The project save/load pipeline only persisted a single `board_type`, so
multi-board workspaces silently lost every board except the active one
on save, and wires referencing the dropped boards' IDs orphaned to the
canvas corner on reload. An audit of the production backup found 74/306
projects (24%) with at least one orphaned wire and 174/301 non-trivial
projects whose code was still the default Blink template — strong signal
that users save once and never re-save.
Backend
- Add `boards_json` column on `projects` with idempotent ALTER TABLE in
the lifespan migration list.
- New `FileGroup` schema + `file_groups` array on
ProjectCreate/Update/Response. Legacy `files`/`code` kept for back-compat.
- `project_files.py` now uses `{pid}/{groupId}/{filename}` subdirs via
`read_groups`/`write_groups`. Legacy flat layouts are auto-promoted on
read; legacy single-list `files` only updates the active group, leaving
other boards' files intact.
- `_persist_files_from_body` honors file_groups → files → code priority.
Frontend
- `useSimulatorStore.addBoard` accepts an optional `explicitId` so
saved board IDs can be restored verbatim (wires reference IDs literally).
- New `loadProjectState({boards, fileGroups, components, wires,
activeBoardId})` action: tears down current boards, recreates from the
payload, restores file groups atomically, recalculates wire positions
on the next frame, and refreshes the Interconnect.
- `useEditorStore.replaceFileGroups` for atomic multi-group restore.
- `SaveProjectModal` and `ProjectByIdPage`/`ProjectPage` now go through
`buildSavePayload` / `buildLoadPayload` (handles pre-backfill projects
by synthesising a default board from `board_type`).
Auto-save (#useAutoSaveProject hook)
- 2.5s debounced silent PUT triggered ONLY when an authenticated user
has a `currentProject` with a UUID. State hash detects real changes
vs. UI-only churn; baseline is reset on project load so the just-loaded
state isn't immediately re-saved.
- `beforeunload` flush via `fetch keepalive: true` (supports PUT +
credentials, survives unload).
- Compact status indicator in `AppHeader` (idle/dirty/saving/saved/error).
Backfill script (one-off, idempotent)
- `backend/scripts/backfill_boards_2026_05.py` populates `boards_json`
for legacy projects. Heuristic per project, based on which board IDs
the wires reference:
Case A — wires only ref 'arduino-uno' but board_type ≠ uno:
rename id→board_type and rewrite wire endpoints.
Case B — single-board normal: keep verbatim.
Case C — multi-board: recreate one board per distinct ref, infer
kind by stripping trailing -N suffix.
Also moves any flat files into the active board's group subdir.
Stdlib-only, runs from host or `docker exec`.
Docker
- `Dockerfile.standalone` now copies `backend/scripts/` into the image
so the backfill is callable via `docker exec velxio-app python
/app/scripts/backfill_boards_2026_05.py --apply`.
Verified locally on the restored production backup (363 projects):
33 Case A, 316 Case B, 14 Case C, 135 wire endpoints renamed, 0 orphans.
Re-running the script after apply skips all 363 (idempotent).
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
- Introduced EPaperPanels.ts to define configurations for various ePaper panels including dimensions, refresh rates, and controller details.
- Implemented SSD168xDecoder.ts to handle the decoding of SPI commands for the SSD168x family of ePaper displays.
- Created EPaperPart.ts to manage the simulation of ePaper panels, integrating with the existing simulator architecture and handling events.
- Added example sketches for 2.13", 2.9", 4.2", and 7.5" ePaper displays, demonstrating basic functionality and text rendering.
- Ensured compatibility with AVR, RP2040, and ESP32 platforms, with appropriate pin configurations for each.
- Introduced SVG layout dimensions for Phase 1 (B/W mono) and Phase 2 (colour) ePaper panels, detailing active areas, bezels, and pin layouts.
- Developed a phased emulation plan outlining the architecture and deliverables for different panel types, including SSD168x and UC81xx.
- Created a canonical "Hello, World!" sketch for the 1.54" ePaper panel, ensuring compatibility across ESP32, Raspberry Pi Pico, and Arduino Uno.
