A sketch that drives several pins between yields lost every pin but the
first. The 4-bit binary counter example (the most-viewed one in the
gallery) blinked bit 0 and left bits 1-3 dark while the firmware counted
0-15 correctly on serial.
Sequence: pin 2's edge arrives first, finds no V-source (the pin was not
in outputPins when the netlist was built), self-heals via handleMcuEdge
and rebuilds. The pin 3/4/5 edges of that same iteration land while the
rebuild solve is in flight, so they queue in pendingMcuEdges. The drain
then looked them up in the loaded context, found no V_uno_3/4/5, and
dropped them. Those pins never got a source, so their LEDs kept the
build-time current (~0) forever — and since the LED part prefers SPICE
current over the digital fallback, they stayed dark for good.
The drop was deliberate: it stops the self-heal -> tick -> self-heal loop
for a pin wired to nothing. Replace the blanket drop with a per-pin
guard: heal a pin at most once per netlist, then drop as before. The
guard re-arms whenever a rebuild changes the V-source list, so a pin that
becomes drivable later still heals.
Verified in the browser on binary-counter-leds; two regression tests
cover both sides (sibling pin heals, unwired pin does not loop).
Running a multiplexed 4-digit 7-segment clock on ESP32/QEMU froze the
browser for minutes after Run — evaluate probes waited 40-90 s, and before
the first fixes the sim WebSocket eventually died (code 1006) with the page
never recovering. CPU-profiled on staging; four compounding per-GPIO-edge
costs, in profile order:
updateComponentState minted a new components array per edge
------------------------------------------------------------
The store setter rebuilt `components` (and one properties object) on EVERY
edge even when the state didn't change. The breadboard is direct-wired to
13 board pins, so segment toggles produced thousands of store sets per
second; every subscriber re-rendered each time, and the canvas subscription
effect (deps: [components, ...]) re-subscribed all pin listeners in a loop.
Now a no-op guard returns prevState unchanged, and breadboards are treated
as self-managed (they have no visual on/off state to echo).
CompilationConsole re-rendered every log line per editor render
----------------------------------------------------------------
The post-compile console holds hundreds of lines; each render called
Date.toLocaleTimeString per line (~0.2 ms each — it builds a fresh Intl
formatter every call). Profile: 162 s of self time in LogLine over a 337 s
window, in ~150 ms tasks. LogLine is now memoized (entries are immutable),
timestamps go through one shared Intl.DateTimeFormat, and the console
itself is React.memo'd against parent re-renders.
Per-edge full SPICE re-solves
------------------------------
PinManager requested a FULL netlist rebuild+solve on every 'mcu' edge.
Now only the edge that newly classifies a pin as MCU-output triggers the
rebuild (that's what emits the pin's V-source); steady-state updates flow
through connectMcuEdgesToService's per-pin coalesced alterSource path.
The start.ts resolve hook is trailing-throttled (33 ms) for the other
per-edge callers (RP2040, custom chips), the service's pending-edge queue
drains on a 33 ms gap timer instead of replaying back-to-back, and new
edges arriving inside the gap queue instead of soloing a solve.
STM32 / Pi reverse pin-name mappings added to connectMcuEdgesToService so
those boards keep fine-grained updates now that the full-tick storm is
gone (PA0/PC13-style and GPIO-style names never matched before).
wokwi-7segment re-rendered per segment write
---------------------------------------------
element.values now flushes at most every 8 ms per display (trailing write
guaranteed), instead of re-rendering the 32-shape SVG per edge.
Also: CLN (colon) pin support for 7-segment clock faces — wired CLN now
drives colon/colonValue in both the attachEvents path and the QEMU
onPinStateChange path; it was silently ignored, so clock colons never lit.
Verified on staging with the failing project: main-thread probes drop from
40-90 s waits (324 long tasks, 52.6 s blocked in 150 s) to 5-11 ms
(2 long tasks, 179 ms), display shows 12:00 with the colon blinking at
1 Hz from the first seconds after Run.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Re-do the AVR spice-driven digital inputs (reverted in c11c195) the right way so
INPUT_PULLUP buttons keep working. PinManager.updatePort now detects the AVR
internal pull-up (input DDR bit + PORT bit high) and sets the pin pull, so the
netlist stamps the 45k pull-up and an INPUT_PULLUP input reads HIGH at idle.
connectDigitalInputsToMcu drives a pin from the solve only when its net is
source-backed by a RAIL or a COMPONENT card (button switch, divider, cross-board
output) — NOT by the internal pull alone — so INPUT_PULLUP pins wired to
event-driven parts with no SPICE model (rotary encoder, keypad) are left to the
part layer and never clobbered. AVR only; RP2040/STM32 stay on the part-seed
until their pulls are modeled.
