EMU CSC Trigger Modes

LCT Options

Pattern LCT

TMB triggers on valid pattern in ALCT, CLCT or Both
Normally 4-layer hit for LCT,
TMB can be programmed with a 1-2 layer minimum-bias option for debug/timing tests
CLCTs only trigger "hit" CFEBs
TMB can be programmed to trigger all CFEBs for any ALCT or CLCT "hit" on the CSC

note: Must ensure that the ALCT instance gets to the DMB/CFEB within usual CLCT time window

TMB can be programmed to request an L1A from the CCB after each LCT

External Pre-Trigger

The TMB ignores any patterns it sees, and waits for an "ext_trig" signal to come from one of several sources (see table below)
Causes trigger of all CFEBs on the CSC
TMB can be programmed to request an L1A from the CCB after each LCT
The OSU Test Control Board (TCB) can provide 40 MHz clock and synchronized external triggers for beam tests

9U VME board with ECL/NIM external trigger inputs
Outputs suitable for TTC and/or up to 3 CCBs
Can generate random LCTs and/or L1As with adjustable average rates
Provides adjustable delay for L1A latency
LHC orbit signals available

External LCT Pre-Trigger Sources	Scope	Useful Functions	Useful Environment
DMB-TMB (dmb_ext_trig) <backplane signal> --initiated by CCB signal (dmb_cfeb_calibrate) via TTC or CCB-VME --followed by auto-L1A from CCB	crate via VME or global via TTC	calibration/test/debug/pedestal	FAST, beam test or LHC
CCB-TMB (a/clct_ext_trig) <TTC B-Go> ?? --set alct/clct/both via VME/slow control? --set TTC B-Go via front panel or VME?	global via TTC?	test/debug/pedestal or scintillator muon	FAST or beam test; needed at LHC?
CCB-TMB (alct_ext_trig) <CCB front panel>	crate	test/debug/pedestal or scintillator muon	FAST or beam test
CCB-TMB (clct_ext_trig) <CCB front panel>	crate	test/debug/pedestal or scintillator muon	FAST or beam test
CCB-TMB (alct_ext_trig) <CCB VME>	crate	test/debug/pedestal	FAST, beam test or LHC
CCB-TMB (clct_ext_trig) <CCB VME>	crate	test/debug/pedestal	FAST, beam test or LHC
VME-TMB (vme_ext_trig) <VME instruction>	CSC	test/debug	FAST, beam test or LHC

Useful LCT and L1A Combintations:

Suggested Trigger Operation Modes	Purpose	LCT Mode	L1A Mode
Normal Mode, usually with ALCT/CLCT coincidence, but ALCT or CLCT only mode available for debug --use 2-layer LCTs for minimum bias tests and timing	Operation in LHC-like mode	Pattern LCT	External source via TTC or CCB Front Panel, like scintillator or L1-Trigger
Semi-Normal Mode, any ALCT/CLCT combination --How does DAQ know about a muon auto-L1A?	Pure LCT-L1A muon sample; Buckeye-LCT pattern testing? Care required in multi-crate mode!	Pattern LCT	TMB requests L1A from CCB for every valid LCT pattern
Trigger Test Mode, external ALCT/CLCT/Both --Scintillator LCT via CCB Front Panel or TTC?	Test LCT function/efficiency	External LCT	External (scintillator) via TTC/CCB or from CCB via TMB L1A request?
Calibration Trigger, (signal dmb_cfeb_calibrate0) --pulse/trigger sequence initiated by TTC/CCB --LCT requested by DMB --L1A requested by TMB --configuration beforehand via slow control	CFEB-Buckeye calibration	TMB via DMB LCT request <on backplane>	CCB via TMB L1A request
Pattern Trigger, (signal dmb_cfeb_calibrate1) --pulse/trigger sequence initiated by TTC/CCB --LCT requested by DMB? Not if testing LCT? --L1A requested by TMB? Only if pattern found? --configuration beforehand via slow control	Test LCT function/pattern recognition; CFEB channel live test?	Pattern LCT?; TMB via DMB LCT request <on backplane>?	TMB requests L1A from CCB for every valid LCT pattern(?) or after DMB requests LCT from TMB(?)
Pedestal Trigger, (signal dmb_cfeb_calibrate2) --like Calibration, but no pulse generated	CFEB noise test	TMB via DMB LCT request <on backplane>	CCB via TMB L1A request

Revision Summary:

12 April 2002: Original version (J. Gilmore, gilmore@mps.no_.-more-._spam.ohio-state.edu)