MicroNet is a network connection manager library for Arduino and PlatformIO.

It provides:

• A unified interface for Wi-Fi or Ethernet (switch from one to the other by changing only a few lines of code).
• DHCP client support.
• mDNS (Bonjour) support.
• A captive Wi-Fi configuration portal.

• ESP32

• Wiznet Ethernet controller chips
  • Tested with the M5Stack Atom POE

#include <Arduino.h>
#include <MicroNetWifi.h>
MicroNetWifi myMicroNet;
void setup(){
    myMicroNet.begin("myName");
}
void loop() {
   myMicroNet.update()
}

#include <Arduino.h>
#include <MicroNetEthernet.h>
MicroNetEthernet myMicroNet;
void setup(){
    SPI.begin(22, 23, 33, 19); // ATOM LITE POE
    Ethernet.init(19);  // ATOM LITE POE
    // DO NOT CALL Ethernet.begin(), call the following instead:
    myMicroNet.begin("myName");
}
void loop() {
   myMicroNet.update()
}

#include <Arduino.h>
#include <MicroNetEthernet.h>
MicroNetEthernet myMicroNet(MicroNetEthernet::Configuration::ATOM_POE_WITH_ATOM_LITE);
void setup(){
    myMicroNet.begin("myName");
}
void loop() {
   myMicroNet.update()
}

#include <MicroNetEthernet.h>
MicroNetEthernet myMicroNet;

#include <MicroNetEthernet.h>
MicroNetEthernet myMicroNet(MicroNetEthernet::Configuration::ATOM_POE_WITH_ATOM_LITE);

Available presets:

MicroNetEthernet::Configuration::ATOM_POE_WITH_ATOM_LITE // Atom POE with Atom Lite
MicroNetEthernet::Configuration::ATOM_POE_WITH_ATOMS3 // Atom POE with Atom S3 

For Wi-Fi:

#include <MicroNetWiFi.h>
MicroNetWiFi myMicroNet;

If you are using Generic Ethernet, configure the hardware before starting MicroNet (do NOT call Ethernet.begin()).

Example configuration for an Atom Lite POE:

SPI.begin(22, 23, 33, 19); // ATOM LITE POE
Ethernet.init(19);        // ATOM LITE POE

If you are using a Preset Ethernet Configuration there is nothing to configure, the hardware will automatically be called when calling begin() (see below).

Start MicroNet with myMicroNet.begin() - the method will only return once it gets an IP from the DHCP server:

myMicroNet.begin(name);

• name — C string (const char*) used as the device and mDNS name.

• For Wi‑Fi:
  • MicroNet attempts to connect to the configured access point.
  • If it fails, a captive configuration portal is opened using the provided name.
  • Connect to this portal to enter Wi‑Fi credentials.
• For Wi‑Fi and Ethernet:
  • Once connected to the network, MicroNet requests an IP address via DHCP.
  • After an IP is obtained, the device registers its mDNS name.

The myMicroNet.update() method performs periodic network maintenance tasks and must be called as often as possible:

    myMicroNet.update();

The maximum length of the device name (including the null terminator), that you should respect, is defined by:

MICRO_NET_NAME_MAX_LENGTH

You can append part of the MAC address to an existing C string to generate a unique name:

myMicroNet.appendMacToCString(prefix, destMaxSize, numBytes)

• prefix — Destination C string (char*) containing the name prefix.
• destMaxSize — Maximum size of the destination buffer (size_t).
• numBytes — Number of MAC address bytes (uint8_t) to append (each byte adds two hexadecimal characters).

Example producing a name like atom-932AE4:

  char myName[MICRO_NET_NAME_MAX_LENGTH] = "atom-"; // name prefix
  myMicroNet.appendMacToCString(myName, MICRO_NET_NAME_MAX_LENGTH, 3);
  // START MicroNet with the custom name
  myMicroNet.begin(myName);

Copies the device MAC address into the provided buffer:

myMicroNet.copyMac(mac);

• mac — A 6‑byte array (uint8_t[6]) that will receive the MAC address.

Returns the current IP address of the device:

IPAddress ip = myMicroNet.getIP();

The resolveName() method will resolve an mDNS host name to its IP. The method only returns if the host is found! Do not append .local to the hostName.

IPAddress ip = myMicroNet.resolveName(hostName);

• hostName — C string (const char*) containing the mDNS hostname.

Announce TCP service:

myMicroNet.announceTCPService(serviceName, servicePort);

• serviceName — C string (const char*) with the service name.
• servicePort — TCP port number (uint16_t).

Announce UDP service:

myMicroNet.announceUDPService(serviceName, servicePort);

• serviceName — C string (const char*) with the service name.
• servicePort — TCP port number (uint16_t).