The spiceDrivenInputs change (e81450e + f4401cc) fixed plain-INPUT-wired-to-rail
reads but BROKE the far more common INPUT_PULLUP + button-to-GND pattern: the
internal pull-up is not modeled in the netlist, so the input floated LOW and read
as permanently pressed (verified live on the stm32-bluepill-button example).
Revert all the spice-driven-input changes to the pre-fix part-seed behaviour,
which handles INPUT_PULLUP correctly. Proper fix (model the internal pull-up per
board so BOTH patterns work) is a follow-up. Keeps the Pi LED fix.
An Arduino input wired to a power rail read the wrong level: a pin tied to 5V
read LOW, and a button-to-5V read idle-HIGH / pressed-LOW. AVR inputs were never
fed the solved circuit voltage (only the ESP32 had spiceDrivenInputs), so a
bare-rail input had no driver and buttons fell back to a hardcoded active-low
pull-up seed that ignored the wiring.
Enable spiceDrivenInputs on AVRSimulator, and gate connectDigitalInputsToMcu on
a new NetlistBuilder sourcedNets set (rails, GPIO V-sources, pulls, and any net
a component card touches). Only source-backed input pins are driven from the
solve; floating nets are left to the part layer, so event-driven parts with no
SPICE model (rotary encoder, keypad, dialer, dip-switch, stepper) keep driving
their own pins instead of being forced LOW.
The live solver only re-solved on component/wire/board changes, so a runtime
burnout (which changes burntComponents, not components) wouldn't rebuild the
netlist — the burnt part stayed in the circuit until something else changed.
Trigger a re-solve on burntComponents change too. The monitor skips already-
burnt parts, so this converges (one extra solve).
- The live solver now excludes runtime-destroyed components from the netlist,
so a burnt part actually goes OPEN: its current stops and anything it fed
loses power (cascading failure), the way real hardware behaves once a part
burns out. Filter is in CircuitSimulationService.runSolve (no-op when nothing
is burnt).
- The LED's burnout now also marks it in the shared burntComponents set, so a
burnt LED gets the same charred + smoke-badge visual (and is opened in the
solve) as a resistor / capacitor, on top of going dark.
Board-less digital circuits (logic gates + switches + LEDs) run today as ngspice
analog B-sources, which is fragile for deep logic: a 4-bit ripple adder re-solves
but never lights its result LEDs live. This adds an event-driven digital motor
that reuses the multichip-bus settle kernel, so the same engine that boots a Z80
over a chip bus evaluates a gate network exactly and instantly.
Phases 0-2 (project/digital-gate-engine/), all behind ?digitalgates=on (default
OFF — flag off is byte-for-byte the old behaviour):
- digitalGateEngine.ts: buildDigitalNetwork(components, wires) does union-find
over the wires (merging pass-through resistors), identifies the rail/gnd from
the signal-generator, registers drivers (rail STRONG-1, gnd 0, pull resistors
PULL, slide-switch as a pass-gate) and event-driven gates (reusing the
LogicGateParts boolean semantics), settles on busKernel, and exposes
setSwitch / readLed / netOf. Tolerant of both the raw example `type` and the
store `metadataId`. Returns {ok:false} for any non-primitive, so mixed/analog
circuits stay entirely on ngspice.
- digitalGateController.ts + a SimulatorCanvas useEffect: when the flag is on and
the circuit is all-digital, rebuild from the store on switch-toggle / load
(rAF-coalesced) and paint the wokwi-led DOM. CircuitSimulationService.tick()
skips the SPICE solve for all-digital circuits when the flag is on, so the two
motors never fight over the LEDs.
Tests: digitalgate-kernel (22 — single gates -> half/full adder -> 4-bit
adder/subtractor -> exhaustive ADD 256 -> mux/decoder/comparator/parity/
multiplier) and digitalgate-engine-examples (6 — the real gallery data for
and/or/xor/not + the full adder/subtractor). Verified live: ?digitalgates=on
lights the adder's result LEDs that the SPICE path leaves dark. Full suite
2117 pass / 5 pre-existing unrelated fails.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Two related bugs that surfaced as "Vitest worker exited unexpectedly /
Timeout terminating forks worker" on the circuit-simulation-service
test file.
Bug 1 — tick() recursively re-schedules itself in its finally block.
After afterEach disposes the scheduler via __resetMixedModeScheduler(),
those re-scheduled ticks throw "call loadCircuit first", get caught by
the console.warn, and the finally schedules ANOTHER tick. Infinite
Promise loop survives until the worker OOMs.
