Physics%20trigger

1
BST info in LHCb
Physics trigger
Local trigger (Optional)
Orbit
Orbit
L0 / L1
Clock
L0 / L1
Orbit
L0 / L1
Clock
Clock
RS
RS
RS
RS
RS
TFC Switch
Throttle OR/Switch
. . .
VELO FE
ST FE
OT FE
RICH FE
ECAL FE
Event building network
2
Readout Supervisor ODIN
Data flow in Readout Supervisor
DETECTOR_STATUS
Q_L0
FE_BUFFER
L0_TRG
L0_DATA
FIFO
BUNCH_CURRENT
L0_TRIGGER
FPGA
Q_FE
DI (EGRESS)
GbE
L1_DATA
Q_L1
AFIFO
L0_DATA
L0_DATA
MEZZANINE
FPGA
DI (INGRESS)
GbE
FIFO
L1_TRG
L1_TRG
GPS
Q_MP
FPGA
TTCrs
TTCrx
TTC_DATA
LHC_TTC
L1BROADCAST COMMANDS
TTC
FPGA
MEZZANINE
MEZZANINE
3
Readout Supervisor FE

• 40 MHz. Data stored in FIFO (FPGA internal RAM)
• Bunch current 8 bits (BUNCH_CURRENT)
• Total 8 bits
• L0 Decision (1 MHz). Data stored in L1FE Buffer
  (external RAM)
• L0 bunch current 8 bits (L0_BUNCH_CURRENT
  )
• Bunch ID (RS) 12 bits (BID)
• GPS 40 bits (GPS_TIME)
• Detector status 24 bits (DET_STATUS)
• L0 Event ID 32 bits (EID)
• Trigger type 3 bits (QUAL)
• L0 Force bit 1 bit (L0_FRC_OUT)
• Bunch ID (L0DU) 12 bits (L0_BID_OUT)
• BX type 2 bits (BX_TYPE)
• L0 synch error 1 bit (L0SNC_ERR)
• L0 synch error forced 1 bit (L0SNC_KEEP)
• Total 136 bits
• L1 Decision (40 kHz). Data stored in MEP buffer
  (FPGA internal RAM)

4
LHCb BST info

• GPS
• Updated every orbit and transmitted as 8 long
  broadcasts (64 bits UTC)
• e.g. 40 bits? ms resolution 4 bits year, 9 bits
  days of the year, 17 bits seconds of the day and
  10 bits milliseconds. A 100 ms resolution could
  be obtained by dropping the year.
• Bunch clock provides additional precision
• Calibration of the UTC time locally can be
  obtained by using the LHC revolution signal
  provided we know all the timing of the
  transmitter equipment
• Machine mode
• Bunch scheme?