• Main INDEX
  • Monthly INDEX
  • PREV
  • NEXT

    User name R. Michaels

    Log entry time 13:39:05 on November15,2001

    Entry number 77256

    keyword=fastbus synch problems

    When we started running without ROC14, we saw a nasty surprise: many
    fastbus synch errors reported by ESPACE. I investigated this with the code
    in ~adaq/synch. For both runs 2172 and 2173 there were approx 2000 missing gate
    events, and about 200K events possibly corrupted by extra gates. All this on ROC2.
    Missing gates affect TDC 1875 in 4th slot, perhaps the gate is too wide ?
    Extra gates affect the 22nd and 23rd slots only, it seems.

    For now the experiment is running the "withROC14" configuration.
    I have modified "E00102" to run UNBUFFERED mode which means
    fastbus is read and cleared every event. You can try it if you feel brave.
    ----
    Also I checked 13.8 Million events over runs 2153 - 2169 and found 1 extra
    gate (implying 100 possibly bad events since the synch is checked only every
    100 events) and zero missing gates. Ok ! See also ~adaq/synch/README

    Output of 'synch' for run 2172
    Finished. Num events analyzed = 956613
    Buffered ? 1 (0 = no, 1 = yes)
    Number of missing gate events = 1800
    Number of extra gate events = 180800 (groups of 100)

    Slot Distribution of Extra Gates for ROC 1
    0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
    Slot Distribution of Extra Gates for ROC 2
    0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2043 2043 0 0 0