1、功能说明
    USB MSC + CDC 组合设备

2、使用环境

    软件开发环境：KEIL MDK-ARM 5.34
                  IAR EWARM 8.50.1

    硬件开发环境：
        N32H482系列：
        基于评估板N32H482ZEL7_STB V1.0开发
        N32H487系列：
        基于评估板N32H487ZEL7_STB V1.1开发


3、使用说明
    描述相关模块配置方法；例如:时钟，I/O等 
         1. SystemClock：240MHz
		 2. USBClock: HSE 16MHz
         3. 串口：USART1 TX -- PA9  RX -- PA10 波特率：115200
         4. SPI1配置：NSS--PA4、SCK--PA5、MISO--PA6、MOSI--PA7 (连接W25Q128)


    描述Demo的测试步骤和现象 
         1. 编译后下载程序复位运行；
         2. 通过 USB 线连接 J62 USB 口，电脑识别出虚拟串口设备和U 盘设备
         3. 将 USART1 接到串口工具上，然后在PC上打开 USB 虚拟串口，USB 虚拟串口发送数据，
            用串口工具接收数据，然后用串口工具发送数据， USB 虚拟串口接收数据


4、注意事项
    首次挂载 U 盘需要格式化，格式化完成后即可当成 U 盘使用。在N32H487ZEL7_EVB V1.1开发板上，J29和J31用跳线帽连接；
    可通过修改宏定义 USE_USB_HS_IN_FS 或 USE_USB_HS_IN_HS 切换设备为全速模式或者高速模式；
    另外需要使用16MHz、19.2MHz、20MHz、24MHz、26MHz或32MHz外部晶体。

1. Function description
    USB MSC + CDC composite device

2. Use environment
    Software development environment: KEIL MDK-ARM V5.34
                                      IAR EWARM 8.50.1

    Hardware development environment:
        N32H482 series:
        Developed based on the evaluation board N32H482ZEL7_STB V1.0
        N32H487 series:
        Developed based on the evaluation board N32H487ZEL7_STB V1.1

3. Instructions for use
    Describe the configuration method of related modules; for example: clock, I/O, etc. 
        1. SystemClock: 240MHz
		2. USBClock: HSE 16MHz
        3. Serial port: USART1 TX -- PA9 RX -- PA10 Baud rate: 115200
        4. SPI1 configuration: NSS--PA4, SCK--PA5, MISO--PA6, MOSI--PA7 (connected to W25Q128)

    Describe the testing steps and phenomena of the Demo
    1. After compiling, the downloaded program is reset and run;
    2. Connect a USB cable to the J62 USB port. The computer identifies the virtual serial port device and U disk device
    3. Connect USART1 to the serial port tool, then open the USB virtual serial port on the PC, and send data through the USB virtual serial port.
       Use the serial port tool to receive data, and then use the serial port tool to send data, USB virtual serial port to receive data
    
        
4. Attention
     The first mount U disk needs to be formatted, and it can be used as a U disk after formatting. On N32H487ZEL7_EVB V1.1 board, J29 and J31 Connected with jumper cap;
     The device can be switched to Full-Speed mode or High-Speed mode by modify the macro definition USE_USB_HS_IN_FS or USE_USB_HS_IN_HS;
     In addition, external crystal of 16MHz, 19.2MHz, 20MHz, 24MHz, 26MHz or 32MHz is required.