AsyncDNSServer_STM32 for STM32 using builtin LAN8742A Ethernet

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AsyncDNSServer_STM32 for STM32 using builtin LAN8742A Ethernet

Post by khoih-prog »

AsyncDNSServer_STM32 Library

How To Install Using Arduino Library Manager

Why do we need this Async AsyncDNSServer_STM32 Library

- Using asynchronous network means that you can handle more than one connection at the same time
- You are called once the packet is ready
- After connecting to a UDP server as an Async Client, you are immediately ready to handle other connections while the Client is taking care of receiving the UDP responding packets in the background.
- You are not required to check in a tight loop() the arrival of the UDP responding packets to process them.
- Speed is OMG

Initial Releases v1.0.0

1. Initial coding to port Develo's ESPAsyncDNSServer Library to STM32 boards using built-in LAN8742A Ethernet. More supports will be added gradually later, such as other Ethernet / WiFi shields.
2. Add more examples.
3. Add debugging features.

Currently Supported Boards

1. Nucleo-144 (F429ZI, F746ZG, F756ZG, F767ZI)
2. Discovery STM32F746G-DISCOVERY
3. Any STM32 boards with enough flash/memory and already configured to run LAN8742A Ethernet.

Sample Code

This is the AsyncDNSServer_STM32 example

Code: Select all

   Currently support
   1) STM32 boards with built-in Ethernet (to use USE_BUILTIN_ETHERNET = true) such as :
      - Nucleo-144 (F429ZI, F767ZI)
      - Discovery (STM32F746G-DISCOVERY)
      - STM32 boards (STM32F/L/H/G/WB/MP1) with 32K+ Flash, with Built-in Ethernet,
      - See How To Use Built-in Ethernet at (

#include "defines.h"

#include <AsyncDNSServer_STM32.h>
#include <AsyncWebServer_STM32.h>

const byte DNS_PORT = 53;

IPAddress apIP;

AsyncDNSServer dnsServer;

AsyncWebServer server(80);

void handleNotFound(AsyncWebServerRequest *request)
  String message = "Hello World!\n\n";
  message += "URI: ";
  message += request->url();

  request->send(200, "text/plain", message);

void setup()
  Serial.println("\nStart AsyncDNSServer_STM32 on " + String(BOARD_NAME));

  // start the ethernet connection and the server
  // Use random mac
  uint16_t index = millis() % NUMBER_OF_MAC;

  // Use Static IP
  //Ethernet.begin(mac[index], ip);
  // Use DHCP dynamic IP and random mac

  apIP = Ethernet.localIP();

  // modify TTL associated  with the domain name (in seconds)
  // default is 60 seconds
  // set which return code will be used for all other domains 
  // (e.g. sending ServerFailure instead of NonExistentDomain will reduce number of queries
  // sent by clients). Default is AsyncDNSReplyCode::NonExistentDomain

  // start DNS server for a specific domain name
  dnsServer.start(DNS_PORT, "*", apIP);



  Serial.print(F("HTTP EthernetWebServer is @ IP : "));

void loop() 

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