release: firmware v0.2.0

Major architecture reorganization, Wio Tracker L1 support, LED blink
on packet activity, native USB for Heltec V3 (hardware mod required).
See CHANGELOG.md for full details.

CHANGELOG.md

@@ -5,7 +5,42 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/),
 and this project adheres to [Semantic Versioning](https://semver.org/).
 
-## [0.1.0] - Unreleased
+## [0.2.0] - 2026-04-07
+
+### Added
+
+- Wio Tracker L1 board support (nRF52840 + SX1262, SH1106 OLED)
+- LED blink on packet activity: brief flash on RX and TX when display is on
+  - RX brightness scales with SNR (stronger signal = brighter)
+  - Works on all boards with a user LED (Heltec V3/V4, Wio Tracker)
+- Native USB CDC-ACM support for Heltec V3 (requires hardware mod: solder R29/R3)
+- `heltec_v3_uart` feature for stock (unmodified) V3 boards via CP2102 bridge
+- `RgbLed` trait and `SimpleLed` driver for GPIO-based LEDs
+- `LoRaBoard` trait with full associated types (`RadioParts`, `CommParts`,
+  `DisplayParts`, `DisplayDriver`, `LedDriver`) and `BoardParts<R, C, D, L>` struct
+
+### Changed
+
+- Major firmware architecture reorganization:
+  - `hal/` module for MCU-specific primitives (ESP32-S3, nRF52840)
+  - `driver/` module for hardware peripheral drivers (SH1106, SimpleLed)
+  - `host/` module for unified USB/UART communication with internal cfg dispatch
+  - `board/` contains only board definitions — no MCU helpers or drivers mixed in
+  - Board files are declarative wiring diagrams calling hal primitives
+- `run()` function has zero board-specific conditional compilation
+- Display init moved to board layer (`create_display()`) — display task has no cfg
+- Flattened `radio/` and `display/` directories (no single-file directories)
+- `build.rs` auto-discovers boards by content (implements `LoRaBoard`) and
+  helper modules by `use super::` imports — no exclusion lists
+- `check` and `clippy` commands now use `--release` profile
+- Deduplicated USB/UART protocol framing (shared `CobsDecoder` + `route_command`)
+- Removed `ErrorCode::CrcError` (SX1262 silently drops bad-CRC packets)
+
+### Fixed
+
+- Display stuck on splash screen for UART boards (disconnected flag started true)
+
+## [0.1.0] - 2026-03-15
 
 ### Added
 

firmware/Cargo.lock

@@ -372,7 +372,7 @@ dependencies = [
 
 [[package]]
 name = "donglora"
-version = "0.1.0"
+version = "0.2.0"
 dependencies = [
  "cfg-if",
  "cortex-m",
@@ -390,6 +390,7 @@ dependencies = [
  "embassy-usb",
  "embassy-usb-driver",
  "embedded-graphics",
+ "embedded-hal 1.0.0",
  "embedded-hal-async",
  "embedded-io-async 0.7.0",
  "esp-backtrace",

firmware/Cargo.toml

@@ -3,7 +3,7 @@ members = ["."]
 
 [package]
 name = "donglora"
-version = "0.1.0"
+version = "0.2.0"
 edition = "2021"
 build = "build.rs"
 authors = ["Stephen Waits <steve@waits.net>"]
@@ -21,6 +21,7 @@ categories = ["embedded", "hardware-support", "no-std"]
 cfg-if = "1.0"
 critical-section = "1.2"
 defmt = "1.0"
+embedded-hal = "1.0"
 embedded-hal-async = "1.0"
 embassy-embedded-hal = "0.6"
 embassy-executor = "0.9"

firmware/TODO.md

@@ -1,8 +1,4 @@
-- get the code better organized
-- firmware file naming, no "release", add version
 - LED blinking on TX/RX? colored?
-- display having board specific stuff in it
 - publish new client, mux, bridge (updates in client for UART crap)
-- try to get heltec v3 back to the right USB port+VID:PID
 - split out mux and client repos
 - move to GH organization

firmware/src/board/heltec_v3.rs

@@ -11,6 +11,7 @@ use static_cell::StaticCell;
 
