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managed_components/espressif__knob/examples/usb_surface_dial/README.md

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+## USB HID Surface Dial
+
+This example shows how to use the ESP32-Sx USB function to emulate a Windows knob that allows volume control, page up and down, and more.
+
+## Hardware Required
+
+![surface_dial_physical](_static/surface_dial_physical.jpg)
+
+- Any ESP32-Sx development board with **knob** functionality. 
+    - The knob can be a series of rotary encoders with push function such as EC11
+    - It is also possible to use three buttons that simulate: press, left turn, right turn
+
+- Hardware Connection： 
+    - GPIO19 to USB_D-
+    - GPIO20 to USB_D+
+    - GPIO42 to EC11_E
+    - GPIO1  to EC11_A
+    - GPIO2  to EC11_C
+
+![schematic](_static/schematic.png)
+
+![schematic](_static/package.png)
+
+## Build and Flash
+
+1. Set up the `ESP-IDF` environment variables，you can refer [Set up the environment variables](https://docs.espressif.com/projects/esp-idf/en/latest/esp32/get-started/index.html#step-4-set-up-the-environment-variables), Linux can using:
+
+    ```
+    . $HOME/esp/esp-idf/export.sh
+    ```
+
+2. Set ESP-IDF build target to `esp32s2` or `esp32s3`
+
+    ```bash
+    idf.py set-target esp32s2
+    ```
+
+3. Build, Flash, output log
+
+    ```bash
+    idf.py build flash monitor
+    ```
+
+## How To Use
+
+* Connect the USB to the Windows USB port and wait for the USB device to finish installing
+* Press and hold the button to wake up the Windows wheel
+
+![Surface dial](_static/surface_dial.png)