Change Note 2026-09-02

Entity Component System (ECS) for real-time control – evaluation round 3: partitions and observations

ECS for Control – Round 3

The third round of the Entity Component System (ECS) evaluation for real-time control programs. Two things were built this round: partitioning – the program divided into four partitions, each with its own store, meeting only through transports – and observations – a calibrated detection-and-adaptation loop in which the program watches one of its own facilities and adjusts a System's pace in response, verified on target by an authored test suite. The round comprises one example program, EcsControlWatch, and nine documents in the same section; the second round's set stands unchanged as its record.

This remains evaluation work, not part of the core framework.

The documents:

• ECS for Control: Concepts – the architecture, platform-neutral; the third edition of the concepts document.

• ECS for Control: Implementation – the second edition: the constructs the program is built from, and – new in this edition – which enforcement tier holds each rule: the language, the construction gate, or review.

• EcsControlWatch – the EcsControlWatch program: its partitions, its world, its Systems, and what it does on the bench.

• ECS for Control: Round 2 Retrospective – the round-2 outlook tracked against what this round delivered, verdict by verdict – with the round's lessons folded in as a section.

• ECS for Control: Round 3 Outlook – where the evaluation goes next.

And a new document kind, the capability set – four documents covering one capability from concepts to verification:

• ECS for Control: Observations – Concepts – Observations: what per-event detection cannot see, and the apparatus that can.

• ECS for Control: Observations – Calibration – the declared specification and everything derived from it: thresholds, detection curve, recovery horizons.

• ECS for Control: Observations – Implementation – the apparatus in the program's code, from tallying at the source to the supervisor's commands.

• ECS for Control: Observations – Verification – the test suite: every run predicted first, every record compared character by character, on target.

Example Program

• EcsControlWatch is in <repo>/examples/v3.2/rpi/pico2/EcsControlWatch/EcsControlWatch-v21, for the RP2350 (Pico2), based on lib/v3.2.

• The example is self-contained together with its own lib directory, which carries the evaluation's candidate framework material; the installed lib/v3.2 is untouched.

• The verification suite ships with the program – the test tables, the alternative supervisor policies, and the shipped configuration are all in the source tree, re-runnable.

• The program compiles and runs on the target hardware (Pico 2, RP2350).

Last updated: 2 September 2026