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PV Name	Purpose	EGU	Limits
LLRF:IN20:RH:LOB_PDES	Desired Phase used by LOB local feedback, users, apps other than beam-based feedback - may be used as readback by LEM	degrees; full range, not delta
LLRF:IN20:RH:LOB_P	Desired Phase for Beam-based feedback only	degrees; full range	none provided- to be calculated by beam-based feedback
LLRF:IN20:RH:L0B_PAVG	actual phase readback (avg of multiple channels): used by beam-based feedback, slc-aware readback arrys,	degrees; full range	none provided

LLRF:IN20:RH:L0B_ADES	Desired Amplitude used by LOB local feedback, users, apps other than beam-based feedback - may be used as readback by LEM	MeV;full range	HOPR, LOPR
LLRF:IN20:RH:L0B_A	Desired amplitude for beam-based feedback only	MeV;full range	HOPR, LOPR
LLRF:IN20:RH:L0B_AAVG	actual amplitude readback (avg of multiple channels): used by beam-based feedback, slc-aware readback arrys,	MeV;full range	HOPR, LOPR

LLRF:IN20:RH:G_L0_FB_CTL	When this PV is ON, beam-based feedback locks out users and other applications from setting L0B_A/P, or L0B_ADES/PDES. Beam-based feedback is responsible for setting this PV ON when starting, setting it OFF when stopping. When this PV is set OFF, the _ADES and _PDES PVs are set to supervisory mode and accept new values from users and applications other than beam-based feedback; _P and _A simply reflect the values of _ADES and _PDES. Whe this PV is ON the _ADES and _PDES PVs are set to closed loop mode, and do not accept new values from users and applications. The _P and _A PVs accept values from beam-based feedback, and their values are reflected in _ADES, _PDES

NOTES

These PV names and usages are a template for L1S and the BC1 energy beam-based feedback
The _A, _ADES, _AAVG give the absolute energy gain of an on-crest electron (they will be calibrated by some external means, mostly using the beam); the units of ADES will be MeV
Phase _P, _PDES, _PAVG values give the absolute phase of the RF w.r.t. the beam (they are offset-corrected so that 0 means on-crest)

RESOLVED:

The local feedback loops will remain on during beam-based feedback and other user or application inputs
The Beam-based feedback takes precidence over other applications and user inputs. when Beam-based feedback is on, other inputs are disabled
the L0B_A, L0B_P PVs will be an absolute value, not a delta.
Both amplitude and phase will be available as an actuator for the Beam-based feedback for DL1. Only one of these will be used at a time

UNRESOLVED: