Controls

The control stack, the scan path, and the autofocus loop. Design-phase; handles not yet assigned.

2-ID runs on the APS EPICS control stack, the same floor as the 2-BM pilot, with a Bluesky RunEngine submitting the raster over the EPICS scanRecord. CORA observes that floor and, where it replaces EAA's scan and autofocus orchestration, conducts over it; it does not replace EPICS itself.

Device handles

CORA models each device's control handle as an opaque string set at the edge. The EAA corpus does not publish PV handles, drive crates, or IOC hosts: its 2-ID-D launcher is a simulation, and the aps_mic integration addresses devices by short registry keys (samy, samz, zp_z), with the concrete PV strings living in beamline startup files the corpus does not include. So every device's handle is left empty in the descriptor rather than filled with an invented value. Wiring each Asset to a real handle is tracked by CTRL-1 on Open questions.

The scan path

The raster is a Bluesky scan over the EPICS scanRecord: a 2D fly raster (fly2d) or a 1D step scan (step1d), with the sample stage moving and the fluorescence detector and flux monitors read at each point. This is the sequencing CORA's Conductor takes over from EAA: CORA owns the Run lifecycle (start, hold, abort, close) and the durable scan state, while the hardware-triggered raster and the scanRecord IOC stay floor.

The autofocus loop

The distinctive control loop is zone-plate autofocus: EAA acquires a 2D map, takes a line scan across a landmark feature, registers it, steps the zp_z focus axis, and minimises the spot width, then applies drift correction over a long scan. In CORA's model this is a conducted, multi-step move-and-measure Run with an agent in the loop: EAA registers as the Agent that proposes each focus step, each proposal becomes a Decision, and CORA's permit and clearance adjudication is the gate the proposed move passes through. EAA's own default-deny posture (operator confirmation required, motion and beam disabled by default) is the shape that gate enforces.

Triggering

The detailed trigger and timing scheme (the detector and stage synchronization during a fly raster) is not published in the corpus and is not modelled here. It joins, as a TimingController device, once the scan hardware and PVs are confirmed (CTRL-1).

Equipment protection

2-ID carries an equipment-protection interlock separate from the personnel PSS, as 2-BM does. CORA does not model the interlock logic; it would only observe outcomes, mapping utility faults to Supply status and device faults to an Asset condition. That mapping is not modelled in this scaffold.