The canonical "Arduino pin → resistor → BJT base, BJT collector →
load" pattern for multiplexed 7-segment clocks was breaking in the
simulator: getArduinoPinHelper('COM.1') couldn't resolve through
the transistor, so the multiplex-aware 7-segment driver thought no
digit-select pin was wired and fell back to "all digits enabled".
Result: every display in the multiplex array rendered the same
rapidly-changing pattern → user-visible flicker.
Fix: add the NPN/PNP BJTs to the PASSIVE_PIN_PAIRS map with
[collector, base] — the trace function continues from B when it
arrives at C (and vice versa). That makes the Arduino pin driving
the base reported as the controller of the collector — exactly the
relationship the user's multiplex code expects.
Conventions covered:
- NPN (2n2222, bc547, 2n3055): Arduino HIGH → transistor on →
COM pulled LOW → common-cathode digit enabled. Our 7-segment
driver treats "digit pin HIGH = enabled" which matches.
- PNP (2n3906, bc557): inverse logic. We expose the same pin
mapping; users writing PNP-driver code will see the polarity
behave inverted, which is what real hardware does too.
This is a one-line shortcut, not a true active-device model. We're
not simulating BJT saturation, β, base current, or PNP polarity —
just reporting "this Arduino pin is the boss of this collector".
That's enough for the multiplexing use case and the only place
getArduinoPinHelper is consulted today.
Closes the long-standing "components are frozen during simulation"
complaint. Once the user clicked Run, interactive wokwi parts
(pushbuttons, slide-switches, potentiometers …) called
stopPropagation in their bubble-phase mousedown handlers and the
canvas's React onMouseDown never fired — so dragging them to
rearrange the layout was impossible without first stopping the sim.
Two surgical changes:
1. DynamicComponent.tsx switches the wrapper from `onMouseDown` to
`onMouseDownCapture`. Capture phase runs before the inner
wokwi-element, so the canvas sees the mousedown regardless of
stopPropagation downstream. The existing posDiff < 5 check in
mouseup keeps disambiguating click vs drag: a click still falls
through to the wokwi-element's own mousedown/up for button-press
semantics, only sustained movement promotes to a drag.
2. SimulatorCanvas.tsx's touch path used to early-return on touchstart
when interactionRunning + .web-component-container, killing any
chance of a touch-drag. Now we remember the touch's start position
in pendingTouchDragRef and let the browser keep synthesizing mouse
events for the wokwi-element. If the finger drifts past
DRAG_PROMOTE_THRESHOLD_PX (8 px) onTouchMove cancels the
passthrough and starts a real component drag — dispatching a
synthesized mouseup on the original target so the wokwi-element
doesn't stay visually pressed mid-drag.
In digital / analog board-less examples the user clicks a slide-switch
or pushbutton expecting it to flip its state. Until this commit the
component property dialog opened instead and the click never reached
the wokwi-element underneath, so:
- The user couldn't change switch state through the canvas at all.
- With no state change the SPICE solver kept the old netlist, and
every downstream LED stayed dark — the symptom that read as
"voltages change but no LED lights".
Root cause was the gating: SimulatorCanvas only suppressed the
property dialog when `useSimulatorStore.running` was true, but that
flag is bound to an MCU's start/stop. Board-less circuits have no MCU
to start so `running` is permanently false, even when the SPICE engine
has been live since the example loaded.
New derived flag `interactionRunning = running || (boards.length === 0
&& !electricalPaused)` — true whenever the user is in an "interactive"
session, MCU or SPICE-only. Used in three click-handling paths:
- SimulatorCanvas mouse-up handler: dialog is suppressed and the
click falls through to the wokwi-element (line 1395).
- SimulatorCanvas touch-start passthrough: same for touch (line 474).
- SimulatorCanvas touch-end short-tap: same for tap (line 774).
Also propagated to DynamicComponent so the cursor becomes pointer (not
move) for interactive parts in board-less mode — visual cue that the
user can click instead of just drag.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
- Implement HD44780Decoder for decoding I2C commands to HD44780-compatible LCDs.
- Add bmp280_bridge_reader.ino to read BMP280 chip_id and status registers via I2C.
- Create i2c_scanner_multi.ino to scan I2C addresses and report responding devices.
- Introduce lcd_i2c_hello.ino to demonstrate basic LCD functionality with I2C.
- Implement pcf8574_bidirectional.ino to test bidirectional communication with PCF8574.
- Add pico_i2c_master_reader.ino for reading BMP280 from a Raspberry Pi Pico.
- Create rtc_lcd_clock.ino to display time from a DS1307 RTC on an I2C LCD.
- Modified the index file to reflect the new naming convention for Velxio components.
- Changed JSX declarations to use 'velxio-' prefix for various components.
- Updated component overrides to replace 'wokwi-' with 'velxio-' for logic gates and other components.
- Adjusted SVG generation script to use 'velxio-' prefix for BMP280 and Raspberry Pi components.
- Marked submodules as dirty in QEMU and RP2040 libraries.
- Added .prettierignore and .prettierrc.json for consistent code formatting.
- Introduced InstrumentComponent with support for Voltmeter and Ammeter, including pin information handling.
- Implemented a script to inject passive-component preset variants into `scripts/component-overrides.json`, including resistors, capacitors, and inductors with custom names and thumbnails.
- Added a new custom element `<wokwi-capacitor-electrolytic>` representing a polarized aluminum-can capacitor with appropriate SVG representation.
- Updated metadata generation to accommodate new component names and thumbnails for better user experience in the component picker.
- Marked submodules `qemu-lcgamboa` and `rp2040js` as dirty to reflect local changes.
- Decoupled electrical simulation from the simulator store, ensuring SPICE is always active for accurate circuit analysis.