 use super::esp32s3;
 use super::traits::{BoardParts, LoRaBoard};
+use crate::driver::simple_led::SimpleLed;
 use crate::hal::esp32s3 as mcu;
 
 pub use super::esp32s3::{
@@ -18,6 +19,7 @@ pub use super::esp32s3::{
 };
 
 pub type UsbDriver = esp_hal::otg_fs::asynch::Driver<'static>;
+pub type LedDriver = SimpleLed<Output<'static>>;
 
 pub struct UsbParts {
     pub driver: UsbDriver,
@@ -35,6 +37,7 @@ impl LoRaBoard for Board {
     type CommParts = UsbParts;
     type DisplayParts = DisplayParts;
     type DisplayDriver = DisplayDriver;
+    type LedDriver = LedDriver;
 
     fn init() -> Self {
         let p = esp_hal::init(esp_hal::Config::default());
@@ -45,7 +48,7 @@ impl LoRaBoard for Board {
         mcu::mac_address()
     }
 
-    fn into_parts(self) -> BoardParts<RadioParts, UsbParts, DisplayParts> {
+    fn into_parts(self) -> BoardParts<RadioParts, UsbParts, DisplayParts, LedDriver> {
         let p = self.p;
 
         mcu::start_timer(p.TIMG0);
@@ -79,10 +82,15 @@ impl LoRaBoard for Board {
         let i2c = mcu::init_i2c(p.I2C0, p.GPIO17, p.GPIO18);
         let display = Some(DisplayParts { i2c });
 
+        // White LED on GPIO35
+        let led_pin = Output::new(p.GPIO35, Level::Low, OutputConfig::default());
+        let led = SimpleLed(led_pin);
+
         BoardParts {
             radio,
             host,
             display,
+            led,
             mac: Self::mac_address(),
         }
     }

firmware/src/board/heltec_v3_uart.rs

@@ -10,6 +10,7 @@ use esp_hal::gpio::{Level, Output, OutputConfig};
 
 use super::esp32s3;
 use super::traits::{BoardParts, LoRaBoard};
+use crate::driver::simple_led::SimpleLed;
 use crate::hal::esp32s3 as mcu;
 
 pub use super::esp32s3::{
@@ -17,6 +18,7 @@ pub use super::esp32s3::{
 };
 
 pub type UartDriver = esp_hal::uart::Uart<'static, esp_hal::Async>;
+pub type LedDriver = SimpleLed<Output<'static>>;
 
 pub struct UartParts {
     pub driver: UartDriver,
@@ -34,6 +36,7 @@ impl LoRaBoard for Board {
     type CommParts = UartParts;
     type DisplayParts = DisplayParts;
     type DisplayDriver = DisplayDriver;
+    type LedDriver = LedDriver;
 
     fn init() -> Self {
         let p = esp_hal::init(esp_hal::Config::default());
@@ -44,7 +47,7 @@ impl LoRaBoard for Board {
         mcu::mac_address()
     }
 
-    fn into_parts(self) -> BoardParts<RadioParts, UartParts, DisplayParts> {
+    fn into_parts(self) -> BoardParts<RadioParts, UartParts, DisplayParts, LedDriver> {
         let p = self.p;
 
         mcu::start_timer(p.TIMG0);
@@ -75,10 +78,15 @@ impl LoRaBoard for Board {
         let i2c = mcu::init_i2c(p.I2C0, p.GPIO17, p.GPIO18);
         let display = Some(DisplayParts { i2c });
 
+        // White LED on GPIO35
+        let led_pin = Output::new(p.GPIO35, Level::Low, OutputConfig::default());
+        let led = SimpleLed(led_pin);
+
         BoardParts {
             radio,
             host,
             display,
+            led,
             mac: Self::mac_address(),
         }
     }

firmware/src/board/heltec_v4.rs

@@ -3,6 +3,7 @@ use static_cell::StaticCell;
 
 use super::esp32s3;
 use super::traits::{BoardParts, LoRaBoard};
+use crate::driver::simple_led::SimpleLed;
 use crate::hal::esp32s3 as mcu;
 
 pub use super::esp32s3::{
@@ -11,6 +12,8 @@ pub use super::esp32s3::{
 
 pub type UsbDriver = esp_hal::otg_fs::asynch::Driver<'static>;
 
