Both variants are built from a single codebase and share the same feature set. The `dual` in the filename means a single binary supports both BLE and USB serial — there are no separate BLE/USB builds.
### E-ink Display
The e-ink variant targets the Wio Tracker L1 fitted with a 2.13″ GxEPD2 panel (250 × 122 px). All screens have been adapted for the e-ink panel:
- **Adaptive layout** — every screen reflows correctly in both landscape (250 × 122) and portrait (122 × 250) orientations
- **Display rotation** — configurable in Settings › Display; applied immediately and persisted across reboots
- **Scaled navigation dots** — dot indicators on the home screen scale with line height so they remain visible at all orientations
- **Clock seconds suppressed by default** — seconds are hidden to reduce per-second panel refreshes and extend display lifetime; re-enable in Settings › Display
View and send messages using the on-screen keyboard or predefined quick replies. The keyboard supports placeholders that insert live sensor data — `{time}` and `{loc}` are always available; additional placeholders (`{temp}`, `{hum}`, `{pres}`, `{batt}`, `{alt}`, `{lux}`, `{co2}`) appear automatically for sensors that are connected and returning data.
Press Enter on a message to open it in fullscreen. Navigate between messages with left (newer) and right (older). If the message is a reply addressed to someone (`@[nick]`), a **To: nick** bar is shown below the sender name and the body is displayed without the address prefix.
Hold Enter on a message to open a context menu. From the list or fullscreen view, select **Reply** to pre-fill the keyboard or a quick message with `@[nick]` so the recipient is clearly addressed. The reply picker title shows the recipient's name.
```
╔══════════════════════════════╗
║ RE:Alice ║
╠══════════════════════════════╣
║> Custom message... ║
║ OK, I understand ║
║ On my way ║
║ Be right there ║
╚══════════════════════════════╝
```
On channel or contact list entries, the context menu also lets you change per-channel notification settings (mute, follow global, or force-on), per-channel melody override (follow global, Melody 1, or Melody 2), or mark messages as read.
- Joystick rotation *(e-ink only)* — rotates the joystick input mapping independently of the display rotation; useful when mounting the device in a custom enclosure
- **Home Pages** — toggle visibility and reorder individual home screen pages; press LEFT / RIGHT on any entry to move it earlier or later in the navigation sequence; press ENTER to toggle ON / OFF (Settings and Messages are always visible and cannot be disabled)
A dedicated clock page on the home screen shows the current time and date, synchronized from GPS or via Bluetooth. Timezone offset is applied from Settings.
Up to three configurable data fields are displayed below the clock. Available fields: battery voltage, temperature, humidity, pressure, GPS coordinates, altitude, luminosity, CO₂, contact count, and total unread message count.
Browse nodes that have recently advertised on the mesh. Filter by category (Favourites, All, Companion, Repeater, Room, Sensor). Select a node to see its coordinates, distance, bearing with cardinal direction, type, and last-heard time.
Press **Enter** from the Nearby screen to send a live `NODE_DISCOVER_REQ` ping. All reachable repeaters, sensors and room servers within zero-hop range respond immediately with their name, type and signal data. Results appear as 2-line boxed cards with RSSI, SNR and the remote SNR (signal quality at the responder's end).
```
╔═══════════════════════════════╗
║▓▓▓▓▓▓▓ DISCOVER (2 found) ▓▓ ║
╠═══════════════════════════════╣
║▓▓▓▓▓▓▓▓▓▓▓▓▓ Rptr-A Rpt ▓▓▓▓║ ← selected
║▓▓▓▓▓▓▓▓ RSSI:-79 SNR:9 ▓▓▓▓▓▓▓║
║┌────────────────────────────┐ ║
║│▓▓▓▓▓▓▓▓▓▓▓▓ Sensor-B Snsr │ ║
║│ RSSI:-94 SNR:3 │ ║
║└────────────────────────────┘ ║
╚═══════════════════════════════╝
```
Navigate with **UP/DOWN**. Press **Enter** on a node to open a full-screen detail view showing the public key, RSSI, SNR, remote SNR and whether the node is already in your contacts.
```
╔══════════════════════════════╗
║▓▓▓▓▓▓▓▓▓▓▓▓▓ Rptr-A ▓▓▓▓▓▓▓ ║
╠══════════════════════════════╣
║ Key: ABCdef12XYZ... ║
║ RSSI: -79 dBm ║
║ SNR: 9 dB ║
║ Rem: 6 dB ║
║ Status: known ║
╚══════════════════════════════╝
```
Hold **Enter** from the discovery list to rescan. Press **Cancel** or **Back** to return.
Periodically broadcasts a 0-hop advert with your GPS position so nearby nodes can track your location automatically. Configurable interval: off / 1 min / 2 min / 5 min / 10 min / 30 min / 1 h.
A blinking **A** indicator appears in the status bar while Auto-Advert is active.
A step sequencer for composing custom notification melodies stored on the device. Two independent melody slots are available — **Melody 1** and **Melody 2** — switchable from within the editor. Each melody supports up to 32 notes with adjustable pitch (C–B + pause), octave (4–7), duration (whole / half / quarter / eighth), and BPM (60 / 90 / 120 / 150 / 180). Playback preview is available directly from the editor.
Melodies can be assigned as notification sounds per message type (DM / channel) in Settings, and individually overridden per channel or per contact from the message screen context menu.
Both the default font and the [Lemon bitmap font](https://github.com/cmvnd/fonts) are built into every firmware variant. Switch between them at runtime in **Settings → Display → Font** — no reflashing required. The selected font is saved to flash and takes effect immediately.
This fork tracks the upstream [MeshCore](https://github.com/ripplebiz/MeshCore) repository. To prevent upstream changes from overwriting this README during merges, `README.md` is protected via `.gitattributes`. After cloning, run once:
