Drop postcard and serde dependencies entirely. All integers are now
fixed-width little-endian on the wire — no varints, no zigzag encoding.
A developer sending tx_power_dbm=14 sees 0x0E on the wire. No surprises.
- RadioConfig: 10 bytes fixed (freq:4 LE, bw:1, sf:1, cr:1, sync:2 LE, pwr:1)
- Commands/Responses: tag byte + fixed-size fields
- Vec<u8>: 2-byte LE length prefix + raw bytes
- Option<T>: 1-byte (0=None, 1=Some) + T
- COBS framing preserved (just byte-stuffing, no encoding tricks)
- Manual COBS decode replaces postcard's CobsAccumulator
- Removes ~15KB from firmware binary (no serde monomorphization)
Switch all ESP32-S3 boards from UsbSerialJtag to USB OTG CDC-ACM via
embassy-usb. The USB device stack is now shared code — boards only
provide the platform-specific embassy-usb Driver.
- Custom VID:PID 1209:5741 (open-source VID, "WA" PID)
- CDC-ACM class with proper device enumeration
- COBS+postcard protocol over CDC-ACM packet read/write
- Concurrent USB device loop + protocol loop via join()
- On disconnect: sends DisplayCommand::Reset to show "Waiting for host..."
- Justfile: espflash no longer uses --monitor (OTG steals PHY)
- Test script updated to detect by new VID:PID
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Protocol:
- SetConfig, StartRx, StopRx now send Response::Ok on success
(host was timing out waiting for acks that never came)
Display:
- Full frequency precision: 910.525MHz not 910.5MHz
- Full bandwidth labels: 62.5kHz not 62k
- RSSI/SNR row shows units (dBm, dB)
- Separator line moved down 3px to give RSSI/SNR breathing room
- Sparkline is now time-based: each bar = 1 second, scrolls left,
showing ~1 minute of RSSI history. Empty slots = no packets.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Wire up UsbSerialJtag on ESP32-S3 boards for host communication:
- Read COBS-framed postcard commands from host via serial
- Route DisplayOn/Off to display task, everything else to radio
- Serialize responses back to host as COBS frames
- Use postcard::CobsAccumulator for chunked deserialization
- Concurrent read/write via embassy select
RAK nRF52840 USB (embassy-usb CDC-ACM) is still a stub — different
init path, will be implemented separately.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Rebrand from lora-dongle to DongLoRa (portmanteau of dongle + LoRa).
Lowercase donglora in Cargo package name, firmware filenames, and code.
Splash screen shows "DongLoRa" in 9x15 bold.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Root causes found and fixed:
- USB OTG init stole the PHY from USB-Serial-JTAG (the only USB on V4)
- executor-thread feature conflicted with esp-hal-embassy's executor
- Linker flags needed -Wl, prefix for GCC-to-LD passthrough
- Missing exception-handler feature on esp-backtrace
- Missing alloc in build-std
- Missing LTO and codegen-units=1 in release profile
- Vext on V4 is active LOW (datasheet correct, Arduino lib was wrong)
Now matches the official esp-hal v0.22.0 examples exactly.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Three fixes:
- Add .cargo/config.toml with -Tlinkall.x for xtensa target (resolves
ROM functions, interrupt handlers, memory layout)
- Add integrated-timers feature to embassy-executor for ESP32 boards
(resolves _embassy_time_schedule_wake)
- Add `use esp_println as _` to pull in defmt global_logger (was being
stripped as dead code because nothing referenced the crate)
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
- 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>
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).
swaits