+pub type LedDriver = SimpleLed<Output<'static>>;
+
 pub struct UsbParts {
     pub driver: UsbDriver,
 }
@@ -27,6 +30,7 @@ impl LoRaBoard for Board {
     type CommParts = UsbParts;
     type DisplayParts = DisplayParts;
     type DisplayDriver = DisplayDriver;
+    type LedDriver = LedDriver;
 
     fn init() -> Self {
         let p = esp_hal::init(esp_hal::Config::default());
@@ -37,7 +41,7 @@ impl LoRaBoard for Board {
         mcu::mac_address()
     }
 
-    fn into_parts(self) -> BoardParts<RadioParts, UsbParts, DisplayParts> {
+    fn into_parts(self) -> BoardParts<RadioParts, UsbParts, DisplayParts, LedDriver> {
         let p = self.p;
 
         mcu::start_timer(p.TIMG0);
@@ -71,10 +75,15 @@ impl LoRaBoard for Board {
         let i2c = mcu::init_i2c(p.I2C0, p.GPIO17, p.GPIO18);
         let display = Some(DisplayParts { i2c });
 
+        // Orange LED on GPIO35
+        let led_pin = Output::new(p.GPIO35, Level::Low, OutputConfig::default());
+        let led = SimpleLed(led_pin);
+
         BoardParts {
             radio,
             host,
             display,
+            led,
             mac: Self::mac_address(),
         }
     }

firmware/src/board/rak_wisblock_4631.rs

@@ -20,6 +20,7 @@ type RadioSpiDevice = SpiDevice<'static, NoopRawMutex, mcu::SpiBus, Nss>;
 pub type RadioDriver = Sx126x<RadioSpiDevice, Iv, Sx1262>;
 pub type UsbDriver = mcu::UsbNrfDriver;
 pub type DisplayI2c = mcu::I2cBus;
+pub type LedDriver = ();
 
 pub type DisplayDriver = ssd1306::Ssd1306Async<
     ssd1306::prelude::I2CInterface<DisplayI2c>,
@@ -77,6 +78,7 @@ impl LoRaBoard for Board {
     type CommParts = UsbParts;
     type DisplayParts = DisplayParts;
     type DisplayDriver = DisplayDriver;
+    type LedDriver = ();
 
     fn init() -> Self {
         let p = embassy_nrf::init(Default::default());
@@ -87,7 +89,7 @@ impl LoRaBoard for Board {
         mcu::mac_address()
     }
 
-    fn into_parts(self) -> BoardParts<RadioParts, UsbParts, DisplayParts> {
+    fn into_parts(self) -> BoardParts<RadioParts, UsbParts, DisplayParts, ()> {
         let p = self.p;
 
         // ── SPI bus for SX1262 ──────────────────────────────────
@@ -135,6 +137,7 @@ impl LoRaBoard for Board {
             radio,
             host,
             display,
+            led: (),
             mac: Self::mac_address(),
         }
     }

firmware/src/board/traits.rs

@@ -1,14 +1,23 @@
 //! Board abstraction trait.
 //!
 //! Every board must implement [`LoRaBoard`] with concrete associated types
-//! for its radio, host communication, and display peripherals. The compiler
+//! for its radio, host communication, display, and LED peripherals. The
-//! enforces completeness — missing types or methods are compile errors.
+//! compiler enforces completeness — missing types or methods are compile errors.
 //!
 //! See `src/board/PORTING.md` for a step-by-step guide to adding a new board.
 
 use embedded_graphics::draw_target::DrawTarget;
 use embedded_graphics::pixelcolor::BinaryColor;
 
