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OpenHW Studio Telemetry Architecture & Mode Specification

This document provides a comprehensive architectural overview of the OpenHW Studio Telemetry Pipeline. It defines the complete taxonomy of telemetry modes across the Backend (Silicon Emulation) and Frontend (UI Presentation), detailing exactly how data is harvested, optimized, and consumed by both the Automated Grading Engine and the Developer Console.


1. Architectural Overview

The telemetry system bridges the gap between raw silicon simulation instances running in memory (BaseComponent.ts) and the visual presentation layer rendered in React (TelemetryManager.js).

┌────────────────────────────────────────────────────────────────────────┐
│                        EMULATION THREAD (WORKER)                       │
│                                                                        │
│   ┌──────────────────┐             ┌───────────────────────────────┐   │
│   │ BaseComponent.ts │ ──────────> │          execute.ts           │   │
│   │ (Silicon Runner) │             │ (Worker Orchestration Bridge) │   │
│   └──────────────────┘             └───────────────────────────────┘   │
└────────────────────────────────────────────────────┬───────────────────┘
                                                     │ postMessage ({ type: 'state' })
                                                     │ (99% Lighter via Delta Skip)
                                                     v
┌────────────────────────────────────────────────────────────────────────┐
│                          MAIN THREAD (REACT UI)                        │
│                                                                        │
│   ┌─────────────────────┐          ┌───────────────────────────────┐   │
│   │ SimulatorPage.jsx   │ ────────>│      TelemetryManager.js      │   │
│   │ (Bridge Dispatcher) │          │ (Pure Presentation Formatter) │   │
│   └─────────────────────┘          └───────────────┬───────────────┘   │
└────────────────────────────────────────────────────┼───────────────────┘

                             ┌───────────────────────┴───────────────────────┐
                             v                                               v
              ┌──────────────────────────────┐                ┌──────────────────────────────┐
              │    SimulationConsole.jsx     │                │   window.OpenHWTelemetry     │
              │ (Silent / Clean Visual Logs) │                │    (Background UI Cache)     │
              └──────────────────────────────┘                └──────────────────────────────┘

2. Taxonomy of Telemetry Modes

There are exactly 6 distinct mode definitions in the codebase, divided evenly into 3 Backend Data Modes and 3 Frontend Presentation Modes.

A. Backend Data Modes (Silicon Harvesting)

Backend modes dictate what raw mathematical data the Web Worker extracts from silicon instances in memory. These are invoked by execute.ts during keep-alive heartbeats and grading snapshots:

Backend ModeSilicon Method InvokedReturn StructurePrimary Purpose
deepinst.getRawMetrics()Complete diagnostic JSON tree (metrics, heuristics, powerProfile, ioThroughput).Absolute truth anchor for automated grading and headless CLI verification.
deltainst.getDeltaMetrics()Evaluates delta: true/false via fingerprinting (state + stableMetrics).High-performance simulation runs; skips massive metric payloads when stable.
standardinst.getTelemetryData()Baseline sync state and universal metrics without deep heuristic auditing.Standard keep-alive UI heartbeats.

B. Frontend Presentation Modes (Visual UI Formatting)

Frontend modes dictate how the raw data delivered by the worker is formatted and presented in the React diagnostic console by TelemetryManager.js:

Frontend ModeVisual Output StructureBest Used For
detailRich summary string (Freq: 60Hz | Avg: 0.15ms | I/O: I2C(450)) + expandable JSON tree with I/O badges.Deep debugging, bus traffic analysis, and power profiling.
simpleClean, high-level string (State: {"illuminated":true,"brightness":255}) + expandable state object.Quick visual verification of buttons, LEDs, and basic pin toggles.
deltaSilent when idle; pops up [DELTA] State/Metrics updated only when mutations occur.Monitoring long simulation runs for unexpected glitches or state machine changes.

