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    User name A. Camsonne

    Log entry time 18:25:15 on February 08, 2009

    Entry number 259845

    keyword=Compton work

    I still could not find cable P1 of the pattern for electron detecteur.
    It is supposed to be the true helicity signal, so I plugged a cable out
    from the helicity to P1.
    I looked at the inhibit signal, it had a weird shape most likely due to
    the use of a linear fan in/out instead of a logic.
    So replaced the 740 by a Lecroy 429 A.
    Right now the FPGA of the trigger has the inhibit logic implemented,
    inhibit logic is not completly perfect since a few triggers makes it but
    the DAQ does not crash any more.
    It seem a buffer depth of 150 events works, I will have to try to improve
    the CODA buffer size to improve dead time and maybe switching to larger
    memory CPU can help to take adventage of the full buffer of the module.
    The busy output of the electron trigger was faned out on the VME NIM/ECL
    and sent to the inhibit logic and the usual logic register.