+/// Async RGB LED control. Boards without an LED use `()` which is a no-op.
+pub trait RgbLed {
+    fn set_rgb(&mut self, r: u8, g: u8, b: u8) -> impl core::future::Future<Output = ()>;
+}
+
+impl RgbLed for () {
+    async fn set_rgb(&mut self, _r: u8, _g: u8, _b: u8) {}
+}
+
 /// Compile-time contract for a DongLoRa board.
 pub trait LoRaBoard: Sized {
     /// Human-readable board name (shown on display splash screen).
@@ -29,6 +38,9 @@ pub trait LoRaBoard: Sized {
     /// Concrete display driver type (must implement DrawTarget for rendering).
     type DisplayDriver: DrawTarget<Color = BinaryColor>;
 
+    /// RGB LED driver. Boards without an LED use `()`.
+    type LedDriver: RgbLed;
+
     /// Initialize the board hardware.
     fn init() -> Self;
 
@@ -36,13 +48,14 @@ pub trait LoRaBoard: Sized {
     fn mac_address() -> [u8; 6];
 
     /// Decompose initialized board into peripheral bundles for each task.
-    fn into_parts(self) -> BoardParts<Self::RadioParts, Self::CommParts, Self::DisplayParts>;
+    fn into_parts(self) -> BoardParts<Self::RadioParts, Self::CommParts, Self::DisplayParts, Self::LedDriver>;
 }
 
 /// Peripheral bundles for each firmware task, produced by [`LoRaBoard::into_parts`].
-pub struct BoardParts<R, C, D> {
+pub struct BoardParts<R, C, D, L> {
     pub radio: R,
     pub host: C,
     pub display: Option<D>,
+    pub led: L,
     pub mac: [u8; 6],
 }

firmware/src/board/wio_tracker_l1.rs

@@ -21,6 +21,8 @@ pub type RadioDriver = Sx126x<RadioSpiDevice, Iv, Sx1262>;
 pub type UsbDriver = mcu::UsbNrfDriver;
 pub type DisplayI2c = mcu::I2cBus;
 
+pub type LedDriver = crate::driver::simple_led::SimpleLed<Output<'static>>;
+
 pub type DisplayDriver = crate::driver::sh1106::Sh1106<DisplayI2c>;
 
 // ── Peripheral bundles ──────────────────────────────────────────────
@@ -66,6 +68,7 @@ impl LoRaBoard for Board {
     type CommParts = UsbParts;
     type DisplayParts = DisplayParts;
     type DisplayDriver = DisplayDriver;
+    type LedDriver = LedDriver;
 
     fn init() -> Self {
         let mut config = embassy_nrf::config::Config::default();
@@ -79,7 +82,7 @@ impl LoRaBoard for Board {
         mcu::mac_address()
     }
 
-    fn into_parts(self) -> BoardParts<RadioParts, UsbParts, DisplayParts> {
+    fn into_parts(self) -> BoardParts<RadioParts, UsbParts, DisplayParts, LedDriver> {
         let p = self.p;
 
         // ── SPI bus for SX1262 ──────────────────────────────────
@@ -129,10 +132,15 @@ impl LoRaBoard for Board {
         );
         let display = Some(DisplayParts { i2c });
 
+        // Green LED on P1.01
+        let led_pin = Output::new(p.P1_01, Level::Low, OutputDrive::Standard);
+        let led = crate::driver::simple_led::SimpleLed(led_pin);
+
         BoardParts {
             radio,
             host,
             display,
+            led,
             mac: Self::mac_address(),
         }
     }

firmware/src/display.rs

@@ -6,11 +6,9 @@ use embassy_time::Timer;
 use embedded_graphics::draw_target::DrawTarget;
 use embedded_graphics::pixelcolor::BinaryColor;
 
-use crate::board::DisplayParts;
+use crate::board::{Board, DisplayParts, LedDriver, LoRaBoard, RgbLed};
 use crate::channel::{DisplayCommand, DisplayCommandChannel, RadioState, RadioStatus, StatusWatch};
 
-use crate::board::{Board, LoRaBoard};
-
 use render::RSSI_HISTORY_LEN;
 
 const BOARD_NAME: &str = Board::NAME;
@@ -78,6 +76,14 @@ impl DisplayState {
     }
 }
 