- Implemented a pure Python SSD168x decoder to validate SPI command sets and framebuffers against specifications.
- Added tests for compiling the hello-world sketch across supported boards and for the SSD168x protocol to ensure correct framebuffer behavior.
- Implemented handshake tests to validate initial bus state and register responses.
- Created end-to-end tests for Pico W LED blinking using MicroPython firmware.
- Added SDPCM framing tests to ensure proper encoding and decoding of control frames.
- Developed IOCTL tests to verify command responses and state changes in the emulator.
- Established a full lifecycle test for WiFi operations, including scanning, connecting, and packet handling.
- Introduced TypeScript configuration for test files to ensure compatibility and strict type checking.
Fixes the user-reported bug where two RPi Pico W boards wired GP0↔GP1
running SerialPassthrough don't communicate. Replaces the broken
broadcast-style cross-board logic in addBoard (only routed AVR↔Pi3B,
ignored wires entirely, no RP2040↔anything path) with a wire-aware
Interconnect singleton.
Architecture: digital pin transitions are the lowest-common-denominator
abstraction. Each simulator's hardware peripherals (UART/I2C/SPI) and
bit-banging libraries (SoftwareSerial, software I2C) decode the
transitions naturally — propagate the pin and the protocols come for
free. For cross-process boards (ESP32 backend QEMU, Pi3B QEMU) a
byte-level shortcut is additionally enabled on hardware-UART pin
pairs to handle high-baud links over WebSocket latency.
Implementation:
- New simulation/Interconnect.ts singleton subscribes to wire/board
changes via the Zustand store. Handlers per tier: browser-sim →
pinManager.onPinChange, ESP32 → Esp32Bridge.sendPinEvent, Pi3B →
bridge.sendPinEvent. Re-entrancy guard via per-(board,pin) Set.
- New utils/boardProtocols.ts classifies pins (uart-tx, i2c-sda, etc.)
per board kind, used as optimization hint for the byte shortcut.
- types/wire.ts: added signalType field, exports WireSignalType /
WireColorMap (fixes a pre-existing TS import error in wireColors).
- Deleted the bridgeMap/simulatorMap broadcast forEach blocks in
addBoard. Initial board + future boards register with Interconnect
via setInterconnectRuntime + store subscription.
- PinManager.resetPinStates() helper for test isolation.
Tests (16 new files, 96 tests, all passing):
- Per-pair × per-protocol matrix: dual-arduino-digital,
dual-pico-digital, arduino-pico-digital, triple-pico-digital-chain,
dual-arduino-hw-uart, dual-arduino-software-serial,
arduino-pico-mixed-uart, arduino-esp32-uart, dual-esp32-uart,
pi3-pico-uart, arduino-pico-i2c, arduino-arduino-spi,
interconnect-routing, dual-arduino-multi-protocol (UART+I2C+SPI+
digital + concurrent), dual-pico-multi-protocol (UART0+UART1 alt+
I2C0+I2C1+SPI0+digital + 3-Pico star topology)
- Updated dual-pico-serial-passthrough to assert correct behaviour
- Backend test/multi_board_esp32/test_dual_esp32_serial.py for two
real QEMU instances (skip-graceful when lcgamboa lib absent)
Verified: 1107/1107 tests pass, zero regressions, vite build OK.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
- 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.
- Implement `ammeter-waveform.test.ts` to validate AC readings from a sine wave source.
- Create `capacitor-charge-transient.test.ts` to test the charging response of an RC circuit driven by a microcontroller pin.
- Introduce `esp32-rectifier-integration.test.ts` for testing rectifier behavior using QEMU and ESP32.
- Add helper functions in `esp32RectifierE2E.ts` for the rectifier test harness.
- Develop `voltmeter-waveform.test.ts` to ensure correct AC and DC readings from a sine wave source.
- Implement unit tests for waveform statistics in `waveform-stats.test.ts` to validate RMS, mean, peak, and interpolation functions.
- Create `waveformStats.ts` to provide statistical functions for time-domain waveform analysis.
