class THaG0Helicity: public THaHelicityDet, public THaG0HelicityReader

 Default constructor for ROOT I/O

 Initialize global variables

 Read parameters from database:  ROC info (detector map), G0 delay, etc.

 Book a histogram, if requested

 Clear event-by-event data

 Decode Helicity data.
 Return 1 if helicity was assigned, 0 if not, <0 if error.

 End of run processing. Write histograms.

 Set debug level of this detector as well as the THaG0HelicityReader
 helper class.

 Set delay of helicity data (# windows).
 This value will override the value from the database.

 Set average time delay (# channels)
 This value will override the value from the database.

 Set the tolerance in timing when looking for missing quads
 (# channels)
 This value will override the value from the database.

 Set the maximum number of missing quads permitted before
 forcing the helicity calibration to be re-performed.
 (# quads)
 This value will override the value from the database.

 Check for and process timing events
 A timing event is a T9, *or* if enough time elapses without a
 T9, it's any event with QRT==1 following an event with QRT==0.

  NOTE: This presently has NO EFFECT on the helicity processing,
        just provides warning messages if something suspicious
        happens.

 Calibrate the helicity predictor shift register.

 Load the helicity in G0 mode.
 If fGate == 0, helicity remains 'Unknown'.

 Load the helicity from the present reading for the
 start of a quad.
  Requires:  cond!=0 in order to force the quad to advance
             fT0 to be updated and set for THIS quad

 This is the random bit generator according to the G0
 algorithm described in "G0 Helicity Digital Controls" by
 E. Stangland, R. Flood, H. Dong, July 2002.
 Argument:
        which = 0 or 1
     if 0 then fIseed_earlier is modified
     if 1 then fIseed is modified
 Return value:
        helicity (-1 or +1).

 Compare the present reading to the predicted reading.
 The raw data are 0's and 1's which compare to predictions of
 -1 and +1.  A prediction of 0 occurs when there is no gate.

 Set functions that can be used instead of database values