+/// Map SNR (dB) to LED brightness (4..64). Stronger signal = brighter.
+fn snr_brightness(snr: Option<i16>) -> u8 {
+    let snr = snr.unwrap_or(-10);
+    let clamped = snr.clamp(-20, 15) as i32;
+    // -20 → 4, +15 → 64
+    ((clamped + 20) * 60 / 35 + 4) as u8
+}
+
 /// Render the appropriate screen for the current state into the display buffer.
 fn render_current(
     display: &mut impl DrawTarget<Color = BinaryColor>,
@@ -103,6 +109,7 @@ fn render_current(
 #[task]
 pub async fn display_task(
     parts: DisplayParts,
+    mut led: LedDriver,
     status: &'static StatusWatch,
     display_commands: &'static DisplayCommandChannel,
 ) {
@@ -150,19 +157,35 @@ pub async fn display_task(
                 if state.disconnected {
                     continue;
                 }
+                let rx_packet = radio_status.rx_count != state.last_status.rx_count;
+                let tx_packet = radio_status.tx_count != state.last_status.tx_count;
+
                 if let Some(rssi) = radio_status.last_rssi {
-                    if radio_status.rx_count != state.last_status.rx_count {
+                    if rx_packet {
                         state.record_rssi(rssi);
                     }
                 }
-                if radio_status.tx_count != state.last_status.tx_count {
+                if tx_packet {
                     state.record_tx();
                 }
+                let last_snr = radio_status.last_snr;
                 state.last_status = radio_status;
 
                 if state.display_on {
                     render_current(&mut display, &state, &board_info);
                     let _ = display.flush().await;
+
+                    // Brief LED blink: red on TX, green scaled by SNR on RX
+                    if tx_packet {
+                        led.set_rgb(32, 0, 0).await;
+                        Timer::after_millis(50).await;
+                        led.set_rgb(0, 0, 0).await;
+                    } else if rx_packet {
+                        let b = snr_brightness(last_snr);
+                        led.set_rgb(0, b, 0).await;
+                        Timer::after_millis(50).await;
+                        led.set_rgb(0, 0, 0).await;
+                    }
                 }
             }
             Either3::Second(cmd) => match cmd {
@@ -171,6 +194,7 @@ pub async fn display_task(
                     state.display_on = false;
                     render::blank(&mut display);
                     let _ = display.flush().await;
+                    led.set_rgb(0, 0, 0).await;
                 }
                 DisplayCommand::On => {
                     state.disconnected = false;
@@ -185,6 +209,7 @@ pub async fn display_task(
                     state = DisplayState::new();
                     render::splash(&mut display, &board_info);
                     let _ = display.flush().await;
+                    led.set_rgb(0, 0, 0).await;
                 }
             },
             Either3::Third(()) => {

firmware/src/driver/mod.rs

@@ -1,2 +1,5 @@
 #[cfg(feature = "wio_tracker_l1")]
 pub mod sh1106;
+
+#[cfg(any(feature = "heltec_v3", feature = "heltec_v3_uart", feature = "heltec_v4", feature = "wio_tracker_l1"))]
+pub mod simple_led;

firmware/src/driver/simple_led.rs

@@ -0,0 +1,20 @@
+//! Simple single-color LED driver (GPIO on/off).
+//!
+//! Generic over any `OutputPin`. Any non-zero RGB value turns the LED on;
+//! all zeros turns it off.
+
+use embedded_hal::digital::OutputPin;
+
+use crate::board::RgbLed;
+
+pub struct SimpleLed<P>(pub P);
+
+impl<P: OutputPin> RgbLed for SimpleLed<P> {
+    async fn set_rgb(&mut self, r: u8, g: u8, b: u8) {
+        if r > 0 || g > 0 || b > 0 {
+            let _ = self.0.set_high();
+        } else {
+            let _ = self.0.set_low();
+        }
+    }
+}

firmware/src/main.rs

@@ -96,7 +96,7 @@ async fn run(spawner: Spawner) {
 
     if let Some(dp) = parts.display {
         spawner
-            .spawn(display::display_task(dp, &STATUS, &DISPLAY_COMMANDS))
+            .spawn(display::display_task(dp, parts.led, &STATUS, &DISPLAY_COMMANDS))
             .expect("spawn display_task");
     }
 }