Closes the deferred Phase 3.3. Root-causes the Pi 2 "Attempted to
kill init" panic as `mount /dev/vda` failing with EINVAL — Debian
armmp does not have ext4 builtin (only fuseblk in /proc/filesystems).
- qemu_manager: PI_CONFIGS gains raspberry-pi-zero / -1 / -2 entries.
All three use the armmp armhf kernel + Cortex-A7 CPU + the mmio
virtio transport (arm-32 virt PCI fails -75 due to missing reg DT
property). Pi Zero / Pi 1 get the small 1-core / 512 MB profile;
Pi 2 gets 4-core / 1 GB. QEMU command builder branches on cfg.bus
for virtio-blk-pci vs virtio-blk-device (and serial likewise).
- manifest.json: new `raspberry-pi-armhf` image_set wiring three
assets (kernel + initramfs + zstd rootfs).
- Frontend BoardKind gains the three new kinds + an isPiBoardKind()
helper. Replaces the eight scattered `=== 'raspberry-pi-3' ||
=== 'raspberry-pi-4' || === 'raspberry-pi-5'` branches in
useSimulatorStore, Interconnect, loadExample, boardProtocols.
ComponentRegistry gets three new picker entries.
- board-kinds-coverage test: ACCEPTED_UNCOVERED gains the new kinds
(backend boards have no canvas examples).
The matching armhf build-pi-kernel.sh / build-pi-rootfs.sh changes
live in velxio-prod's scripts/ (private overlay) — the upstream
kernel build script only knows about arm64; armhf is built in the
private repo because the assets ship through the license endpoint.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Backend: extract per-board config into a PI_CONFIGS dict keyed by
board_type. Pi 3/4/5 share the same arm64 image set (kernel +
initramfs + rootfs) and differ only in QEMU -cpu and -m:
raspberry-pi-3 → cortex-a53 + 1G (BCM2837, ARMv8 64-bit)
raspberry-pi-4 → cortex-a72 + 2G (BCM2711, ARMv8 64-bit)
raspberry-pi-5 → cortex-a76 + 2G (BCM2712, ARMv8 64-bit)
PiInstance now carries board_type so the per-board lookup happens
once at start_instance time. Unknown board_type falls back to
DEFAULT_PI_BOARD ('raspberry-pi-3') instead of erroring out (for
back-compat with older clients).
Pre-warm hook walks every unique image_set in PI_CONFIGS so the
provider only downloads each set once even when several Pi models
are registered.
Frontend:
- BoardKind union gains 'raspberry-pi-4' and 'raspberry-pi-5'.
- BOARD_KIND_LABELS + BOARD_KIND_FQBN entries for both new boards
(FQBN null since they use the Pi VFS + Python toolchain like Pi 3).
- ComponentRegistry inserts two new component metadata entries
cloning the Pi 3 board art with different thumbnail colours.
Tag name reused so the same velxio-raspberry-pi-3 web element
draws the board on the canvas — the 40-pin GPIO layout is
identical across Pi 3/4/5.
- boardProtocols.ts: Pi 3/4/5 share the BCM physical→GPIO table
(PI3_BCM) since the 40-pin header layout is identical.
- loadExample.ts: where 'raspberry-pi-3' is special-cased (VFS
ingest, .cpp vs .ino filename), now matches Pi 3/4/5 alike.
- Interconnect.isPi3Bridge() recognises all three Pi family members
so Arduino↔Pi serial routing keeps working.
- RaspberryPi3Bridge constructor gained a boardKind parameter
defaulting to 'raspberry-pi-3'. The WebSocket 'start_pi' message
now ships the actual board kind so the backend knows which
PI_CONFIGS entry to use.
- useSimulatorStore.addBoard wires bridge construction for all
three Pi family members.
Pi Zero/Pi 1/Pi 2 (armhf) come in Phase 3.3 — separate kernel
package + armhf rootfs build, no change here.
