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achim1 / muonic

A python gui for QNet DAQ card experiments
http://achim1.github.io/muonic/
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Get correct DAQ CPLD frequency #5

Closed GoogleCodeExporter closed 9 years ago

GoogleCodeExporter commented 9 years ago 
http://neutrino.phys.washington.edu/~berns/WALTA/Qnet2/misc/DAQ_output_format.tx
t

     The CPLD clock frequency fluctuates slightly over time, depending on 
     temperature changes and oscillator ageing drifts.  Therefore, in 
     order to achieve high accuracy (+/-50 nsec) in computing the absolute 
     trigger times, the user needs to poll the current CPLD frequency at
     a regular basis (say once every 5 minutes) with command DG (Display 
     GPS data).  If the event rate is high enough (at least 1 event per
     100 seconds) then the CPLD frequency can be computed from the 1PPS 
     counter numbers of consecutive events.

I think this is already implemented in muondecay.py. Should be checked again 
and used for muonic.

Original issue reported on code.google.com by achim.st...@gmail.com on 2 Mar 2012 at 7:50

GoogleCodeExporter commented 9 years ago 
The latest revision of the rc0.1 calculates the CPLD frequency by 1PPS counter 
numbers of consecutive events.

Original comment by achim.st...@gmail.com on 14 Mar 2012 at 3:39