Global Muon Trigger Readout (preliminary, as of 30 Jan 2004)

Format on SLINK

the following table lists the format of the GMT readout data on the 64-bit SLINK from the GTFE card to DAQ. The table contains only the detector payload. Standard header and trailer words enclose this payload.

    Bit Nr
63
31
board 0: GMT B X -1 header board_id(8), 000, length_in_w64(5), bx_in_event (4), ref_bc_nr (12) bx_errors_per_chip (8), evt_nr (24)

Input Muons

from 4 Input FPGAs

 

DT Muon 1
DT Muon 0
DT Muon 3
DT Muon 2
bRPC Muon 1
bRPC Muon 0
bRPC Muon 3
bRPC Muon 2
CSC Muon 1
CSC Muon 0
CSC Muon 3
CSC Muon 2
fRPC Muon 1
fRPC Muon 0
fRPC Muon 3
fRPC Muon 2

GMT Muons and Ranks

from Sort FPGA

 

barrel GMT Muon 1
barrel GMT Muon 0
barrel GMTMuon 3
barrel GMTMuon 2
forward GMT Muon 1
forward GMT Muon 0
forward GMTMuon 3
forward GMTMuon 2
GMT Muon 1
GMT Muon 0
GMTMuon 3
GMTMuon 2
Rank fGMT 3 Rank fGMT 2 Rank fGMT 1 Rank fGMT 0 Rank bGMT 3 Rank bGMT 2 Rank bGMT 1 Rank bGMT 0
B X 0 header ... ...
Input Muons
GMT Muons
B X 1   ... ...

board 1: e.g. PSB1

B X -1   ... ...
B X 0   ... ...

16 input + 12 output muons + header + sort ranks: 64 bits x 16 x 3 bx = 1024 bits x 3 bx= 3072bits

Coding of Header Fields

board_id 8 bit unsigned: ID of board inside GT crate
length_in_w64 5 bit unsigned: length of record for this bx in w64, including the header w64 (for GMT board: 16)
bx_in_event 3 bit signed: bunch crossing in the current readout record: values 1,2,3,4,5 meaning (-2 .. 2)
ref_bc_nr 12 bit: reference bunch crossing counter inside orbit (from ROP chip)
bx_errors_per_chip 8 bit: bx error bits for up to 8 boards that are read out by one ROP chip. (1 if disagreement in bx number)
evt_number 24 bit event number (from ROP)

Coding of Muon Fields

Type / Bit Nr 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
input muons type BXERR SE B2 B1 B0 VCH CH H/F eta(6) qual(3) pt(5) phi(8)
GMT muons isRPC isFWD iRPC iDT/CSC SY/SGN MIP ISO eta(6) qual(3) pt(5) phi(8)

Fields for input muons (DT, CSC, bRPC, fRPC)

type type of input muon: DT:00, CSC:01, bRPC:10, fRPC:11
BXERR bunch crossing error: B0..B2 does not match reference bx counter
SE sync error flag from regional trigger
B2 bunch counter bit 2
B1 bunch counter bit 1
B0 bunch counter bit 0
VCH valid charge (1 if charge is valid)
CH charge: positiv:0, negative: 1
H/F halo bit for CSC ( 1 if halo), eta_is_fine bit for DT (1 if fine), not used for RPC
eta eta coordinate (specific scale)
qual quality code
pt eta coordinate (common scale) (empty muon has pt=0)
phi phi coordinate (0..143dec)

Fields for Output Muons

isRPC RPC flag: 1 if GMT muon is an RPC muon, 0 if it is a DT/CSC muon. Ignore bit if GMT muon is matched.
isFWD Forward flag: 1 if GMT muon if from fwd part, 0 if it is from brl part
iRPC index of brlRPC (if barrel) or of fwdRPC (if fwd) input muon (needed by HLT)
iDT/CSC index of DT (if barrel) or of CSC (if fwd) input muon (needed by HLT)
SY/SGN Sync / sign of charge code: pos: 00, neg: 01, unkown: 10, sync : 11
MIP Minimum Ionizing Particle bit (1 if muon is MIP)
ISO Isolation bit (1 if muon is isolated)
eta eta coordinate (preudo sign in MSB)
qual quality code
pt eta coordinate (common scale) (empty muon has pt=0)
phi phi coordinate (0..143dec)

Debug Options

Calorimeter Fields

MIP/ISO bits: 252 bits x 2 (MIP/ISO) x 3 bx = 1512 bits

Zero Suppression Options

No zero suppression is planned for GMT data.


Hannes Sakulin, 30 Jan 2004