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    User name R. Michaels

    Log entry time 16:43:17 on September29,2000

    Entry number 48497

    keyword=DAQ/Trigger status

    The following was done.
    1. Put FPP into readout. The "twospect" configuration works
    again. Maybe "pedrun" works too, but I had no time to check.
    2. Adjust all timing for infinite momentum. The problem of ADC
    gate coming late on L-arm was solved. Now it comes 35 nsec
    before the start of the signal. One consequence is that the coinc
    triggers are not split from singles triggers at the trigger supervisor.
    Overlaps (in 10 nsec window) are programmed to T5. One should
    usually ignore the CODA event type now. Instead use the TDC
    latch pattern in ROC1, slot 3, channels 1-12 should be triggers after
    prescaling, and channels 17-29 before prescaling. I will write software
    to check it before end-of-tomorrow. However, CODA event types are a
    good approximation if its a true coincidence, or if singles prescale factors
    are high. Misassignment of event types occur in the wings of random coinc.
    This is unavoidable because of the short delays..... etc.
    3) All the momentum settings are set up (in software). I started to check
    these but did not manage to finish. Now I must go somewhere. One might
    try to run DAQ with different momenta and pulser on, to observe if TC moves.
    I think it does, but did not finish this job.
    4) Someone should check, and possibly adjust, timing of any signal in a
    TDC 1875. If <=60 or >=350 nsec it is very marginal and could be inefficient.
    I will stop by tomorrow.