3. The Automated Grading Engine

Which Mode It Uses & Why

The Automated Grading Engine (grading-engine.worker.ts) operates entirely independently of the visual console. It utilizes runner.getRichTelemetrySnapshot({ mode: 'delta' }) and mode: 'deep' as its fundamental verification mechanisms.

javascript
// Inside execute.ts getRichTelemetrySnapshot()
for (const inst of this.instances.values()) {
    if (mode === 'delta') {
        components.push(inst.getDeltaMetrics());
    } else {
        components.push(inst.getRawMetrics()); // 'deep' mode
    }
}

Why This Architecture is Flawless for Grading

  1. Baseline Capture (deep): At the start of a grading run, the grading engine requests a deep snapshot to establish the exact baseline electrical parameters (voltage, power, initial pin states) of the circuit.
  2. High-Performance Delta Loop (delta): During active simulation evaluation, the grading engine requests delta snapshots. If a component is stable (delta: false), BaseComponent.ts still explicitly attaches metrics: full.metrics and state: this.getSyncState().
  3. Cache Recovery: If a delta payload arrives without metrics, the grading engine instantly grabs its cached deep snapshot to fill in the missing metric data. This guarantees that the automated grader always has the complete, flawless electrical profile of every component without degrading simulation speed.

4. The Developer Console & Worker Optimization

Which Mode It Uses & Why

The Developer Console (SimulationConsole.jsx) is powered by TelemetryManager.js, which processes keep-alive state messages emitted by execute.ts (emitStateIfDue).

The Ultra-Lightweight Worker Delta Optimization

To eliminate postMessage serialization overhead and prevent React UI frame drops, collectComponentTelemetry implements a high-performance early return for Delta mode:

javascript
// Inside execute.ts collectComponentTelemetry()
if (effectiveMode === 'delta' && typeof inst?.getDeltaMetrics === 'function') {
    const deltaData = inst.getDeltaMetrics();
    if (deltaData && !deltaData.delta) {
        return { delta: false }; // Ultra-fast early return! Strips out massive telemetryData tree.
    }
}

When a developer sets telemetrySampleInterval = 250 and telemetryMode = 'delta' for a blinking LED, the system behaves with absolute peak precision:

  1. T = 0ms (LED Turns ON)

    • BaseComponent.ts detects a state change (illuminated: true). It evaluates delta: true.
    • execute.ts sends { id: "openhw_led_1", state: {...}, delta: true, telemetryData: {...} }.
    • TelemetryManager.js receives comp.delta === true and prints [DELTA] State/Metrics updated to the console.
  2. T = 250ms (The Sample Interval)

    • BaseComponent.ts notices the LED is halfway through its ON cycle (currentJson === lastReportedJson). It evaluates delta: false.
    • execute.ts hits our early return (return { delta: false }), stripping out the massive metric tree. comp.state is still delivered for canvas UI keep-alive heartbeats.
    • TelemetryManager.js receives { id: "openhw_led_1", state: {...}, delta: false }. It hits the clean console filter:
      javascript
      // In Delta mode, keep the visual console completely clean unless a delta occurred!
      if (telemetryMode === 'delta' && !comp.delta) return;
    • Result: The console remains beautifully SILENT, filtering out redundant stable logs so the developer's screen isn't flooded.
  3. T = 500ms (LED Blinks OFF)

    • BaseComponent.ts detects illuminated flipped to false. It evaluates delta: true.
    • execute.ts attaches the full metric payload and sends delta: true.
    • TelemetryManager.js sees comp.delta === true, bypasses the filter, and instantly prints [DELTA] State/Metrics updated to the console.

5. Summary of Separation of Concerns

  • BaseComponent.ts (Silicon): Source of truth for mathematical state and delta fingerprinting.
  • execute.ts (Worker): Manages CPU/memory efficiency by stripping out redundant metric trees across postMessage while serving unadulterated deep snapshots to the grading engine.
  • TelemetryManager.js (UI): Pure presentation layer that sculpts raw data into human-readable badges, keeping the visual console silent during idle periods while maintaining the background cache (window.OpenHWTelemetry) for external plugins.

Customizable Precision Delta Telemetry

The simulator features a high-performance, parameter-based filtering system for Delta telemetry, allowing users to monitor specific state changes per component instance instead of global updates.

