Exact example target and optional physical plan
Core mode needs no hardware. No physical deployment is verified. Example target: Adafruit product 5477, ESP32-S3 Feather with 4 MB flash and 2 MB PSRAM. Do not substitute the 8 MB/no-PSRAM variant. The optional sensor is Adafruit product 2652 BME280 breakout with STEMMA QT. The required sketch reads neither device. Source access date: September 12, 2026.
| Claim | Value/unit | Primary source and section | Confidence/missing data | Consequence |
|---|---|---|---|---|
| Exact variant memory | 4 MB flash; 2 MB PSRAM | Adafruit product 5477, Description | Documented; physical revision unobserved | Use the manifest's 4 MB/QSPI target |
| Connector signals | SCL, SDA, 3.3 V, GND | Feather Pinouts, STEMMA QT | Documented board interface | Keyed JST SH 4-pin connection is the planned interface |
| Peripheral power | Switchable; enable high | Feather Pinouts, I2C interface/STEMMA QT | Guide uses several power aliases; pinned core must resolve the symbol | Do not copy a generic ESP32 power pin |
| Optional BME280 address | Default 0x77; configurable 0x76 | BME280 Pinouts, I2C Address | Jumper position unobserved | Check the actual board before choosing non-default address |
| Feather BME280 footprint | Sensor not populated by default | Feather Pinouts, BME280 section | Documented | A footprint is not an installed sensor |
| Core board/variant symbols | Pinned by ESP32 core 3.3.11 | Board definitions, variant source | Cross-check the installed source before physical adapter work | Preserve FQBN and inspect actual initialization |
The guide's board-power aliases are an intentional source-reading lesson: select the symbol provided by the pinned installed variant and read its initialization, rather than treating every alias as interchangeable. The final core sketch does not use any of them, so this open physical-adapter detail does not affect the synthetic build.
Optional, documentation-based deployment sequence:
- Record the actual board product/revision, breakout revision, cable, tool versions, and address jumper. With USB power disconnected, connect the keyed STEMMA QT cable. Use USB power only for this exercise.
- Read the pinned variant initialization and manufacturer I2C example. Define a separate physical adapter with initialization success/failure and timestamped temperature output. Select and record a BME280 library version before compiling that extension. Keep the existing policy/parser unchanged. Replace the synthetic output label with an explicit physical source label only in that extension.
- Independently compile the physical adapter. Check sensor initialization failure, finite-value validation, retry interval and the driver's actual timeout behavior; the host scheduler does not prove a bus transaction is bounded. Do not report a stale cached driver value as fresh.
- Only in an authorized physical session, connect a data-capable USB cable, verify Windows enumeration, select the observed port, upload, and record real serial output. Check the board's official bootloader recovery instructions for its exact revision if upload fails.
- Record baseline, missing-at-boot, powered-off reconnect/restart, recovery, threshold change, and a five-minute run. Disconnect USB before changing wiring. Indicator and instrument checks belong in that separate report.
No accuracy claim follows from a plausible temperature. A reference instrument and method would be needed for measurement validation. Host tests do not simulate electronics, USB passthrough, electrical faults or MCU execution latency.