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+# RT-Thread package Userguide with usb stack
+
+[中文版](rt-thread_zh.md)
+
+To use usb stack package, you need to select it in the RT-Thread package manager. The specific path is as follows:
+
+```
+-> RT-Thread online packages
+    -> system packages
+        --- USB Stack: tiny and portable USB stack for embedded system with USB IP
+
+            USB STACK Options  ---->
+                    [ ] Enable usb high speed mode
+                    [*] Enable usb device mode
+                    [*]   Enable usb cdc acm device
+                    [ ]   Enable usb hid device
+                    [ ]   Enable usb dfu device
+                    [ ]   Enable usb msc device
+                    [ ]   Enable usb hub device
+                    [ ]   Enable usb audio device
+                    [ ]   Enable usb video device
+
+            Version (latest)  --->
+```
+
+## How to use
+
+### In STM32
+
+Please note that stm32 series have two usb ip. For usb ip, like stm32f0、stm32f1、stm32f3, for usb otg ip(as we know it is from **DesignWare**),like stm32f4、stm32f7 and so on.
+Currently,if you usb usb device on mcu with usb ip, recommend you to use dcd porting named **usb_dc_nohal.c**,otherwise use **usb_dc_hal.c**.In the future,**usb_dc_hal.c** will be droped.
+
+#### Use USB Device
+
+- Firstly,you should have a bsp project,and then go to `board\CubeMX_Config` directory, open file that suffix name with `.ioc` in **STM32CubeMX**.
+- Enable **USB** or **USB_OTG_FS** or **USB_OTG_HS** in **Connectivity** List,enable USB IRQ in **NVIC Setting**.
+
+![STM32CubeMX USB setting](img/stm32cubemx.png)
+
+- Enable USB Clock for 48Mhz in **Clock configuration**.
+
+![STM32CubeMX USB clock](img/stm32cubemx_clk.png)
+
+- Generate code.
+- Copy **SystemClock_Config** into **board.c**.
+- Copy **MX_USB_OTG_FS_PCD_Init** or **MX_USB_OTG_HS_PCD_Init** into **main.c** if you use **usb_dc_hal.c**.Also, USB Irq from **it.c** needs the same.
+- Implement **printf** or modify with **rt_kprintf** in **usb_utils.h**, usb stack needs.
+- Now we can call some functions provided by **usb_stack**.Your should register descriptors、interfaces and endpoint callback firstly, and then call `usb_dc_init`. Example is as follows:
+
+```
+int main(void)
+{
+    extern void cdc_init(void);
+    cdc_init();
+    extern void usb_dc_init(void);
+    usb_dc_init();
+    while (1)
+    {
+        rt_thread_mdelay(500);
+    }
+}
+```
+
+- How to register class you can go to [stm32 class examples](https://github.com/sakumisu/usb_stack/tree/master/demo/stm32/stm32f103c8t6/example) for a reference.
+
+#### CDC Demo Demonstration
+
+![CDC Demo](img/rtt_cdc_demo.png)
+
+#### Video manual
+
+If you have problem from steps above, you can see this video：[Use USB Stack in RT-Thread package manager](https://www.bilibili.com/video/BV1Ef4y1t73d?p=26)。
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