- Implement `serial-batching.test.ts` to verify the behavior of `createSerialBatcher`, ensuring it coalesces multiple appends into a single flush, preserves byte order, and groups by board.
- Create `spice-rectifier-integration.test.ts` to test the end-to-end functionality of the Half-Wave Rectifier example, covering the entire simulation pipeline from input building to circuit solving.
- Add `spice-rectifier-live-repro.test.ts` to reproduce a live-app failure scenario, tracing through each layer of the simulation to identify potential failure points.
- Introduce `spice-signal-generator-tran.test.ts` to validate the behavior of the signal generator and ensure correct analysis type switching based on circuit components.
- Establish `serialBatcher.ts` to implement a batching mechanism for USART output, reducing the frequency of store updates and preventing React's maximum update depth error.
- 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.
Electrical simulation is now active by default (mode='spice' instead of
'off') — users no longer need to toggle the mode on manually. The engine
lazy-loads on first solve, so there is no startup cost penalty.
Changes:
- useElectricalStore: default mode = 'spice' when ELECTRICAL_SIM_ENABLED
- subscribeToStore: ADC_PIN_MAP expanded to all 18 board types (Uno, Nano,
Mega with 16 ADC channels, ATtiny85, RP2040 GP26-29, ESP32/S3/C3 GPIO
ADCs). Voltages from SPICE solutions now inject into MCU ADC peripherals
for all boards.
- BasicParts LED: reads branchCurrents from useElectricalStore when SPICE
is active. Brightness = clamp(|I_led| / 20mA, 0, 1) instead of boolean.
Subscribes to store changes to update in real time.
- ElectricalOverlay: shows per-wire voltage labels (gold monospace on dark
pill) using buildWireNetMap() which replicates the NetlistBuilder's
Union-Find to map wireId -> netName -> nodeVoltage. Summary pill shows
net count + solve time.
- NetlistBuilder: new export buildWireNetMap() for lightweight wire-to-net
resolution without running ngspice.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
- Introduced I2C_SENSOR_MAP for pre-registering I2C sensors in the simulator store.
- Implemented I2C slave state machines for MPU6050, BMP280, DS1307, and DS3231 sensors in esp32_i2c_slaves.py.
- Added unit tests for I2C slave functionality covering BMP280, DS1307, DS3231, and I2CWriteSink.
- Updated the simulator store to handle I2C address resolution and sensor data management.
- Marked submodules as dirty in wokwi-libs for rp2040js and wokwi-elements.
- Implemented _MPU6050Slave and _BMP280Slave classes for I2C communication.
- Enhanced main function to register these sensors and handle I2C events.
- Updated sensor management to support MPU-6050, BMP280, DS1307, DS3231, SSD1306, and PCF8574.
- Added frontend examples for BMP280 weather station and SSD1306 OLED display.
- Modified Esp32Bridge to handle new I2C transaction events.
- Updated ProtocolParts to support ESP32 path for I2C devices.
- Enhanced useSimulatorStore to manage I2C transaction listeners.
Frontend WiFi detection via file-content scanning was unreliable because
fileGroups[board.activeFileGroupId] could be an empty array (not null),
bypassing the ?? fallback to editorState.files.
Fix: the ESP-IDF compiler now returns has_wifi:bool in its compile response.
The frontend stores this on the BoardInstance and uses it in startBoard()
instead of scanning file contents. The file-content scan is kept as a
fallback for boards that haven't been compiled in this session.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
startBoard() was reading useEditorStore.getState().files (the legacy global
array with the default Arduino sketch) instead of the board's specific file
group. This caused hasWifi to always be false for ESP32 boards, so QEMU
never received the -nic flag and WiFi never connected.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
- handleRun now auto-compiles for ESP32/QEMU boards when no firmware is
available (same behavior as AVR/RP2040 boards)
- startBoard now reloads compiledProgram into the bridge if _pendingFirmware
was lost (e.g. after a page refresh between compile and run)
- Adds Esp32Bridge.hasFirmware() helper used by the store check
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Replace arduino-cli with ESP-IDF 4.4.7 for ESP32 compilation — Arduino-compiled
firmware crashes in QEMU (9-28 reboots) while ESP-IDF boots cleanly (0 reboots).
