documentation #586: document bluetooth

Author: FabienDanieau

docs/assets/bluetooth_1.jpg

@@ -0,0 +1,53 @@
+
+# ReachyMini nRF Connect Guide
+
+Reachy Mini wireless emits a Bluetooth signal that allows you to reset the Wi-Fi hotspot or the daemon.
+
+## 1. Install nRF Connect
+- **Android**: [Download here](https://play.google.com/store/apps/details?id=no.nordicsemi.android.mcp&hl=en-US&pli=1)
+- **iOS**: [Download here](https://apps.apple.com/us/app/nrf-connect-for-mobile/id1054362403)
+
+
+## 2. Scan and Connect
+1. Open nRF Connect.
+2. Scan for devices and select **ReachyMini**.
+[![bluetooth_1.jpg](/docs/assets/bluetooth_1.jpg)]()
+3. Connect to the device.
+
+
+
+## 3. Unknown Service & WRITE Section
+- Navigate to the **Unknown Service**.
+- Locate the **WRITE** section.
+[![bluetooth_2.jpg](/docs/assets/bluetooth_2.jpg)]()
+
+
+
+## 4. Sending Commands
+Commands are sent as **hexadecimal strings**. Use [this tool](https://www.rapidtables.com/convert/number/ascii-to-hex.html) to convert ASCII to hex if needed.
+
+
+### Available Commands
+| Command                | Hex Value (send after `0x`)       |
+|------------------------|-----------------------------------|
+| STATUS                 | 535441545553                      |
+| PIN_00018              | 50494E5F3030303138                |
+| CMD_HOTSPOT            | 434D445F484F5453504F54            |
+| CMD_RESTART_DAEMON     | 434D445F524553544152545F4441454D4F4E |
+| CMD_SOFTWARE_RESET     | 434D445F534F4654574152455F5245534554 |
+
+
+### PIN Code
+
+The PIN code here is 00018, for example. The PIN is the **last 5 digits** of the robot's serial number.
+
+
+### Tips
+
+It is good practice to save the commands for later use.
+[![bluetooth_3.jpg](/docs/assets/bluetooth_3.jpg)]()
+[![bluetooth_4.jpg](/docs/assets/bluetooth_4.jpg)]()
+
+
+
+

docs/assets/bluetooth_2.jpg

@@ -218,8 +218,15 @@ It’s fixed! You can now enjoy all the features of Reachy Mini again. Head over
 5. Enter your Wi-Fi network credentials (SSID and password) and click "Connect".
 6. Wait a few moments for Reachy Mini to connect to your Wi-Fi network. The access point will disappear once connected. If the connection fails, Reachy Mini will restart the access point, and you can try again.
 
-</details><br>
+</details> <br>
+
+<details>
+<summary><strong>How do I reset the Wi-Fi hotspot?</strong>
+<br>Tags: <kbd>WiFi</kbd> <kbd>TROUBLESHOOTING</kbd> <kbd>WIRELESS</kbd></summary>
+
+If you need to reset the robot's Wi-Fi hotspot (for example, if you can't connect or want to change the network), follow the instructions in the [Wi-Fi Reset Guide](/docs/platforms/reachy_mini/reset.md).
 
+</details> <br>
 
 <details>
 <summary>