20.7. lwip_ping_freertos_socket

20.7.1. Overview

This example shows the usage of ping on FreeRTOS.

MCU pings the specified network device( Enter IP or URL)

20.7.2. Board Settings

Connect a USB port on PC to the PWR DEBUG port on the development board with a USB Type-C cable
Connect an Ethernet port on PC to a RGMII port or a RMII port on the development board with an Ethernet cable

20.7.3. Project Configurations

Ethernet Port Settings: Refer to Ethernet common project settings
Ethernet DHCP Configurations
- In CMakeLists.txt, if CMake variable LWIP_DHCP is not defined, it defaults to 0 (static IP). The build passes -DLWIP_DHCP=${LWIP_DHCP}.
  - Default (static IP): configure IP0_CONFIG / NETMASK0_CONFIG / GW0_CONFIG in netinfo.h (or override via compile definitions). DNS defaults to 114.114.114.114 when not using DHCP.
  - Enable DHCP: pass -DLWIP_DHCP=1 when configuring CMake (e.g. cmake -DLWIP_DHCP=1 ...), or set LWIP_DHCP to 1 in CMakeLists.txt before the if(NOT DEFINED LWIP_DHCP) block.
- DNS (static IP mode, applies to default build):
  - Default DNS is 114.114.114.114. If the MCU can resolve domestic names but not international ones while the PC works, DNS may differ. Before #if !LWIP_DHCP in lwipopts_app.h, add #define DNS_SERVER_CONFIG 192.168.100.1 (or your gateway IP) to align with the PC.

20.7.4. Run Example

Compiling and Downloading

Running log with the default build (static IP, LWIP_DHCP=0) is shown in the serial terminal as follows. If you build with DHCP enabled (-DLWIP_DHCP=1), lines such as DHCP State: ... appear before the IPv4 lines; addresses follow your network.

This is an ethernet demo: Ping With Socket API On FreeRTOS
LwIP Version: 2.1.2
Enet phy init passed !
Link Status: Down
Link Status: Up
Link Speed:  1000Mbps
Link Duplex: Full duplex
IPv4 Address: 192.168.100.10
IPv4 Netmask: 255.255.255.0
IPv4 Gateway: 192.168.100.1
Please enter a target name(IP or URL):

Enter an IP or URL, and then press “Enter” to confirm
```
www.hpmicro.com
```

View log:

Pinging www.hpmicro.com [47.108.71.172] ..................
from 47.108.71.172 bytes=60 icmp_seq=0 ttl=48 time=33 ms
from 47.108.71.172 bytes=60 icmp_seq=1 ttl=48 time=33 ms
from 47.108.71.172 bytes=60 icmp_seq=2 ttl=48 time=33 ms
from 47.108.71.172 bytes=60 icmp_seq=3 ttl=48 time=33 ms