The new espidf_compiler translates Arduino WiFi/WebServer sketches to native
ESP-IDF C code, compiles with cmake+ninja, and merges into 4MB flash images.
Key changes:
- ESP-IDF compiler: translates WiFi.begin/WebServer to esp_wifi/esp_http_server
- ESP-IDF project template with QEMU-optimized sdkconfig (DIO, 40MHz, no WDT)
- WiFi status parser for ESP-IDF serial logs (wifi_status, ble_status events)
- IoT Gateway HTTP reverse proxy for ESP32 web servers
- WiFi/BLE auto-detection from sketch content + visual status icons
- Static IP 192.168.4.15 matching slirp DHCP first-client range
- Docker: new espidf-builder stage with ESP-IDF 4.4.7 toolchain
- 157 tests covering WiFi/BLE for both ESP32 (Xtensa) and ESP32-C3 (RISC-V)
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
- Implemented ExampleLoaderPage to load examples by ID from the URL.
- Added ExampleLoaderPage route to App component.
- Created ShareModal for sharing project links with visibility toggle.
- Updated UserProfilePage to include share button for user projects.
- Enhanced ExamplesGallery with a copy link button for examples.
- Introduced utility function loadExample to streamline example loading and library installation.
- Updated project visibility management in useProjectStore.
- Added styles for new components and buttons.
- Updated .gitignore to include Arduino compilation byproducts.
Extends MicroPython support (Phase 2) to ESP32 Xtensa boards running on
QEMU. Firmware is downloaded from micropython.org, cached in IndexedDB,
and loaded into QEMU. User code is injected via the raw-paste REPL
protocol after the MicroPython REPL boots.
- Create Esp32MicroPythonLoader.ts for firmware download/cache
- Add raw-paste REPL injection (Ctrl+A → Ctrl+E → code → Ctrl+D) to Esp32Bridge
- Extend loadMicroPythonProgram in store for ESP32 path
- Add ESP32 default MicroPython content (GPIO 2 blink)
- Simplify SerialMonitor Ctrl+C/D to work for all MicroPython boards
- Bundle fallback firmware for ESP32 and ESP32-S3
- Add all ESP32 board variants to SerialMonitor tab maps
Closes#3 (Phase 2)
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Implements MicroPython emulation for Raspberry Pi Pico boards running
entirely in the browser using rp2040js. Users can toggle between
Arduino C++ and MicroPython modes via a language selector dropdown.
Key changes:
- Add LanguageMode type and BOARD_SUPPORTS_MICROPYTHON to board types
- Create MicroPythonLoader.ts: UF2 firmware parser, LittleFS filesystem
builder (via littlefs-wasm), IndexedDB firmware caching
- Extend RP2040Simulator with loadMicroPython() method using USBCDC for
serial REPL instead of UART
- Add setBoardLanguageMode and loadMicroPythonProgram store actions
- Update EditorToolbar with language toggle and MicroPython compile flow
- Enhance SerialMonitor with REPL label, Ctrl+C/D support
- Bundle MicroPython v1.20.0 UF2 firmware as fallback in public/firmware/
- Update useEditorStore to create main.py default for MicroPython mode
Closes#3
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Closes#14
- Right-click context menu on boards with "Remove board" option
- Delete/Backspace key removes the active board (when no component selected)
- Confirmation dialog before removal showing connected wire count
- Removing a board also removes all connected wires and cleans up
file groups, simulators, bridges, and VFS
- Cannot remove the last remaining board (button disabled + guard)
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Closes#81
- Add `codeChangedSinceLastCompile` dirty flag to useEditorStore
- Play button now triggers compilation automatically when no compiled
program exists or code has changed since last compile
- Show compilation progress during auto-compile before run
- If compilation fails, show errors instead of running stale code
- Keep separate Compile button for manual compile-only workflow
- Play button always enabled (disabled only while running/compiling)
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
- Added board-agnostic sensor registration methods in RP2040Simulator.
- Enhanced ComplexParts to handle LEDC PWM duty updates for ESP32.
