Download
1 / 9
90 likes | 177 Views
Summary on timing the Velo. Preparing for Possible beam in 22.Aug.2008. Next week. Starting on Friday 22 nd a injection test could provide particles that can excercize our timing startegies. The signal from the BPTX can provide a trigger to the beam passage: already connected to TFC.
E N D
Summary on timing the Velo Preparing for Possible beam in 22.Aug.2008
Next week • Starting on Friday 22nd a injection test could provide particles that can excercize our timing startegies. • The signal from the BPTX can provide a trigger to the beam passage: already connected to TFC. • The SPD is planning to take data and provide a trigger Feedback to Odin.
The Plan • Take BPTX (Beam Pickup Trigger Experiment) and relate to the L0A arrival to the Beetles. T0 Beam passage time TBPTX deltaT0 Known deltaT1 Known L0A generated by Odin L0A Arrival to Beetles deltaT2 Known Set this to 4 us! deltaT3 Data cables. deltaT4 Measure Data arrival to the TELL1
Using SPD? • If The SPD know their time difference between their L0A generation and the time they see the particle signals, we could do the same exercise to find the signals in our detectors.
Timing • Minor changes to the overall configuration of the CBs and TELL1s should be applied as soon as possible in order to have the digitization time checked and commissioned. • The changes in practice: • TELL1 TTCrx Coarse delay = 7CLK , fine delay = 12 ns • TELL1 Cycle delay = 1 (in general) • CB TTCrx Coarse delay = 7 CLK, fine delay = 12 ns. • CB Delay = 12 ns • After these changes we should re-optimize the ARx Sampling time of all links and re-commission them. • Most of the delays in the VELO system were mapped and some diagrams are attached to the end of this talk.
Longer term Developments:Fine Tuning. • For the not so short term some timing scans are still to be implemented in PVSS: Olaf, me (Kazu) and Karol agreed to work on it. • The analysis (VETRA) of such scans has to be written. Checking the time alignment data format. • At the moment that seems not to really work: the time alignment behave as a single event with the consecutive samples…
VELOCB TO = Odin generated L0A TCBin = T2+250ns FiberCB ~ 50 m (250ns=10CLK) Electro optical Translation, Optical spliter ODINFast Signals: Reset, TestPulse, Clock, Trigger TCB1 = TCBin+TTC delay (up to 15+ (0-239)/240) CLK Initially to be set at: TCB1 = T2 + 7*Coarse + 12ns fine TTCrx T2 = TO+ TTCtx+TTCoc+etc. = T1+47ns FiberTL1 ~ 20 m (100ns=4CLK) VeloCB FPGA TCB2 = TCB1 + CB FPGA Delay TCB2 = ? TTELL1 = T2+Fiber Delay = T2+100ns TTCrx TModule = TCB3 + ctrl cable delay = T1+ ~ 2CLK (optic) + 10 CLK (fibre) + 7 (TTCrx coarse) + 12 ns (TTCrx fine) (1/2CLK) + ? (VeloCBFPGA) + 12 ns (Delay25) (1/2 CLK) + 4 CLK (ctrl cable) ~ 16 CLK (fix) + 7 CLK (adjstable) + 25 ns (fine adjustable) L0A CLK CLK, L0A Coarse delay 0-FF? Cable Delay x6 Phy Delay Coarse delay 0 to 2 (1) TCB3 = TCB2 + Delay25 delay. Initially to be set to TCB3 = TCB2 + 12 ns Cycle Delay25 FEM Fine Delay 0-16*1.56 ns Module dataValid Same Beetle Response ARxs TArx 20 m = ~4 cycles Tdatain = Tdataout + 12-15CLK (analog cable delay) TArx = TTELL1 + TTCrx delay + CableDelay + Cycle Delay +PhyDelay = ~ [4 (fibre) + 7 (TTCrxdelay) + 23 (cable/ Adj)+ 1 (Cycle/Adj)] CLK + 12 ns (fine TTCrx) + PHY (Adj) 60 - 75 m = ~12-15 cycles Tdataout = TModule + + Beetle Response (~1,2CLK?) Finally TArx = Tdatain!
159 160 161 162 163 pipeline TBx TL0 =TTrig+TL0DU (2000 + 500 ns, 100 CLK) Beam passage Ext Trigger L0DU ODIN L0A TTrig =TBx + TExt ==? TCBin = TOdin + fiber (50m = 250 ns) TOdin = TL0 + Opt (25 ns) + 200 processing + Latency (Adj) TTCrx VeloCB delay25 T0 =TBx + TOF TMod = TCB (Adj) + CB cable (20m = 100 ns) = T0 + TExt +TL0 (2500 ns) +TOdin (225ns) + OdinLat (N*CLK) + 50m (250ns) + CBTTCrx (0-15 Coarse + Fine) + CBDelay25 (0-31.5 n fine) + 20m (100ns) = T0 + ? + (3075ns Fix) + CoarseAdj +Fine. = T0 + 4000 ns (Beetle lat = 160) TELL1 TP time = 160 + L0A Data 160 = Latency programmed on the beetle.
