- Add heltec_v4 board: ESP32-S3R2, SX1262, SSD1315 display, native USB,
Vext on GPIO36 (active HIGH)
- Wire up heltec_v3 with real esp-hal peripherals (was a stub)
- V3 and V4 share radio/I2C pins, differ in Vext pin/polarity and
display reset
- Restructure main.rs: cfg_if selects embassy_executor::main (Cortex-M)
vs esp_hal_embassy::main (Xtensa) per board
- Display detection via SSD1306 init in display_task — boards always
provide I2C bus, task exits gracefully if no display responds
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Use nightly cargo + esp rustc (RUSTC override) + -Zbuild-std=core for
Xtensa targets. This avoids the esp cargo's inability to parse modern
crate manifests (edition 2024) while still using esp's LLVM with full
Xtensa support.
Pin proc-macro-crate to 3.2.0 to avoid transitive deps requiring
rustc 1.85+.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Implement full SSD1306 OLED display support:
- Splash screen on boot (1.5s) with project name, version, board
- Dashboard showing radio state, config, counters, RSSI/SNR
- RSSI history sparkline (64-sample ring buffer, 2px-wide bars)
- DisplayOn/DisplayOff host commands routed via dedicated channel
- Pure render functions against generic DrawTarget (no hardware coupling)
- Display on/off control bypasses radio task entirely
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Reverts the removal of heltec_v3 — it's a major board. Xtensa builds
use the esp toolchain (+esp via espup); check-all gracefully skips
boards whose toolchain isn't installed.
Build artifacts now land in firmware/ with readable names like
lora-dongle-rak_4631-release.elf instead of being buried in target/.
DESIGN.md updated with "support all common boards" principle (#10)
and corrected toolchain policy (#11).
Heltec V3 (ESP32-S3) requires the espup Xtensa toolchain fork, which
violates the standard-toolchain-only principle. Removed until upstream
Rust supports Xtensa targets via stock rustup.
Also removes all #[allow(dead_code)] band-aids — unused items are
deleted rather than suppressed. DESIGN.md updated with standard
toolchain principle (#10) and peripheral model (input/telemetry slots).
swaitsandClaude Opus 4.6