- Updated ProtocolParts to check if the simulator handles sensor protocols natively, delegating to backend if applicable.
- Introduced pre-registration of sensors in useSimulatorStore for ESP32 to prevent race conditions.
- Added tests for ESP32 DHT22 sensor registration flow, ensuring proper delegation and fallback mechanisms.
- Created tests for ESP32 Servo and Potentiometer interactions, verifying PWM subscriptions and ADC handling.
- Updated components-metadata.json with new generated timestamp.
- Refactored Esp32C3Simulator.ts to remove unnecessary debug variables and logging, and added support for additional ROM functions.
- Modified useSimulatorStore.ts to clarify bridge usage for ESP32 boards.
- Updated submodules for QEMU and other libraries to indicate dirty state.
- Added test_esp32c3_emulation.py for end-to-end testing of ESP32-C3 emulation, including compilation, flash image merging, and GPIO event checking.
- Added `onPinStateChange` method to `ChipParts` for handling pin state changes in 7-segment displays.
- Updated `useOscilloscopeStore` to allow independent monitoring of multiple boards by adding `boardId` to channels and modifying `addChannel` method.
- Modified `getOscilloscopeCallback` in `useSimulatorStore` to filter channels based on `boardId` and pin number.
- Adjusted component and board position calculations in `useSimulatorStore` to account for wrapper offsets.
- Updated submodule references for `qemu-lcgamboa`, `rp2040js`, and `wokwi-elements` to indicate dirty states.
- Implemented a simple LED blink program in C for the ESP32-C3, targeting RV32IMC architecture.
- Created a linker script to define memory layout for the ESP32-C3.
- Added build script to compile the blink program using the riscv32-esp-elf-gcc toolchain.
- Developed Esp32C3Simulator to emulate ESP32-C3 behavior in the browser, including GPIO and UART functionality.
- Implemented utility functions to parse ESP32 flash images and handle loading of binary data.
- Included disassembly output for debugging purposes.
- Added necessary test fixtures for the blink example.
- Implemented ATtiny85 visual component with DIP-8 layout and built-in LED.
- Added Raspberry Pi Pico W web component using official SVG and pin mapping.
- Created RISC-V Board visual component with SOP-20 style and built-in LED.
- Introduced RiscVCore class for minimal RV32I ISA interpreter with memory model.
- Developed RiscVSimulator class for CH32V003-compatible simulator with UART and GPIO support.
- Updated subproject commits for qemu-lcgamboa, rp2040js, and wokwi-elements to dirty state.
- Add VirtualFileSystem component for managing files and directories.
- Integrate useVfsStore for state management of the virtual file system.
- Implement context menu for file operations: New File, New Folder, Rename, Delete.
- Add upload functionality to send files to Raspberry Pi.
- Create default file structure for new Raspberry Pi boards.
- Enhance editor with board-aware features and compile/run orchestration.
- Introduce CompileAllProgress component for tracking compilation status across boards.
- Redesign SerialMonitor to support multiple boards with tabbed interface.
- Establish Raspberry Pi specific workspace with terminal and file system integration.
- Updated wire structure to replace control points with waypoints for better handling of wire paths.
- Introduced new utility functions for wire hit detection and rendering segments.
- Enhanced wire creation process to support dynamic waypoints and color assignment.
- Implemented a new ESP32 worker for improved simulation handling.
- Added utility functions for generating orthogonal paths and auto-coloring wires based on pin names.
- Improved compatibility with existing projects by ensuring backward compatibility with wire data structures.
- Added detailed logging for GPIO changes, system events, and errors in simulation websocket.
- Improved ESP32 firmware handling by merging individual binaries into a single 4MB flash image.
- Updated ESP32 bridge to handle serial output and GPIO changes with appropriate logging.
- Introduced integration test for ESP32 emulation, covering compilation, WebSocket connection, and event handling.
- Enhanced examples to include ESP32 projects and updated the examples gallery to reflect new board types.
- Refactored simulator store to manage ESP32 bridge and simulator instances more effectively.
- Updated requirements to include esptool for ESP32 firmware management.
David Montero Crespo