  • Static Telemetry Registry: Powered by telemetryRegistry.js as the source of truth for component parameters, providing O(1) zero-overhead lookups without costly regex/AST parsing at runtime.
  • Per-Component watchedParams: Users can expand per-component menus in the Telemetry Selection Modal (ComponentTelemetrySelectModal.jsx) to choose exactly which state parameters trigger delta events (e.g., watching only illuminated on an LED while ignoring voltageDrop fluctuations).
  • Web Worker Synchronization: The Web Worker (execute.ts & simulation.worker.ts) manages and passes a watchedParamsMap from the UI through to every component runner, constructing state fingerprints dynamically to eliminate 99% of postMessage serialization bloat for non-watched mutations.

Telemetry Reporting Modes & Payload Depths

The simulator implements a highly structured, dual-depth reporting architecture across its three operational telemetry modes (Simple, Detail, and Delta). This ensures optimal presentation clarity in the UI while preserving deep diagnostic capabilities for debugging.

1. Simple Mode (Lightweight State Report)

  • Trigger Condition: Continuous sampling based on telemetrySampleInterval.
  • Payload Depth: Lightweight Report.
  • Mechanics: In formatTelemetryEntry(comp, 'simple'), the engine deliberately strips out the heavy, deep diagnostic trees (metrics, timing, throughput, heuristics). It returns a clean, minimal JSON object containing only active electrical/logical state attributes (e.g., { illuminated: true, brightness: 255 }).

2. Detail Mode (Continuous Rich Diagnostic Report)

  • Trigger Condition: Continuous sampling based on telemetrySampleInterval.
  • Payload Depth: Rich Diagnostic Report.
  • Mechanics: Delivers the complete, unpruned telemetry tree every sample tick. The payload includes state, full operational metrics (update frequencies, idle timing, I/O throughput), active heuristics (health scoring, status summaries), and custom component-specific telemetry.

3. Delta Mode (Mutation-Driven Rich Diagnostic Report)

  • Trigger Condition: Evaluated continuously, but payloads are transmitted only when a watched parameter mutates.
  • Payload Depth: Rich Diagnostic Report (delivered on mutation).
  • Mechanics:
    1. Watched Parameter Filtering: The Web Worker evaluates inst.getDeltaMetrics(inst.telemetryWatchedParams). If none of the user-configured watched parameters have changed, it instantly aborts with { delta: false }, sending 0 metric payloads over the worker bridge.
    2. Full Diagnostic Capture on Change: When a watched parameter does mutate, the worker attaches delta: true along with the complete diagnostic tree (state, metrics, heuristics).
    3. Presentation Formatting: In formatTelemetryEntry(comp, 'delta'), the UI formats details: telemetryData || { state, metrics, heuristics }. Thus, Delta mode provides the exact same comprehensive diagnostic report as Detail mode at the precise millisecond of mutation, allowing developers to inspect the full electrical and timing context surrounding the state change.

Summary of Reporting Structures

ModeTrigger ConditionPayload Depth / Report TypeContents
SimpleContinuous (telemetrySampleInterval)Lightweight ReportPure state attributes only.
DetailContinuous (telemetrySampleInterval)Rich Diagnostic ReportFull state, metrics, heuristics, and custom telemetry.
DeltaOnly on Watched Param ChangeRich Diagnostic ReportFull state, metrics, heuristics, and custom telemetry at the moment of change.

do not edit this part untill aske( for user refrence only)

  1. The Massive Benefits of Stopping Data at execute.ts If we update collectComponentTelemetry to stop attaching telemetryData when delta === false, here is what we achieve:

javascript // What postMessage sends currently in Delta mode (Huge Payload): { id: "openhw_led_1", state: { illuminated: true, brightness: 255 }, delta: false, telemetryData: { _metrics: { ... }, _heuristics: { ... }, vHistory: [...], powerProfile: { ... } }, telemetrySummary: "OK" } // What postMessage will send after your optimization (Ultra-Lightweight Keep-Alive): { id: "openhw_led_1", state: { illuminated: true, brightness: 255 }, // Keeps React canvas LEDs/Screens perfectly synced! delta: false } 🔥 Performance Wins: 99% Reduction in postMessage Overhead: The serialization payload drops from several kilobytes per component down to a tiny 50-byte keep-alive object. Zero Emulation Loop Bloat: The worker thread bypasses building fallback telemetry trees, array cloning (vHistory), and object merging entirely for stable components, allowing the RP2040/AVR core to run at absolute peak simulation speed. Zero UI Memory Thrashing: TelemetryManager.js receives tiny keep-alive heartbeats instead of heavy metric trees, eliminating React thread garbage collection pauses. 3. How We Implement It in execute.ts We can implement your brilliant optimization with a simple, elegant early-return inside collectComponentTelemetry(inst) in execute.ts:

javascript function collectComponentTelemetry(inst: any): any { if (!inst.telemetryEnabled) return {}; // 👑 YOUR OPTIMIZATION: If Delta mode is active and nothing changed, // instantly return delta: false without building or sending ANY metric payloads! if (inst.telemetryMode === 'delta' && typeof inst?.getDeltaMetrics === 'function') { const deltaData = inst.getDeltaMetrics(); if (deltaData && !deltaData.delta) { return { delta: false }; // Ultra-fast early return! } } const out: any = {}; const state = inst.state || {}; ... // proceeds to build full telemetryData only if delta is true or mode is detail/simple This perfectly preserves comp.state for the React canvas UI while completely eliminating telemetry bloat from the worker bridge.

grading

In fact, whoever architected grading-engine.worker.ts literally anticipated this exact ultra-lightweight delta behavior. Here is the rigorous proof of why grading will continue to work flawlessly:

  1. The Built-in Cache Recovery in grading-engine.worker.ts When grading-engine.worker.ts runs, look at lines 377–395 in grading-engine.worker.ts:
javascript
const snapshot = runner.getRichTelemetrySnapshot({ mode: 'delta' });
// 👑 THE SAFETY NET: If delta snapshots omit metrics (delta:false), 
// merge metrics from a deep snapshot once!
if (snapshot && Array.isArray(snapshot.components)) {
    const missingMetrics = snapshot.components.some((c: any) => {
        const customKeys = Object.keys(c?.metrics?.custom || {});
        return !c.metrics || customKeys.length === 0;
    });
    
    if (missingMetrics) {
        if (!deepSnapshotCache) deepSnapshotCache = runner.getRichTelemetrySnapshot({ mode: 'deep' });
        if (deepSnapshotCache && Array.isArray(deepSnapshotCache.components)) {
            const deepMap = new Map(deepSnapshotCache.components.map((c: any) => [c.id, c]));
            for (const comp of snapshot.components) {
                const deepComp = deepMap.get(comp.id);
                if (!deepComp || !deepComp.metrics) continue;
                ...
                comp.metrics = deepComp.metrics; // Merges deep metrics instantly!
            }
        }
    }
}

The Mechanism: When getRichTelemetrySnapshot({ mode: 'delta' }) returns { id, state, delta: false } (omitting metrics), grading-engine.worker.ts detects !c.metrics. It instantly grabs its deepSnapshotCache (which bypasses delta mode by requesting mode: 'deep'), merges the cached metrics directly into comp.metrics, and passes the fully restored object to emitComponentStateEvents!

  1. comp.state Is Always Preserved Even when delta: false, getRichTelemetrySnapshot in execute.ts always attaches state: inst.getSyncState(). Because comp.state (containing illuminated, brightness, voltageDrop) is guaranteed to be present in every single snapshot, emitComponentStateEvents can perform its property-by-property comparison without skipping a beat.

  2. Making collectComponentTelemetry Option-Aware To ensure getRichTelemetrySnapshot({ mode: 'delta' }) communicates perfectly with collectComponentTelemetry, we simply update collectComponentTelemetry to accept optionsMode:

javascript
function collectComponentTelemetry(inst: any, optionsMode?: string): any {
    if (!inst.telemetryEnabled) return {};
    const effectiveMode = optionsMode || inst.telemetryMode || 'detail';
    // If Delta mode is active and nothing changed, instantly return delta: false!
    if (effectiveMode === 'delta' && typeof inst?.getDeltaMetrics === 'function') {
        const deltaData = inst.getDeltaMetrics();
        if (deltaData && !deltaData.delta) {
            return { delta: false }; // Ultra-lightweight keep-alive!
        }
    }
    ...
    ```
And we update getRichTelemetrySnapshot(options) in execute.ts to pass options.mode:

```javascript
snapshot.components.push({
    id: inst.id,
    type: inst.type,
    state: inst.getSyncState(),
    ...collectComponentTelemetry(inst, options.mode)
});

Released under the MIT License.