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Controls

The scaler-counted raster, the Maia fly-scan, the motion controller, and the seam between CORA and the floor.

Raster mapping

XFM acquires an XRF map by rastering the UTS stage while counting the detectors against the SIS3820 scaler. Two modes appear in the profile: a step grid (bp.grid_scan over the stage, counting the Xspress3 and the scaler per point) and a Maia continuous fly-scan (the stage moves continuously while the Maia array reads against its own encoder feedback). There is no separate hardware position-capture box in the profile collection; the scaler does the dwell / counting and the Maia handles its own fly timing.

Motion control

The StageMotionController drives the UTS raster stage (and the optics axes); its box model, firmware, and IP are not in the profile collection (DRIVE-1), so it is carried as a MotionController family with the specifics blank.

The seam: CORA and the floor

This is where CORA's design meets the XFM floor. The shape matches the other NSLS-II beamlines'.

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

  • the acquisition: setting the energy, rastering the stage, and collecting the fluorescence detectors per pixel (step or Maia fly), with I0 normalization from the scaler;
  • the choice of technique (XRF mapping, the XANES leg), gated by the trust boundary, and the energy / flux calibrations.

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 UTS stage, the Xspress3, the Maia array, and the SIS3820 scaler;
  • the facility filestore where the per-map data lands. CORA moves it, over the TransferPort, into CORA's own Dataset of record.

So CORA brings one conducting engine to XFM, working over the ports: acquisition over the ControlPort, the per-map reduction (XRF spectrum fitting, element-map assembly) over the ComputePort, and data egress over the TransferPort into the CORA Dataset.

The software systems (Xspress3, the Maia system, the SIS3820 scaler, the nslsii device library) are referenced by PV namespace only, never registered as Assets.