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    User name R. Michaels

    Log entry time 07:07:45 on February 06, 2011

    Entry number 346090

    This entry is a followup to: 346088

    keyword=plan for the DAQ

    Yesterday when I was there, most of my time was spent reviving the
    L-HRS DAQ, so I was slowed down by that.  Not complaining, though.
    Anyway, below is my suggested plan.  I'll be in by 1 pm, but if a
    qualified person wants to get started, this will make us more efficient. 
    1. The bigbite DAQ worked ("test1" config) last time I was there. 
    First thing is to establish it still does, as a baseline. Assuming
    it still does, one should use it to establish that all 4 branches of the
    TS work.  Simply move branch 1 cable to branch 2, then 3, and check in
    each case the DAQ works.  (Obviously, reprogramming the TS in each
    step.)  This proves that we have a working Trigger Supervisor on all
    4 of its branches, which is not obvious at this point.
    2. Checking the RS485 cables: The individual pins should be continuous,
    and not shorted to adjacent.  So, for example, pin 4 should go to pin 4, 
    but not to pin 3, nor to pin 5.  Did you check for shorts ?  It can 
    happen.  In my experience, a newly made RS485 has a fairly high chance
    of being bad, and it's always a wrongly made, or misaligned, connector.
    3. If we have functioning TS and good cables, the rest should be easy,
    since we already know we had 4 working DAQs that ran from local TS.  
    A next thing to check is that we know all the "hardware roc numbers"
    (the jumpers) -- even though we think we do.  And to check that the
    rules for resistor termination on the RS485 are respected: 
    no terminators except for the LAST module on the chain.  This could
    easily be the problem for the HRS and will be the first thing I'll 
    check when I come in (together with noting the hardware roc numbers). 
    I think one can survive randomized resistor termination for short cable
    runs, but for long runs like we have now, it matters more.  
    After 1, 2, and 3 the DAQ should work.  Hopefully by 5 pm.
    - Bob M.

    A copy of this log entry has been emailed to: vasulk,rom,danez,yez,lselvy,camsonne,saw