP - ATLAS Level-1 Calorimeter Trigger Status

12. PPRP - ATLAS Level-1 Calorimeter Trigger Status
Conclusions
Much progress since last report
Currently testing full specification modules
Shown that necessary module complexity and connectivity is feasible
Ambitious test programme beginning
On completion, final module production can start
Schedule slippage problems
Mostly due to firmware/software effort shortage
With sufficient resources we are confident of project completion on schedule
September 30th, 2002
PPRP - ATLAS Level-1 Calorimeter Trigger Status