- Removed feature flag for electrical simulation, simplifying the state management.
- Preloaded SPICE engine at app start to eliminate latency during the first solve.
- Added comprehensive tests for MOSFET PWM LED behavior and NPN transistor switch functionality, ensuring correct current flow and response to pin states.
- Implemented diagnostics for floating input nodes in RC low-pass filter circuits, addressing singular matrix issues in SPICE simulations.
- Introduced active semiconductor metadata registry for better component management and simulation fidelity.
- Updated Vite configuration to force re-bundling of local wokwi-elements after component additions.
Adds 44 SPICE mappers, 58 custom metadata entries, and 12 visual
Web Components covering logic gates, transistors, op-amps, regulators,
sources, electromechanical parts and integrated-circuit packaging.
Fase 9 — component catalog expansion
------------------------------------
- 7 logic gates (AND/OR/NAND/NOR/XOR/XNOR + NOT) as SPICE B-sources
- 8 multi-input gates (AND/OR/NAND/NOR with 3 and 4 inputs)
- 9 transistors: 5 BJTs (incl. PNP 2N3906/BC557) + 4 MOSFETs (incl.
P-channel IRF9540/FQP27P06). NMOS refactored from Level=3 W=0.1
(hangs ngspice) to Level=1 with sane W/L
- 5 op-amps: LM358, LM741, TL072, LM324 with per-chip saturation
rails + opamp-ideal
- 4 linear regulators (7805, 7812, 7905, LM317) with dropout
- 3 batteries (9V, AA, coin-cell) with realistic ESR
- Signal generator (sine / square / DC)
- 2 Schottky diodes (1N5817, 1N5819) + photodiode (lux-driven
current source)
Fase 10 — electromechanical + ICs
---------------------------------
- Relay (SPDT): coil + L + S-switch with native hysteresis +
flyback diode, inverted-control trick for the NC contact
- Optocouplers 4N25 and PC817 (LED + CCCS with CTR=0.5 / 1.0)
- 7 74HC ICs as DIP-14 packages emitting 4 or 6 B-sources per
component (first mapper pattern emitting multiple device cards)
- 3 flip-flops (D, T, JK) — digital-sim only (edge detection is
not representable in ngspice .op)
- L293D dual H-bridge motor driver
Infrastructure
--------------
- scripts/component-overrides.json gains a _customComponents[] array
that lets new Velxio-only parts survive metadata regeneration
(previously applyOverrides() could only patch wokwi-elements
components that had already been scanned)
- scripts/generate-component-metadata.ts injects custom entries
before the patch loop
- New ComponentCategory values: 'logic', 'analog', 'electromech'
- frontend/src/components/DynamicComponent.tsx PASSIVE tracing
extended from just ['resistor','resistor-us'] to 9 two-terminal
passives with per-part pin name maps
- New CI workflow test-circuit.yml runs the sandbox on push/PR
- frontend-tests.yml regenerates metadata and fails if committed
JSON is stale
- Documented 2 new ngspice gotchas in circuit-emulation-gotchas.md:
unicode in netlist titles silently hangs the parser, and
MOSFET Level=3 + W=0.1m causes .op to hang
- 164/164 sandbox tests passing in ~9 s (was 88 pre-fase-9)
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
- Implemented SensorControlPanel component to allow real-time adjustments of sensor values during simulation.
- Introduced SensorUpdateRegistry for communication between UI and simulation.
- Added configuration for various sensors including sliders and buttons for user interaction.
- Enhanced existing sensor parts to support updates from SensorControlPanel.
- Created CSS styles for the SensorControlPanel layout and controls.
- Simplified serial data handling in `useSimulatorStore` for both AVR and RP2040 simulators.
- Introduced `boardPinMapping.ts` to map wokwi-element pin names to simulator GPIO/pin numbers for Arduino Uno and Nano RP2040.
- Added `compilationLogger.ts` to parse compile results into structured log entries for better console output.
- Added PWM duty cycle tracking and callback registration to PinManager.
- Introduced methods for handling analog voltage injection and callbacks.
- Updated updatePort method to notify digital pin listeners.
- Improved listener management with clearAllListeners method.
feat: Expand BasicParts with new components
- Registered new components: 6mm Pushbutton, Slide Switch, DIP Switch 8, LED Bar Graph, and 7-Segment Display.
- Implemented event handling for each component to interact with the AVR simulator.
feat: Introduce ComplexParts with advanced components
- Added RGB LED with PWM support for color mixing.
- Implemented Potentiometer and Slide Potentiometer for analog input.
- Created Photoresistor Sensor to simulate light levels.
- Developed Analog Joystick for two-axis control and button press.
- Added Servo motor simulation with pulse width modulation.
- Implemented Buzzer using Web Audio API for sound generation.
- Created LCD 1602 and 2004 simulations with command/data processing.
- Updated components-metadata.json with new generation timestamp.
- Added event handling for button presses and releases in DynamicComponent.
- Improved ExamplesGallery with new styles for placeholders and previews.
- Introduced LCD 20x4 display example with corresponding code and wiring.
- Enhanced SimulatorCanvas to subscribe components to pin changes.
- Implemented PartSimulationRegistry for managing component simulation logic.
- Added basic and complex parts simulation including pushbuttons, LEDs, and LCDs.
- Created utility functions for capturing canvas previews and generating SVG previews for example projects.
- Created a new TypeScript file for component metadata types defining structure for dynamically loaded components.
- Implemented a metadata generator script that scans the wokwi-elements repository to extract component information, including properties and categories.
- Added package.json and package-lock.json for dependency management, including TypeScript and related tools.
- Introduced a new file to log ping statistics for testing purposes.