RPC PAC Trigger system installation and commissioning

How we make it working…

On-line software

ResistivePlateChambers

Link Boxes Optical Links

Synchronization

Global Runs

Testing

DB service

RPC FMRPC FMRPCT TS CellRPCT TS Cell

TC access XDAQ

TC access XDAQ

Trigger and Sorter Crates

DCC/CCS crate

…

To RCMSTop FM

To TS Central Cell

…LBox’es

SC access XDAQ

SC access XDAQ…

FEBFEBFEBFEB FEBFEB

FEBFEB

FEC

VME

FEC

CCU rings

DCC accessXDAQ

DCC accessXDAQ

LBox accessXDAQ

LBox accessXDAQ

LBox accessXDAQ

LBox accessXDAQ …

DCC

I2C rings

…

VME VME

Monitoring and test manager

JAVA

Monitoring and test manager

JAVA

Config DB

Config DB

TS SubcellTS Subcell TS SubcellTS Subcell…

TStoreTStore

Condition DB

Condition DB

TS SubcellTS Subcell

Trigger emulator

XML to DIGI

DQM, reconstructionCMSSW

Output XML file with data

from hardware

Output XML file with data

from hardware

HA XDAQ

Test pulses generators control

Diagnostic readouts control

Test data generator

input XML file with test

data

orEvent Builder

Comparing and merging of data from different diag. readouts

Comparing with the test data

XML

Test ManagerDiag. modules

configuration (delays etc.) and operation

Configuration file (XML)

Configuration file (XML)

Parsing of data from diagnostic

readouts

formation of test data vectors for

pulses generators

Config. DBConfig. DB

Analysing of

interconnections

HA XDAQ

JAVA

Result logResult log

Find such position of Synchronization window and values of the delays, that the

output signal on all Link Boards are within the same BX

In the PAC the muon identification is based on the coincidence (inside 25 ns) of hits from at least three RPC chambers. Thus, the hits timing must be corrected for the

muon time of flight and time of signal propagation in chamber – Link Board cables

BX of chamber hits

Trigger

Data to lateData to early

The distributed system for control, configuration, monitoring and testing of the RPC PAC trigger electronics. Based on XDAQ and Trigger Supervisor (TS)

frameworks (C++). Java part allows to build advanced testing procedures and assures the access to the configuration database (Hibernate tehnology) .

“Pattern tests”:• test of algorithms implementation• test of optical links connections• tests of cables connections• test of boards operationTa check, if the system is working as is should

Artificial data are send by the Tests Pulses Generators and spied by the Diagnostic Readout modules – both implemented in the firmware of the trigger FPGAs

25ns

LB1

LB2

LB3

Delay

Output signal

Muon time of flight

Propagationin cables

time

Synchronization window

RPC and FEB

CMSDuring 2007 the CMS was lowered to the underground cavern. The elements of the RPC PAC Trigger system were finally,

after almost 10 years of development, produced and installed in the CMS.

But to make from those elements a working system – that was 10 000 pieces puzzle.

RPC and CSC chambers on the

endcap disc -1

444 optical fibers transmits data

from the Link Boards to the

Trigger Boards. Correctness of

connections and transmission quality was

validated with dedicated testing

procedure.

In the picture: optical links

connected to the Trigger Crates

1232 Link Boards placed in the 96 Link Boxes on the CMS balconies

receive the signals from the chambers, synchronize them,

compress and send through the optical links to the Trigger Boards

The RPC PAC Trigger is a part of the CMS Level-1 Trigger system. Its task is to identify and measure muons.

The biggest and most difficult part of the electronic system . Will work in the

radiation and magnetic field. The Installation and commissioning of the

Link Boards it was big effort!

Synchronization achieved for the cosmic muons

Karol Buńkowski

Software framework allows to control the execution of test and analyze the results

Trigger Crates

Data Acquisition

12 Trigger Crates, each contains 5 Splitter Boards and 7 Trigger Boards (TB)

Each Trigger Board contains 3 or 4 Pattern Comparator (PAC) chips, which

performs the muon recognition algorithm:the chambers hits are compared to the

predefined patterns of muon tracks with various momenta.

RPC hits are readout from the Trigger Boards by the Readout Mezzanine Boards . Further, the data are build in the events on the Data Concentrator Cards and sent via the S-Link to the FRLs. For each trigger (Level -1 Accept) the data from up to 8 consecutive BX are readout. This allows to study for example the RPC hits synchronization.

The algorithms of data acquisition system (implemented in the FPGA devices) are most complicated algorithms in the RPC system

GRUMMGlobal RUn Mid-March GREM

Global Run End of May

GREJ Global Run End of Jun

GREA Global Run End of August

GRES Global Run End of September

GRES Global Run End of November

Muon seen by the RPC chambers

CRUZET

Cosmic Run at Zero TeslaCRAFT

Cosmic Run at Four Tesla

…And the RPC PAC Trigger system only small part of the CMS experiment!!!

MTCC