Improvements to "Reset the Arduino bootloader on the Nano ESP32" [HC-1612]

content/Hardware Support/Nano Family/Reset-the-Arduino-bootloader-on-the-Nano-ESP32.md

@@ -3,36 +3,65 @@ title: Reset the Arduino bootloader on the Nano ESP32
 id: 9810414060188
 ---
 
-Learn how to reset the default Arduino bootloader on the Nano ESP32 using Arduino IDE.
+Learn how to reset the default Arduino bootloader on the Nano ESP32.
 
 These are some reasons you may want to reset the bootloader:
 
 * Update the Arduino bootloader already on the board. This can resolve issues with Nano ESP32 being misidentified as other ESP32 boards.
 * Restore the ability to upload regular Arduino sketches to a Nano ESP32 that has been flashed with the MicroPython firmware.
 
+In this article:
+
+* [Option 1: Using the bootloader mode](#bootloader-mode)
+* [Option 2: Use the Esptool programmer option in Arduino IDE](#esp32-download-mode)
+
+---
+
+## Option 1: Using bootloader mode {#bootloader-mode}
+
+The quickest way to reset your Arduino Nano ESP32 is by activating the bootloader mode and uploading any sketch.
+
+Follow these steps:
+
+1. Press the RST button two times, waiting 0.3 to 1 second between each press.
+
+   > [!IMPORTANT]
+   > The timing between presses is different compared to bootloader mode on most other Arduino boards. If bootloader mode won’t activate, try adjusting your timing.
+
+2. Check the on-board LED near the RST button:
+   * **If the LED pulses slowly in green[^colors]:** The board is in bootloader mode. Go to the next step.
+   * **If the LED is off:** Repeat step 1 or try [Option 2: Use the Esptool programmer option in Arduino IDE](#esp32-download-mode).
+3. Select Arduino Nano ESP32 in Arduino IDE or the Cloud Editor.
+4. Upload any sketch to restore the standard Arduino bootloader.
+
 ---
 
-Before you begin, it is recommended to have the latest version of the **Arduino ESP32 Boards** or **esp32** boards package installed using the Board Manager.
+## Option 2: Use the Esptool programmer option in Arduino IDE {#esp32-download-mode}
+
+> [!TIP]
+> Before you begin, it is recommended to have the latest version of the **Arduino ESP32 Boards** or **esp32** boards package installed using the Board Manager.
 
 Follow these steps:
 
-1. Connect a jumper cable between the **GND** and **B1** pins. The RGB LED will turn on with a green or blue color.
+1. Connect a jumper cable between the **GND** and **B1** pins. The RGB LED will turn on with a green[^colors] color.
 
    ![The GND and B1 pins](img/nano-esp32-gnd-b1.png)
 
 2. While the **GND** and **B1** pins are shorted, press the white **RST** button on the top of the board to reset the board to **firmware download mode**.
 
-3. Remove the jumper cable. The RGB LED should stay on, in a purple or yellow color.
+3. Remove the jumper cable. The RGB LED should stay on, in a purple[^colors] color.
 
 4. Open Arduino IDE.
 
 5. Go to **Tools > Port** and select the board (it may be identified as an arbitrary ESP32 board).
 
 6. Go to **Tools > Board** and select **Arduino ESP32 Boards > Arduino Nano ESP32** (or **esp32 > Arduino Nano ESP32** if you're using the full esp32 package).
 
-7. Open **Tools > Programmer** and ensure **Esptool** is selected.
+7. Open the **Tools > Programmer** menu.
+
+8. Click on the **Esptool** option to select it.
 
-8. Select **Sketch > Upload Using Programmer** to begin uploading the firmware.
+9. Select **Sketch > Upload Using Programmer** to begin uploading the firmware.
 
    The process is complete when you see these lines:
 
@@ -41,4 +70,22 @@ Follow these steps:
    Hard resetting via RTS pin...
    ```
 
-9. Press the **RST** button on top of the board to exit firmware download mode.
+10. Press the **RST** button on top of the board to exit firmware download mode.
+
+### Troubleshooting
+
+#### dfu-util: No DFU capable USB device available
+
+If you see this error, it means that the sketch is still being uploading with the regular upload process.
+
+Try this:
+
+* Ensure that the **Esptool** option is selected in the **Sketch > Upload Using Programmer** menu. It needs to be actively selected, even if no other options are available. You will know the Esptool option is selected if a checkmark is displayed next to the name.
+
+  ![The Esptool option in the Tools > Programmer menu. A checkmark indicates that the option is currently selected.](img/esptool-selected.png)
+
+* Ensure you are uploading the sketch by selecting **Sketch > Upload Using Programmer** and not by clicking the regular Upload button.
+
+[^colors]: On some earlier versions of the Nano ESP32, the LED will be blue instead of green, and yellow instead of purple.
+
+<!-- markdownlint-disable-file HC001 -->