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Controls

The conducting engine that runs the energy scan, the motion controller, and the seam between CORA and the floor.

The energy scan

BMM's measurement is an energy sweep: step (or glide) the monochromator Bragg angle across an absorption edge, and read the ion chambers and fluorescence detector at each point. CORA's conducting engine owns that sweep, over the ControlPort: set the next energy, wait for the optic to settle, read the per-point detectors, advance. This is the energy-scan analog of HXN's position raster, and it is the first real consumer of the energy_scan Capability the catalog anticipates (see Techniques).

Motion controllers

Asset Family Drives
EndstationMotionController MotionController the XAFS sample table (MC:09) and endstation stages

The controller PV (MC:09) is in source; its box model, firmware, and IP are not (DRIVE-1).

The seam: CORA and the floor

This is where CORA's design meets the BMM floor. The shape matches FXI's and HXN's, with BMM's energy-scan twist.

CORA owns (its conducting engine, over the ControlPort):

  • the energy scan: sweeping the monochromator energy and reading I0/It/Ir and the fluorescence detector per point. CORA's engine runs this directly; it replaces the beamline's current scan orchestration.
  • the batch loop over the sample wheel (index a sample, scan, advance), governed by the trust boundary.

CORA drives through (the floor it actuates and observes, and does not replace):

  • the EPICS IOCs via the ophyd hardware abstraction: the ControlPort boundary;
  • the monochromator Bragg drive and feedback, the mirror benders, the PSS/PPS interlock, and the detector IOCs (quad electrometer, Xspress3);
  • the facility filestore where the per-scan data lands. CORA moves it, over the TransferPort, into CORA's own Dataset of record.

So CORA brings one conducting engine to BMM, working over the ports: the energy scan and the wheel loop over the ControlPort, any EXAFS data reduction over the ComputePort, and data egress over the TransferPort into the CORA Dataset.

The software IOCs (Xspress3, QuadEM, Struck) are referenced by PV namespace only, never registered as Assets.