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Controls

The trigger box and the motion controllers, and the seam between CORA and the floor.

Unlike FXI, HXN exposes its motion controllers in the profile collection, so CORA can model them as families (the box models, firmware, and IPs are still pending, DRIVE-1).

Triggering: the Zebra

HXN uses a Zebra FPGA position-capture box (nanoZebra, class SRXZebra, XF:03IDC-ES{Zeb:3}:) to hardware-gate the per-point detector triggers off the scan position during a 2D fly raster, the same position-compare role the Aerotech PSO plays at 2-BM and the Zebra plays at FXI. A fast shutter sits on a second Zebra (Zeb:2). A PandABox is being introduced (67-nano-panda, partly commented in source) as a go-forward timing box; CORA carries it deferred (ZEBRA-1).

Motion controllers

Asset Family Drives
SampleMotionController MotionController Power PMAC (Ppmac:1) for the fine raster axes, plus MC:2-MC:8
NanoPositioningController MotionController Attocube ANC350:1-ANC350:8 for coarse nano-positioning, OSAs, beam stops

HXN names these controllers in source (the PMAC and Attocube boxes), so they are modelled as MotionController Assets with the vendor evident; the box model, firmware, serials, and IPs remain staff questions (DRIVE-1). This is more than FXI exposed, where the controller layer was ops-private.

The seam: CORA and the floor

This is where CORA's design meets the HXN floor. The shape matches FXI's, with HXN's scanning twist.

CORA owns (its Conductor, over the ControlPort):

  • the scan orchestration: emitting a 2D/3D raster trajectory over the fine sample axes, hardware-gated point by point by the Zebra, and reading the multi-modal detector set per point. CORA's Conductor runs this directly; it replaces the beamline's current scan orchestration.
  • the energy change, which co-moves the monochromator and the zone-plate refocus (ENERGY-1).
  • the decision of what to run, gated 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 Zebra position-compare gating (the per-point pulses are generated in hardware off the scan position);
  • the PMAC and Attocube closed-loop stage feedback, the PSS/PPS interlock, and the detector IOCs;
  • the facility filestore where the detectors' raw frames and spectra land. CORA moves them, over the TransferPort, into CORA's own Dataset of record; CORA records the Dataset, it does not adopt the facility's data catalog.

So CORA brings one conducting engine to HXN, working over three ports: raster orchestration over the ControlPort, reconstruction over the ComputePort (ptychographic phase retrieval is the heavier multi-step compute leg here, beyond tomographic reconstruction), and data egress over the TransferPort into the CORA Dataset.

The software IOCs (Merlin, Eiger, Dexela, Xspress3, Zebra, PandA, MCS) are referenced by PV namespace only, never registered as Assets.