1、功能说明
    本工程为裸机环境下（no OS）的LwIP移植示例，使用ping命令验证移植的正确性。

2、使用环境

    软件开发环境：
        KEIL MDK-ARM V5.34
        IAR EWARM 8.50.1

    硬件开发环境：
        基于全功能板N32H497ZGL7_EVB V1.0开发

3、使用说明
    
    系统配置：
        1、时钟源：HSI+PLL
        2、时钟频率：240MHz
        3、打印：PA9 - baud rate 115200

    以太网配置：
        1、PHY接口：RMII
        2、引脚分配：
            ETH_MDC<----->PC1
            ETH_MDIO<----->PA2
            ETH_RMII_REF_CLK<----->PA1
            ETH_RMII_CRS_DV<----->PA7
            ETH_RMII_RX_D0<----->PC4
            ETH_RMII_RX_D1<----->PC5
            ETH_RMII_TX_EN<----->PG11
            ETH_RMII_TX_D0<----->PG13
            ETH_RMII_TX_D1<----->PG14
            ETH_PPS_OUT<----->PB5

    使用方法：
        1、编译后下载程序运行，串口将打印本地IP地址、子网掩码、网关等信息
        2、在电脑端使用ping命令以及打印信息中的IP地址，测试网络是否畅通，以此验证移植LwIP的正确性

4、注意事项
    1、您使用的PHY芯片可能与demo默认选择的不一样，请在bsp_eth.h中切换或添加其他PHY的定义；请注意PHY_ADDR，PHY地址值必须与硬件设计保持一致
    2、开发板默认静态IP地址为：192.168.0.32，使用静态IP地址时要确保开发板与电脑处于同一网段，且无IP地址冲突


1. Function description
    This project is an example of LwIP porting in a bare-metal environment (no OS), using the ping command to verify the correctness of the port.

2. Use environment

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

    Hardware development environment:
        Developed based on the full-function board N32H497ZGL7_EVB V1.0

3. Instructions for use
    
    System configuration:
        1, clock source: HSI + PLL
        2, clock frequency: 240MHz
        3, print: PA9 - baud rate 115200

    Ethernet configuration:
        1, PHY interface: RMII
        2, Pin assignment:
            ETH_MDC<----->PC1
            ETH_MDIO<----->PA2
            ETH_RMII_REF_CLK<----->PA1
            ETH_RMII_CRS_DV<----->PA7
            ETH_RMII_RX_D0<----->PC4
            ETH_RMII_RX_D1<----->PC5
            ETH_RMII_TX_EN<----->PG11
            ETH_RMII_TX_D0<----->PG13
            ETH_RMII_TX_D1<----->PG14
            ETH_PPS_OUT<----->PB5

    Usage:
        1, Compile and download the program to run, the serial port will print the local IP address, subnet mask, gateway and other information.
        2, Verify the correctness of porting the LwIP by testing that the network is open using the ping command on the computer side and the IP address in the printout.

4. Attention
    1, The PHY chip you are using may differ from the default selection in this demo. Please switch or add definitions for other PHYs in bsp_eth.h. Note that the PHY_ADDR value must match the hardware design.
    2, The default static IP address of the development board is 192.168.0.32. When using a static IP address, make sure that the board is on the same network segment as the computer and that there are no IP address conflicts.

