The LCLS DAQ includes many slowly changing quantities (e.g. voltages, temperatures) that are recorded with software called EPICS. Also, many other non-area-detectors are not yet accessible with the simple "Detector" interface.
We have plans to make all data accessible with the easier "Detector" interface, but until that is complete we support the following older forms of accessing detector information.
from psana import *
ds = DataSource('exp=xpptut15:run=59:smd')
evrFullName = Source('DetInfo(NoDetector.0:Evr.0)')
evrAliasName = Source('evr0')
ebeamName = Source('BldInfo(EBeam)')
es = ds.env().epicsStore()
for nevent,evt in enumerate(ds.events()):
# these next two lines are equivalent (second one uses "alias" name)
evr = evt.get(EvrData.DataV4, evrFullName)
evr = evt.get(EvrData.DataV4, evrAliasName)
# now fetch ebeam BLD ("Beam Line Data")
ebeam = evt.get(Bld.BldDataEBeamV7, ebeamName)
# now access one of the slower "epics variables"
if evr is None or ebeam is None: continue
print evr
print ebeam
print es.value('HX2:DVD:GCC:01:PMON')
break
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