Smoke-tested inside the prod container:
Pi 4 (cortex-a72) → reached agetty login on hvc0
Pi 5 (cortex-a76) → reached agetty login on hvc0
Both show 'aarch64' in uname -m.
Closes the remaining gaps in cross-board I2C so any topology of
supported boards (Uno↔ESP32, two ESP32s, Uno↔Uno↔Uno, ESP32-C3
connected to anything, etc.) works end-to-end with all I2C
components including write-only sinks (SSD1306, PCF8574, LCD-I2C).
Implementation (6 phases):
1. **BFS routing in I2CBusManager**: connectToSlave + handleExternalConnect
walk the bridge graph with a visited Set so multi-hop chains
(A↔B↔C with the device on C) resolve transparently. A new
forwarder-device shim is installed at intermediate hops so the
existing handleExternalWrite/Read/Stop machinery routes
through without per-method visited tracking.
2. **Per-peer proxy ownership in Esp32BridgeShim**: replaces the
global _proxiedAddrs Set with _proxiedByPeer Map so concurrent
bridges to the same ESP32 (e.g. wired to both Uno and Pico)
don't wipe each other's proxies on teardown. Interconnect's
per-wire teardown calls clearProxiesForPeer(peerBus) instead of
clearAllProxies.
3. **BFS-aware proxy sync**: syncProxyFromPeer now walks the peer
bus + its transitive bridges, so an ESP32 sees devices on
boards two or more hops away. _peerDeviceLookup keeps a flat
addr → device map for write-forwarding and resync.
4. **Periodic resync (250 ms)**: Esp32BridgeShim runs a setInterval
while any proxy is live, re-dumping each device with
dumpRegisters() and pushing updateProxyI2c only when an XOR-
stride hash changes. This keeps RTC time advancing visible to
ESP32 firmware without flooding the WS pipe with static
calibration dumps. Hash is primed during initial sync so the
first tick doesn't push a redundant identical buffer.
5. **Write-forwarding ProxySlave → peer**: backend ProxySlave
buffers write bytes during the transaction and emits a
`proxy_i2c_complete` event on STOP / repeated-START. Frontend
Esp32Bridge dispatches the event to a new onProxyI2cComplete
callback; the shim replays the byte sequence on the actual
peer I2CDevice via writeByte() + stop(). Makes ESP32 firmware
writes to peer SSD1306 actually repaint the OLED, peer PCF8574
latch updates, peer I2CMemoryDevice register mutations propagate.
6. **ESP32-C3 routed as bridge**: Interconnect.isBrowserSim no
longer claims c3/xiao-c3/c3-supermini — they were already
going through Esp32Bridge per the store's ESP32_RISCV_KINDS
routing, but Interconnect was treating them as browser sims
which broke proxy install. isEsp32Bridge now correctly
includes c3 family + ESP32-S3 + Arduino Nano ESP32.
Defensive: addBoard now disposes any existing shim's proxies
before overwriting simulatorMap entry so test reruns don't leak
timers.
Tests:
- 4 BFS multi-hop tests (i2c-multi-board-slave-gap.test.ts)
- 11 cross-board scenarios + per-peer + write-forward + resync
(i2c-esp32-multiboard-bridge.test.ts)
- 1 real-firmware E2E for write-forward via QEMU (compile +
load + observe proxy_i2c_complete arriving with the byte)
- New sketch fixture: esp32_i2c_write_to_peer.ino
Result: 90 test files / 1295 tests pass / 0 fail.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
- Implemented `i2c-esp32-real-firmware.test.ts` to test ESP32 I2C communication via backend and WebSocket.
- Created `load-example-transitions.test.ts` to ensure proper loading of examples between board-less and board-based contexts.
- Added `CircuitVerificationModal.tsx` to display circuit verification results before running simulations.
- Developed `circuitVerifier.ts` to perform pre-flight checks for circuit safety, identifying potential issues like short circuits and component overloads.
- Introduced minimal ESP32 I2C master sketch `esp32_i2c_writer.ino` for testing I2C transactions.
- 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.
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>
davidmonterocrespo24