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User name R. Michaels
Log entry time 15:29:36 on September 8,2010
Entry number 332115
This entry is a followup to: 332102
keyword=scaler gating by TS
The gating of normalization scaler (L-HRS only) is controlled by
the trigger supervisor now, such that the scalers count only during
a run. See fig 1. Obviously, the sequence Prestart, Go is done
by CODA when you type "Start Run".
Reminder, the helicity-gated scaler is also gated by the helicity
period, such that during a helicity transition it does not count.
So, the helicity-gated scaler gets a gate which is AND'd in the
appropriate way with the TS. Another reminder: the helicity
gated scaler data are from two "virtual" scalers (in VME software)
formed from one "real" scaler (harware unit). Because of a delay
from the predictor algorithm, there will be a time lag of order
0.03 sec (30 bits / 1000 Hz) if at 1kHz helicity flip rate.
This should not be too important, but is recoverable if necessary.
How to recover/check : using ring-buffer = data from a subset of
channels for each helicity period available in ROC11.