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>
Backend:
- api/routes/compile.py accepts board-specific compile options
and dedups in-flight identical requests
- services/espidf_compiler.py expanded ESP-IDF wrapper with the new
options surface (sdkconfig.defaults.in
template added)
- services/arduino_cli.py honour the new options envelope
- services/esp32_lib_bridge.py thread board options through to QEMU
Tests:
- tests/test_compile_request_dedup.py end-to-end dedup behaviour
- tests/test_espidf_options.py covers the new options parsing
Frontend:
- services/compilation.ts client-side mirror — sends the new
options field on every compile request
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
arduino-esp32 v2.0.17's libraries/WiFiClientSecure/src/ssl_client.cpp:23
wraps its entire body in:
#if !defined(MBEDTLS_KEY_EXCHANGE__SOME__PSK_ENABLED) \
&& !defined(MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED)
# warning "Please call idf.py menuconfig ..."
#else
ssl_init / start_ssl_client / stop_ssl_socket /
send_ssl_data / get_ssl_receive / data_to_read
#endif
Our esp-idf-template/sdkconfig.defaults did not enable any PSK key-exchange
mode, so MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED was never auto-set by
mbedtls and ssl_client.cpp compiled to an empty translation unit. The
companion WiFiClientSecure.cpp still compiled and ended up in
libarduino-esp32.a with dangling references, breaking the link of every
sketch that pulls in HTTPClient or WiFiClientSecure (directly or
transitively).
Reproduced against the user's WiFi + HTTPClient example.com sketch on the
prod server and again locally with ESP-IDF v4.4.7 + arduino-esp32 v2.0.17;
the prebuilt sdkconfig that ships with arduino-esp32 itself sets both
flags, so we just align with that.
After the fix the same sketch links cleanly:
velxio-sketch.bin binary size 0xbf470 bytes ... 25% free
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
A user reported the LEDC PWM RGB example failing to compile. The sketch
calls ledcAttach(pin, freq, resolution) — the one-shot API added in
arduino-esp32 3.x. Our toolchain image pins arduino-esp32 to 2.0.17
(matched to ESP-IDF 4.4.7 + the lcgamboa QEMU ROM), where the API is
the older two-step ledcSetup + ledcAttachPin pair. Sketches written
against 3.x docs hit "ledcAttach was not declared in this scope".
Bumping arduino-esp32 to 3.x means moving to ESP-IDF 5.x, which may
break our QEMU fork. Cheaper fix: ship a compat shim header in the
ESP-IDF project template that defines ledcAttach + ledcAttachChannel
in terms of the 2.x API, gated on `!defined(ledcAttach)` so it
disappears the day we bump.
espidf_compiler.py now injects #include "velxio_compat.h" right after
Arduino.h whether the user explicitly included Arduino.h or we
prepended it ourselves.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Two reports rolled into one sdkconfig change:
1. Beta testers reported "weird serial output" across DHT22, Servo+Pot,
Joystick, WiFi×2, and DualADC examples. The user's Serial.print lines
came interleaved with internal ESP-IDF chatter:
I (53306) gpio: GPIO[4]| InputEn: 1| OutputEn: 0| ...
I (10626) phy_init: phy_version 4791,2c4672b,...
sdkconfig.defaults didn't pin a default log level so it inherited
CONFIG_LOG_DEFAULT_LEVEL_INFO. Set WARN (level 2) so only warnings
and errors leak into the user's serial output. Sketches can still
esp_log_level_set() per tag at runtime if they want verbose.
2. BLE Advertise example failed to compile. sdkconfig had NimBLE
enabled, but arduino-esp32 2.0.17's BLEDevice.h targets Bluedroid.
Switch the stack: enable BT_BLUEDROID + BTDM_CTRL_MODE_BR_EDR_BLE +
BT_BLE so the standard arduino-esp32 BLE library compiles. Sketches
that explicitly include NimBLEDevice.h will not compile under this
config — that's a smaller minority than the BLEDevice.h users.
The runtime side of BLE still depends on stubs in the qemu-lcgamboa
fork; this only fixes the compile path.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
First open-source end-to-end emulation of the AI-Thinker ESP32-CAM
in QEMU, paired with a browser webcam → firmware bridge so users can
develop camera sketches without hardware. Status: esp_camera_init()
returns ESP_OK; OV2640 chip-id verifies (PID/VER/MIDH/MIDL exactly
match the datasheet); GPIO 25 VSYNC NEGEDGE interrupt enabled by
the upstream driver. Final piece (cam_task accepting frames) is in
progress — descriptor walker fix landed in this commit.
Backend (Python/FastAPI):
- simulation.py: camera_attach/frame/detach WS handlers
- esp32_worker.py: ctypes binding to velxio_push_camera_frame +
feature-detection fallback for older DLLs
- esp32_lib_manager.py: forward camera commands to the worker stdin
- esp-idf-template/main/CMakeLists.txt: esp32-camera headers added
via add_prebuilt_library + REQUIRES driver (resolves i2c_master_*
symbols). LED_BUILTIN=2 fallback for sketches that hardcode it.
Frontend (React/TS):
- EditorToolbar.tsx: ESP32-CAM (and the rest of the ESP32 family)
added to isQemuBoard list — Run button now starts the QEMU bridge
for these boards instead of falling through to the AVR path
- useWebcamFrames.ts: getUserMedia → OffscreenCanvas →
toBlob('image/jpeg') → base64 → WS at ~10 fps
- CameraToggle.tsx: header button with status colors + frame counter
- SimulatorCanvas.tsx: render CameraToggle for esp32-cam boards
- Esp32Bridge.ts: sendCameraAttach/Frame/Detach + chunked btoa
- useSimulatorStore.ts: diagnostic log on compileBoardProgram
- components-metadata.json: regen including esp32-cam component
Submodule pointer:
- wokwi-libs/qemu-lcgamboa → ff8eee0 (camera devices commit on
davidmonterocrespo24/qemu-lcgamboa branch picsimlab-esp32)
Investigation + tests in test/test-esp32-cam/:
- 13 autosearch markdown docs (overview, SOTA, OV2640 spec, DVP/I2S
spec, build blueprint, blockers resolved, descriptor walker fix)
- 5 sketches (camera_init, sccb_probe, dma_smoke, frame_roundtrip,
webcam_demo) + 8 live + WS regression tests
- README with the user-facing flow
.gitignore:
- libqemu-*.dll.{pre-camera,new,bak} (rollback points, regenerated)
- wokwi-libs/esp32-camera/ (clone consumed by arduino-esp32 path,
not part of this repo)
Co-Authored-By: Claude Opus 4.7 (1M context) <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>
David Montero Crespo