1. DAQ deadtime memo Kaz, Grass 2012/01/04 1

2. Current dead time Dead time measured on 2011/09/29  With TDCmax=4, Deadtime =350 us  With TDCmax=8, Deadtime =690 us  With TDCmax=13, Deadtime =1850 us  In our plan, the TDCmax=9  Dead time < 800us  1K HZ trigger is fine, however 2 Input by Cosmis trigger~ 3000HzEvent RateTS Busy Dummy (no TDC data)~3000 Hz24.5 us None-ZeroSuppression, BLK mode~40 Hz2.15 ms Zero-Suppression by CRL code, address only mode ~200Hz4.2ms Zero-Suppression by CRL code, BLK mode~325Hz2.5ms Zero-Suppression fixed the Data transfer dead time.

3. ROC Name TS2941067538TDC Freq (Hz) TS Dead (ms) Detector C2 H1 H2 C1 H3 H4 P4 C3 - C3 + BranchB1B2B3 B4 Max. TDC 06649941010 91313 3003.15 TDC on.......... 6000 24.68us.6........7301.15.66.......7301.15.66.6.....7241.154 5500 on.66.66.... 4402.07.66.6..66.7201.17.66.6.66667201.17....9.99995001.72.66.9.99995001.72.66.9699994402.07.66.9999993003.15 6100 on Max TDC on 06649941010 91313 3602.46 3

4.  MVME 5500 6TDC for 2.07 ms  0.35 ms per TDC  MVME 6100 6TDC for 1.15 ms  0.19 ms per TDC  MVME5500 increase 76 % of dead time  We should put 5500 in the crates with less TDC 4

5.  With this plan the Max number of TDC is 9  The dead time will be 1.72 ms. 5 ROC Name TS2941067538TDC Freq (Hz) TS Dead (ms) Detector C2 H1 H2 C1 H3 H4 P4 C3 - C3 + BranchB1B2B3 B4 TDC on.......... 6000 24.68us 999995001.72.66.9699994402.07 Max TDC on 06649941010 91313 3602.46 Max TDC on 06649941010 91313 3602.46 MVME 5500 on

6. 320 ns time window for Chambers  The prop tube still need 640 ns time window, but the max TDC in one ROC will be 4. 6 ROC Name TS2941067538TDC Freq (Hz) TS Dead (ms) Detector C2 H1 H2 C1 H3 H4 P4 C3 - C3 + BranchB1B2B3 B4 TDC on.......... 6000 24.68us 4449949997131.19 Max TDC on 044.9949999130.88 Max TDC on 04449949999130.88 MVME 5500 on640 ns time window

7. 7 Beam Channel number TDCs For the Fist Run ROCVME now CPU now TIR St1 Hodos Right21 (4TDC+ 1Trigger recoder+ 5v1495) (5500?) 111 St2 Hodos Right2 V1495 Right1 St2 Chamber Left800122(6+6)222 St1 Chamber Right1152 (1124) 18 (33 for the second run) 2(9+9)222 St3 + Chamber Right784132 (6+7)111 St3 - Chamber Left1184193(6+6+7)222 St3 Hodos Right1 (4 +9*2=22 ~22 TDC dead time) 3(8+8+6) 111 St4 Hodos Right3 St4 Props Right5769 (64 clocks time window, twice the TDC dead time) TS Right3 (latch)1111 Not using 42+14 On it’s way to Fermi2 ? Total 8214 13(15)14(14+?)

8. Conclusion  320ns time window -Chambers  640ns time window – Proptubes  14 MVME6100 CPUs  Software Zero suppression  The deadtime is 880 us.  For the 6000Hz input cosmic ray test  we can get 913 Hz event rate. 8