Update README

README.md

@@ -19,11 +19,11 @@ A reusable ESP32 firmware base with Wi-Fi, web configuration UI, authentication,
 
 - **Wi-Fi** via WiFiManager — captive-portal setup on first boot, credentials stored in flash
 - **mDNS** — device reachable as `<hostname>.local`
-- **Web UI** — responsive configuration page served from the device
+- **Web UI** — responsive configuration page served from the device, with logo support
 - **Authentication** — optional HTTP Basic Auth to protect the web UI
 - **MQTT** — connects to any broker, publishes an availability topic, reconnects automatically without blocking the web server
 - **Home Assistant discovery** — stub ready for your entities
-- **Factory reset** — rapid 5× power-cycle clears all settings and restarts
+- **Factory reset** — rapid power-cycling clears settings (5× config, 10× config + Wi-Fi credentials)
 - **Config persistence** — all settings stored as JSON in LittleFS (`/config.json`)
 
 ---
@@ -34,16 +34,21 @@ The project uses [PlatformIO](https://platformio.org/).
 
 ```bash
 # Build
-pio run
+pio run -e esp32dev
 
-# Flash
+# Flash firmware
-pio run --target upload
+pio run -e esp32dev --target upload
 
-# Open serial monitor (115200 baud)
+# Upload filesystem image (logo, etc.) — only needed when data/ changes
+pio run -e esp32dev --target uploadfs
+
+# Open serial monitor (115 200 baud)
 pio device monitor
 ```
 
-Board target: `esp32-s3-devkitc-1`
+> **Note:** close the serial monitor before uploading — it holds the serial port exclusively.
+
+Board targets: `esp32dev`, `esp32-s3-devkitc-1`
 
 ---
 
@@ -52,7 +57,7 @@ Board target: `esp32-s3-devkitc-1`
 On first boot (or when stored Wi-Fi credentials are missing), the device starts an access point named **ESP32-Device**. Connect to it with any phone or laptop — a captive portal will appear automatically.
 
 1. Enter your Wi-Fi SSID and password.
-2. Optionally change the **Device hostname** (default: `esp32-device`).
+2. Optionally change the **Device hostname** (default: `esp32-device`, max 63 characters).
 3. Click **Save**. The device connects to your network and restarts.
 
 After connecting, the device is reachable at:
@@ -62,16 +67,21 @@ After connecting, the device is reachable at:
 
 ### Factory reset
 
-If you lose the web UI password or need to clear all settings, **reset the device 5 times in quick succession** (press EN or cycle power 5× within a few seconds, before boot completes). All settings are wiped and the device restarts into the Wi-Fi captive portal.
+Power-cycle (or press EN) rapidly before the 3-second boot window expires. The reset counter accumulates across rapid reboots:
 
-Serial output shows the progress:
+| Cycles | Effect |
+|--------|--------|
+| 5 – 9  | Clears hostname, auth, and MQTT config; restarts into normal Wi-Fi |
+| 10+    | Clears all of the above **plus** stored Wi-Fi credentials; restarts into captive portal |
+
+Serial output shows the accumulated count:
 
 ```
-[BOOT] reset count 1/5
+[BOOT] reset count 3
-[BOOT] reset count 2/5
+[BOOT] reset count 4
 ...
-[BOOT] reset count 5/5, triggering factory reset
+[BOOT] reset count 5, triggering factory reset
-[BOOT] factory reset triggered!
+[BOOT] factory reset triggered (clearWifi=0)!
 [BOOT] factory reset complete, restarting...
 ```
 
@@ -81,13 +91,17 @@ Serial output shows the progress:
 
 Browse to the device address to open the configuration page.
 
+### Logo
+
+Place a `logo.png` in the `data/` directory and upload the filesystem image once. The logo appears in the top-left of the configuration page. The `data/logo.png` included in this repo is a 200×200 px transparent PNG.
+
 ### Info panel
 
 Shows the current hostname and IP address.
 
 ### Hostname
 
-Sets the mDNS name (`<hostname>.local`) and the MQTT client ID. Saved across reboots.
+Sets the mDNS name (`<hostname>.local`). Changing the hostname automatically restarts the device so mDNS re-registers with the new name.
 
 ### Security
 
@@ -106,7 +120,7 @@ Sets the mDNS name (`<hostname>.local`) and the MQTT client ID. Saved across reb
 | User / Pass | Broker credentials (leave Pass blank to keep the existing value) |
 | Prefix | Topic prefix (default `device`) |
 
-Click **Save** to persist all settings.
+Click **Save** to persist all settings. Click **Reset Device** to restart the device immediately.
 
 ---
 
@@ -130,13 +144,12 @@ Three stubs in `main.cpp` are the intended extension points:
 
 ## HTTP API
 
-### `GET /`
+| Method | Path | Description |
-
+|--------|------|-------------|
-Returns the HTML configuration page.
+| `GET` | `/` | HTML configuration page |
-
+| `GET` | `/logo.png` | Logo image served from LittleFS |
-### `POST /config`
+| `POST` | `/config` | Save configuration; redirects to `/`. Restarts if hostname changed |
-
+| `POST` | `/reset` | Restart the device immediately |
-Saves all configuration submitted by the HTML form. Redirects back to `/`.
 
 ---
 
@@ -173,3 +186,4 @@ The file is written by the web UI. To erase everything including flash, use `pio
 3. Fill in the three MQTT stubs to subscribe, receive, and publish discovery payloads.
 4. Add extra web routes with `server.on(...)` in `startServer()` if you need device-specific endpoints.
 5. Persist extra config fields by adding keys to `loadConfig()` and `saveConfig()`.
+6. Place static files (images, etc.) in `data/` and upload the filesystem image with `pio run --target uploadfs`.