End-to-end pipeline fixes uncovered while auditing the /examples gallery.
Each bug shipped past green unit + snapshot tests because none of those run
firmware + render LEDs. Added scripts/visual-led-test.mjs as a CDP-driven
visual harness that loads each example, runs the simulator, samples
`wokwi-led.brightness`, and asserts toggle / gradient / initial-off
invariants — exits non-zero on any regression.
Frontend simulator
- PinManager.updatePort: new optional ddrMask param. A pin is added to
`outputPins` only if the DDR bit is set, so the PORTx write that
enables INPUT_PULLUP (DDR=0, PORT=1) no longer falsely marks the pin
as MCU output. AVRSimulator now reads DDRB/C/D (0x24/0x27/0x2A on
Uno/Nano, 0x37 on ATtiny85, per-port table on Mega) and forwards it.
- AVRSimulator: pass DDR mask alongside every port-listener fire.
- BasicParts pushbutton{,-6mm}: seed pin HIGH in attachEvents so
`digitalRead()` returns HIGH while idle. avr8js doesn't auto-simulate
INPUT_PULLUP — without this the firmware reads LOW from boot and
thinks the button is permanently pressed (the "LED is always on,
pressing does nothing" UX bug).
- connectMcuEdgesToService: suppress synthetic digital edges on pins
with active PWM, AND subscribe to onPwmChange to re-tick the netlist
on duty changes. Fade-LED now produces a true gradient (6 distinct
brightness levels across a fade cycle) instead of a binary 0/full
toggle.
- CircuitSimulationService.handleMcuEdge: replace single-slot
pendingMcuEdge with a per-pin Map. Multiple pins toggling during the
same in-flight tick used to overwrite each other; now every pin's
most-recent edge replays after the tick. Fixes Traffic-Light RED→
YELLOW→GREEN sequencing.
- NetlistBuilder: new sanitizeSpiceId() helper replaces hyphens with
underscores in V-source names. ngspice's interactive `alter` command
treats `-` as an operator and silently no-ops on hyphenated source
names, so mid-simulation MCU pin transitions stopped propagating
after the first solve. MixedModeScheduler.onMcuPinChange and
CircuitSimulationService self-heal use the same sanitizer so names
stay consistent across emit/alter/lookup. Also added a regex-based
fallback in step 2 so any board pin matching `GND.\d+` canonicalises
to net "0" — ESP32-C3 dev kits expose up to 10 GND pins and the
per-board `groundPinNames` list missed several, leaving wires
floating instead of grounded.
- collectPinStates: emit V-sources only for pins in `outputPins`, not
every wired board pin. Leaves INPUT pins (analog sensors on A0,
pull-down dividers, etc.) free for the SPICE solver instead of being
shorted to 0 V by an ideal MCU V-source.
- start.ts: extended __spiceDebug to also expose outputPinsByBoard +
nodeVoltages + pinNetMapEntries for the visual harness.
- ESP32 / RP2040 / RISC-V / C3 simulators: pass `'mcu'` source flag to
triggerPinChange / setPinState so the new outputPins tracking fires
on those boards too (was AVR-only before).
- useSimulatorStore: stopBoard/resetBoard call pm.resetPinStates() so
outputPins clears between runs; Esp32Bridge.onPinChange passes the
`'mcu'` flag in all three places it's wired.
- types/board.ts: ATtiny85 FQBN `clock=internal16mhz` →
`clock=16pll` (ATTinyCore 1.5.2 renamed the option).
Backend
- esp-idf-template/main/CMakeLists.txt: skip the
`-DLED_BUILTIN=2` fallback for esp32c3 and esp32s3 targets. Both
variants already define LED_BUILTIN in pins_arduino.h via a
self-define macro (`#define LED_BUILTIN LED_BUILTIN` + `static const
uint8_t LED_BUILTIN = ...;`). Pre-defining the symbol from the
command line expanded the static-const declaration to
`static const uint8_t 2 = ...;` — a syntax error that broke every
ESP32-C3 / S3 build (`expected unqualified-id before numeric
constant`).
Examples
- examples.ts: bulk-fix 72 wire endpoints that referenced
`componentId: 'nano-rp2040'` / `'esp32-c3'` etc. (boards that don't
exist on the canvas). Replaced with `'arduino-uno'` (the canvas
board-id convention) and converted `D<n>` pin names to `GP<n>` for
Pico-style boards. Affects pico-blink, pico-i2c-scanner,
pico-i2c-rtc-read, pico-spi-loopback, c3-blink and others.
Tests
- scripts/visual-led-test.mjs: CDP-driven harness. Default suite covers
Blink (single-pin), Button (idle-OFF invariant — catches the
INPUT_PULLUP regression), Traffic-Light (multi-pin sequencing),
Fade-LED (PWM gradient — ≥3 distinct levels), RGB-LED (≥3 PWM pins
driven). Run via `npm --prefix frontend run test:visual` against a
Chrome on `:9222` + vite on `:5174` + backend on `:8001`.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Bug reproduced via CDP probe across 5 Run/Stop cycles: cycle 1
worked (LED toggled), cycles 2-5 LED stayed dark — but exactly the
same code, same canvas, same circuit.
Tracing the live electrical store via __spiceDebug() showed:
cycle-1 after-run: branchCurrentCount=3 (pin13 V-source present)
cycle-2 after-run: branchCurrentCount=2 (pin13 V-source MISSING)
cycle-3..5 after-run: branchCurrentCount=2
The flow:
1. User clicks Run -> board.boards reference changes -> service ticks.
2. runSolve calls collectPinStates(board, ...) to snapshot output pins.
3. collectPinStates was emitting an entry ONLY when pinManager.getPinState(pin)
was currently TRUE. If the pin was LOW at that exact instant
(which is most of the time for a Blink sketch — 50% duty), no
pinStates entry, no V-source card in the netlist.
4. AVR runs, digitalWrite(13, HIGH) fires, handleMcuEdge calls
scheduler.onMcuPinChange -> solver.alterSource('V_arduino-uno_13', 5).
5. ngspice gets 'alter V_arduino-uno_13 dc 5' but that V-source
doesn't exist in the deck. Silent no-op. branchCurrents never
updates. LED stays dark forever.
The 'sometimes it works' impression came from cycle 1: the cold-boot
AVR happened to land on a HIGH state precisely when the tick fired,
so the V-source got emitted and every subsequent edge alter worked.
The other cycles caught the AVR in LOW.
Fix: always emit a digital PinSourceState — with v=0 when LOW, v=vcc
when HIGH — so the NetlistBuilder always produces V_<board>_<pin>
cards for every wired GPIO. alterSource then has a target to bind
to no matter what state the pin was in at solve time.
Verified live via CDP probe (_probe_blink.mjs in working tree):
pin13 toggles 0V<->5V at the Blink frequency
LED anode follows at 0V<->1.838V (matches manual calculation:
(5 - 1.84) / 220 = 14.4 mA forward current through the red LED)
branchCurrentCount = 3 stable across all cycles
The mixed-mode migration's endgame. After this commit there is ONE
SPICE solver path in the codebase — the vendored ngspice WASM via
SolverPort, behind both NgSpiceWorkerAdapter (production browser) and
NgSpiceNodeAdapter (Vitest Node). Zero hybrids; zero legacy left to
maintain.
Deleted production files:
• simulation/spice/CircuitScheduler.ts (200ms-poll legacy)
• simulation/spice/SpiceEngine.ts (eecircuit-engine wrap)
• simulation/spice/SpiceEngine.lazy.ts (lazy code-split)
• simulation/spice/subscribeToStore.ts (legacy solve loop)
• simulation/spice/connectLegacySolverToMixedMode.ts (bridge)
• simulation/spice/connectMixedModeSchedulerToStore.ts (feature flag)
Deleted tests (no longer cover any live code):
• connect-legacy-solver-to-mixed-mode.test.ts
• connect-mixed-mode-scheduler-to-store.test.ts
• spice-rectifier-live-bootstrap.test.ts
Migrated 6 tests off the deleted `circuitScheduler.solveNow` API to
the new `__tests__/helpers/solveInput.ts` (same shape, backed by
NgSpiceNodeAdapter).
`useElectricalStore` rewritten as a pure state container:
• setSolveResult(snapshot) — atomic publish from the service
• paused / setPaused — UI control unchanged
• reset — project unload
• REMOVED: triggerSolve, solveNow, setDebounceMs, scheduler hook
• REMOVED: dependency on SpiceEngine.lazy preload
EditorPage now mounts a single `startSimulation()` from
`simulation/spice/start.ts`, which constructs
CircuitSimulationService + ADC bridge + MCU edge bridge. Four
useEffect calls collapsed to one.
`circuitVerifier.ts` (production) and `runNetlist.ts` use an
environment-aware factory: Web Worker in browser, in-proc WASM in
Node tests. `/* @vite-ignore */` keeps the Node adapter chain
(node:fs, node:url) out of the browser bundle while still letting
Node resolve it dynamically.
Removed `eecircuit-engine` from package.json dependencies.
`collectPinStates` extracted to its own module so the service doesn't
depend on the (now deleted) subscribeToStore.ts.
Verification:
• 1392/1392 tests pass across 103 files (28 pre-existing skips).
• `tsc --noEmit` clean.
• `vite build` succeeds (27 s, only the existing chunk-size
warning that pre-dates this work).
Phase 1c — COMPLETE.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
David Montero Crespo