Fix: add CircuitSimulationService.stop() that flips a `stopped` flag
short-circuiting tick() + handleMcuEdge(). The test harness now
tracks each started service in _activeServices and calls stop() in
afterEach alongside the existing unsubscribe sweep.
Bug 2 — when an MCU edge fires on a pin that's NOT wired into any net
(buildNetlist skips it because netLookup returns null), handleMcuEdge
sees hasSource=false, self-heals by queueing the edge + tick(). The
rebuild still doesn't emit the V-source (no wire), so tick.finally
replays the edge → self-heal again → tick again → infinite loop AT
RUNTIME, not just in tests. A user toggling a digital pin without a
wire freezes the whole circuit simulation.
Fix: in tick.finally's pendingMcuEdges replay loop, check whether
the rebuilt netlist now contains a V-source for each pending edge's
pin. If not, drop the edge silently — a future canvas tick triggered
by adding the wire will pick it up via the normal subscription path.
Also fix the "coalesces an edge with an in-flight full solve" test
fixture: simpleBoardWithBoard leaves pin 9 unwired, so V_uno_9 was
never emitted and the test was racing the (now-bounded) self-heal
rebuild. Replaced with an inline fixture wiring pin 9 → resistor →
GND, mirroring the wired fixture used by the alter+republish test
right above it.
Full vitest --shard 1/2 + 2/2 pass cleanly (1886 tests, 22-29s per
shard) with no worker-exit warnings.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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>
CircuitSimulationService.handleMcuEdge(boardId, pinName, state, vcc)
runs the WASM alter + .op + extract path instead of rebuilding the
netlist. Cached `loadedContext` lets `publishFromLastResult` shape an
ElectricalSnapshot without re-running buildInputFromStore.
Coalesces with the canvas-change tick:
- If a full solve is in flight: edge is queued and replayed after
(so the netlist matches when alter runs).
- Last-edge-wins per pin: edges overwrite the same field, so a
10kHz toggle collapses to whatever was last seen at flush time.
connectMcuEdgesToService.ts wires PinManager.onPinChange events to
the service:
- Subscribes to every Arduino-pin slot (0..63) per board. Per-pin
listeners are no-cost when the pin never fires.
- Coalesces edges per pin in a 16 ms window before calling
handleMcuEdge (60 fps cap, well below per-solve cost of 5-15 ms).
- Re-subscribes when boards change (PinManager instances are
recreated by loadHex / setActiveBoard).
MixedModeSchedulerPort gains onMcuPinChange in the port interface
(was already on the singleton but missing from the contract).
3 new service tests cover:
- initial full solve + alter + republish on edge
- coalescing edges with in-flight full solves
- handleMcuEdge kicks a full tick when no circuit is loaded
11 service tests + 90-test regression suite pass. tsc clean.
Next: E — convergence helpers (.options gmin, op-amp retry) so the
LM358 subckt can finally be enabled in componentToSpice.ts.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
The service is the single owner of the simulation loop. Replaces
the trio of wireElectricalSolver + connectLegacySolverToMixedMode +
connectMixedModeSchedulerToStore once G* lands.
Architecture:
- Depends on PORTS only — SimulatorStorePort, ElectricalStorePort,
MixedModeSchedulerPort. Zero coupling to useSimulatorStore /
useElectricalStore / WASM. Easy to test with fakes (and that's
what circuit-simulation-service.test.ts does).
- Single tick(): build netlist → load → solve → extract → publish.
Coalesces concurrent triggers so rapid store changes collapse to
one trailing solve.
- Domain ElectricalSnapshot type covers nodeVoltages + branchCurrents
+ pinNetMap + timeWaveforms + analysisMode + warnings. Shape
matches what the 12 existing useElectricalStore consumers read.
NetlistBuilder extension: BuildNetlistResult now reports `nets`
(every non-ground SPICE net) and `voltageSources` (every V card the
builder emitted). The service uses these to construct the full
vectorsOfInterest list — every node voltage + every branch current
— so the solver returns the data the legacy consumers want.
Scheduler addition: `setExtraVectorsOfInterest(vectors)` lets the
orchestrator add to the per-pin set. Branch currents (i(v_*))
flow through this hook.
8 service tests cover initial solve, branch current extraction,
re-solve on store change, no-spurious-solve, coalescing, .tran
waveforms, warnings forwarding, error-tolerance.
Next: C1+C2 — extract ADC injection / waveform replay into a
solver-agnostic module that just subscribes to useElectricalStore.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
David Montero Crespo