# lwip_tcpecho_multi_ports_rtthread-nano
## 概述
本示例展示在RTThread-Nano下多端口TCP回送通讯
- PC 通过以太网发送TCP数据帧至MCU，MCU将接收的数据帧回发至PC
## 硬件设置
* 使用USB Type-C线缆连接PC USB端口和PWR DEBUG端口
* 使用两根以太网线缆连接PC以太网端口和开发板上RGMII端口和RMII端口
## 工程配置
- 以太网端口配置：参考 [以太网通用工程设置](../doc/Ethernet_Common_Project_Settings_zh.md)
- 以太网DHCP配置
- lwIP sample: 在`CMakeLists.txt`中，支持如下配置:
- sdk_compile_definitions(-DLWIP_DHCP=0): 禁用DHCP功能
- sdk_compile_definitions(-DLWIP_DHCP=1): 启用DHCP功能
## 运行示例
* 编译下载程序
* 串口终端显示如下信息：
```console
This is an ethernet demo: TCP Echo With Multi Ports On RTThread-Nano
LwIP Version: 2.1.2
Enet1 Reference Clock: Internal Clock
\ | /
- RT - Thread Operating System
/ | \ 3.1.5 build Mar 18 2024
2006 - 2020 Copyright by rt-thread team
msh >Enet0 init passed!
Enet1 init passed!
================ Network Interface 1 ================
Link Status: Down
================ Network Interface 1 ================
Link Status: Up
Link Speed: 100Mbps
Link Duplex: Full duplex
================ Network Interface 1 ================
IPv4 Address: 192.168.200.10
IPv4 Netmask: 255.255.255.0
IPv4 Gateway: 192.168.200.1
================ Network Interface 0 ================
Link Status: Down
================ Network Interface 0 ================
Link Status: Up
Link Speed: 1000Mbps
Link Duplex: Full duplex
================ Network Interface 0 ================
IPv4 Address: 192.168.100.10
IPv4 Netmask: 255.255.255.0
IPv4 Gateway: 192.168.100.1
```
* 打开以太网调试工具
- 创建并设置TCP客户端：
TCP服务端0 IP: 192.168.100.10/端口: 5001
TCP服务端1 IP: 192.168.200.10/端口: 5002
**注：实际需要根据PC所在局域网段调整服务端IP**
- 连接
- 在数据发送窗口(192.168.100.10/5001)编辑发送字符
- 观察回送数据窗口(192.168.100.10/5001)
- 在数据发送窗口(192.168.200.10/5002)编辑发送字符
- 观察回送数据窗口(192.168.200.10/5002)
