spectrachrome · spectrachrome · Feb 22, 2026 · Feb 19, 2026 · Feb 20, 2026 · Feb 21, 2026
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -7,6 +7,33 @@ and this project adheres to [Conventional Commits](https://www.conventionalcommi
 
 ## [Unreleased]
 
+### Changed
+
+- Remap AUX strobe switches: AUX7 3-way off → red/green → white, AUX8 momentary → white strobe at 80
+- Add `strobe_split` field to `LedState` for position-light strobe mode
+
+### Added
+
+- Temporal dithering module (`src/dither.rs`): adds extra perceived bit depth to WS2812B LEDs by varying quantized output frame-to-frame faster than flicker fusion
+- `DitherMode` enum with four modes: `Off`, `ErrorDiffusion` (smooth gradients), `Ordered` (Bayer 4x4, deterministic), `Hybrid` (error diffusion + correlated ordered for low brightness)
+- 8.8 fixed-point gamma LUTs (3 x 256 entries, 1536 bytes flash) computed at compile time for high-precision gamma correction in the dithered path
+- `SetDitherMode` and `SetDitherFps` BLE commands for runtime control of dithering
+- `dither_mode` and `dither_fps` fields in BLE `StateResponse`
+- Inner dither loop in LED task: animation renders at `fps` rate, strip refreshes at `dither_fps` rate (100–960 Hz) with different dither patterns between animation frames
+- Dither state auto-reset on mode change, strobe activation, and BLE flash sequences
+- Unit tests for dither algorithms (error diffusion convergence, ordered determinism, Fix16 gamma roundtrip)
+- `DisplayTestPattern` BLE command: temporarily force a color + animation combo for a given duration, overriding FC flight mode patterns
+- `CancelTestPattern` BLE command: stop a running test pattern immediately
+- `test_active` field in BLE `StateResponse` (true when a test pattern is playing)
+- RSSI-based TX link detection via MSP_ANALOG — strobe only activates when RSSI > 0 (replaces unreliable stick-center heuristic)
+- `tx_linked` field exposed in BLE `StateResponse` for app display
+
+### Removed
+
+- Wi-Fi AP hotspot, HTTP web UI, and DHCP server (BLE is now the sole control interface)
+- `embassy-net`, `smoltcp`, `edge-dhcp`, and `embedded-io` dependencies
+- `wifi` and `coex` features from `esp-radio` (no longer needed without Wi-Fi)
+
 ### Added
 
 - BLE Nordic UART Service (NUS) for app control via JSON protocol

diff --git a/Cargo.lock b/Cargo.lock
diff --git a/Cargo.toml b/Cargo.toml
@@ -9,13 +9,6 @@ path = "./src/bin/main.rs"
 
 [dependencies]
 defmt = "0.3.10"
-embassy-net = { version = "0.8.0", features = [
-  "dhcpv4",
-  "medium-ethernet",
-  "tcp",
-  "udp",
-] }
-embedded-io = "0.7.1"
 embedded-io-async = "0.7.0"
 esp-alloc = "0.9.0"
 esp-hal = { version = "1.0.0", features = [
@@ -25,18 +18,6 @@ esp-hal = { version = "1.0.0", features = [
 ] }
 panic-rtt-target = { version = "0.2.0", features = ["defmt"] }
 rtt-target = { version = "0.6.1", features = ["defmt"] }
-smoltcp = { version = "0.12.0", default-features = false, features = [
-  "medium-ethernet",
-  "multicast",
-  "proto-dhcpv4",
-  "proto-dns",
-  "proto-ipv4",
-  "socket-dns",
-  "socket-icmp",
-  "socket-raw",
-  "socket-tcp",
-  "socket-udp",
-] }
 bleps = { git = "https://github.com/bjoernQ/bleps", package = "bleps", rev = "a5148d8ae679e021b78f53fd33afb8bb35d0b62e", features = [
   "async",
   "macros",
@@ -56,10 +37,8 @@ esp-rtos = { version = "0.2.0", features = [
 ] }
 esp-radio = { version = "0.17.0", features = [
   "ble",
-  "coex",
   "defmt",
   "esp32c3",
-  "wifi",
   "unstable",
 ] }
 heapless = { version = "0.8.0", default-features = false, features = ["serde"] }
@@ -70,7 +49,7 @@ static_cell = { version = "2.1.0", features = ["nightly"] }
 smart-leds = "0.4.0"
 ws2812-spi = "0.5.1"
 esp-bootloader-esp-idf = { version = "0.4.0", features = ["esp32c3"] }
-edge-dhcp = { version = "0.7.0", features = ["io", "defmt"] }
+
 
 [profile.dev]
 # Rust debug is too slow.

diff --git a/FLUTTER_BLE_GUIDE.md b/FLUTTER_BLE_GUIDE.md
@@ -4,7 +4,7 @@ This guide is for building a Flutter companion app that controls the AirLED ESP3
 
 ## Architecture Overview
 
-The device runs on an ESP32-C3 (XIAO form factor) and exposes a **Nordic UART Service (NUS)** over BLE. Communication is newline-delimited JSON over a serial-like BLE pipe. The device also runs a Wi-Fi AP with HTTP control as a fallback, but BLE is the primary interface for the app.
+The device runs on an ESP32-C3 (XIAO form factor) and exposes a **Nordic UART Service (NUS)** over BLE. Communication is newline-delimited JSON over a serial-like BLE pipe. BLE is the primary and only control interface for the app.
 
 ## BLE Connection
 
@@ -219,6 +219,32 @@ Per-frame amplitude decay percentage. Only applies in ripple mode.
 
 - `value`: `u8` (clamped 90–99), default **97**
 
+### DisplayTestPattern
+
+Temporarily force a color + animation combo for a given duration, overriding FC flight mode patterns.
+
+```json
+{"DisplayTestPattern":{"color":"rainbow","anim":"ripple","duration_ms":5000}}
+```
+
+- `color`: string — any valid color mode key (see SetColorMode)
+- `anim`: string — any valid animation mode key (see SetAnimMode)
+- `duration_ms`: `u16` (1–65535) — how long to display the test pattern in milliseconds
+
+Returns `ok\n` on success, or `err:unknown_color_mode\n` / `err:unknown_anim_mode\n` on invalid values.
+
+The test pattern overrides FC flight mode displays but not AUX strobe or BLE flash indicators. When the duration expires, the device reverts to normal behavior and pushes a state update.
+
+### CancelTestPattern
+
+Stop a running test pattern immediately and revert to normal behavior.
+
+```json
+{"CancelTestPattern":null}
+```
+
+Returns `ok\n`. Safe to send even when no test pattern is active.
+
 ## StateResponse (device → app)
 
 Full JSON state snapshot. Approximately 250 bytes serialized.
@@ -242,7 +268,9 @@ Full JSON state snapshot. Approximately 250 bytes serialized.
   "ripple_width": 190,
   "ripple_decay": 97,
   "fc_connected": false,
-  "flight_mode": "arming_forbidden"
+  "flight_mode": "arming_forbidden",
+  "tx_linked": false,
+  "test_active": false
 }
 ```
 
@@ -268,6 +296,8 @@ Full JSON state snapshot. Approximately 250 bytes serialized.
 | `ripple_decay` | int | 90–99 | Ripple decay % |
 | `fc_connected` | bool | | Flight controller connected |
 | `flight_mode` | string | see below | Current flight mode |
+| `tx_linked` | bool | | RC transmitter link active (RSSI > 0) |
+| `test_active` | bool | | A BLE test pattern is currently playing |
 
 ### Flight modes