A CODESYS controller is not a monolithic appliance — it's a SoC + Linux +
software runtime + control app, built along two independent tracks (the Yocto
device platform by the OEM, the IEC 61131-3 control application by the machine
builder). Add an "Anatomy" section to the PLC guide: the classic-vs-soft-PLC
table, a Mermaid diagram of the two development tracks converging on the running
device with the artifact→scan mapping, and a callout on where Yocto fits (the
firmware layer, its own artifact). Explains why PlcSps is a composite target.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>