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    User name R. Michaels

    Log entry time 11:40:17 on May19,2009

    Entry number 274745

    Followups:

    keyword=EDTM: attempt swap, continued wierdness

    Per request of the experiment I swapped the EDTM modules on
    R-HRS, slot 1 to 13. Slot 13 remains master (jumpers also swapped).
    Good news is I see no double-pulsing for EDTM. Bad news is I
    still cannot get more than 2.7 Hz. Semi-good news is I can get
    less (seems continuous 0 to 2.7).

    I don't think it's a software problem as I see on vxWorks the
    camac commands. Also I tried typing these commands by hand (see
    below) and could get lower than 2.7 Hz but not higher. The system
    is acting as if there's a problem with the CAMAC library, or
    slot 13 has a problem, or transmission loss of bits, or a higher
    bit is stuck "true" on the module or line.

    Since the EDTM on L-HRS works, I could imagine several hours of
    swapping things around to find the culprit. Not recommended unless
    we are down for a long time. So I give up and I restored all
    cabling. Please check data ! (Scint. ADCs, TDCs, trigger).

    We can have 2.7 Hz or less (maybe need to calibrate the wierd
    prescaling coefficient, at least it seems reproducible), and
    certainly can turn off the EDTM.

    Sample of observations

    Set EDTM prescales to zero. (registers are 7,8,9 for bits
    0xff0000, 0xff00, and 0xff respectively)

    camacEdtCommand(1,13,7,16,0)
    camacEdtCommand(1,13,8,16,0)
    camacEdtCommand(1,13,9,16,0)

    Obtain 2.7 Hz from EDTM

    Setting the higher bits:
    camacEdtCommand(1,13,7,16,100) --> obtain 0.31 Hz
    Reset 7 to 0 --> return to 2.7 Hz
    camacEdtCommand(1,13,7,16,50) --> obtain 0.5 Hz
    Reset 7 to 0 --> return to 2.7 Hz

    Intermediate bits:
    camacEdtCommand(1,13,8,16,100) --> obtain 1.5 Hz
    Reset 8 to 0 --> return to 2.7 Hz

    Setting the lower bits like we normally do:
    camacEdtCommand(1,13,9,16,100) --> no noticeable effect on rate
    camacEdtCommand(1,13,9,16,50) --> no effect

    Again, it's "as if" one of the higher bits were stuck on ...