.. _lwip_tcpecho_multi_ports_rtthread_nano:

lwip_tcpecho_multi_ports_rtthread-nano
============================================================================

Overview
--------

This example shows TCP echo communication on multiple ports on RTThread-Nano.

- PC sends TCP data frames to MCU,  and then MCU sends the data frames back to PC

Board Settings
--------------

- Connect a USB port on PC to the PWR DEBUG port on the development board with a USB Type-C cable

- Connect two Ethernet ports on PC to a RGMII port and a RMII port on the development board with two Ethernet cables

Project Configurations
----------------------

- Ethernet Port Settings: Refer to :ref:`Ethernet common project settings <ethernet_port_configurations_en>`

- Ethernet DHCP Configurations

  - the configurations in the `CMakeLists.txt` as follows:

    - sdk_compile_definitions(-DLWIP_DHCP=0): Disable DHCP feature

    - sdk_compile_definitions(-DLWIP_DHCP=1): Enable DHCP feature

Run Example
-----------

- Compiling and Downloading

- Running log is shown in the serial terminal as follows:


  .. code-block:: 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


- Run an Ethernet debugging tool

  - create and set two TCP clients:

    TCP Server 0 IP: 192.168.100.10/Port: 5001
    TCP Server 1 IP: 192.168.200.10/Port: 5002

    **Note: There is a necessary adjustment for Server IP according to the segment of  LAN where PC resides**

  - Connect

  - Enter and send any characters in the edit window(192.168.100.10/5001)

    .. image:: ../../../../../samples/lwip/doc/lwip_tcpecho_multi_ports_0_1.png

  - Watch the characters echoed from MCU window(192.168.100.10/5001)

    .. image:: ../../../../../samples/lwip/doc/lwip_tcpecho_multi_ports_0_2.png

  - Enter and send any characters in the edit window(192.168.200.10/5002)

    .. image:: ../../../../../samples/lwip/doc/lwip_tcpecho_multi_ports_1_1.png

  - Watch the characters echoed from MCU window(192.168.200.10/5002)

    .. image:: ../../../../../samples/lwip/doc/lwip_tcpecho_multi_ports_1_2.png