Ethernet

Digital I/O
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Advanced I/O
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Bits and Bytes
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Serial Comm.

Ethernet
Ethernet (Server)
Ethernet (Client)
Servo Motor
Stepping Motor
Character LCD
EEPROM
SPI
I²C (Wire)
SD Card
SD (File Operations)
Periodic Operation
Clock (RTC)
Utility

This is a library for Ethernet initialization. It is necessary to use Ethernet for both client and server. Specify #include <Ethernet.h> for use.

begin

Description

Initializes the Ethernet library and network settings. The DHCP automatically obtains an IP address, DNS, default gateway, and subnet mask.

Syntax

int Ethernet.begin(mac)
Ethernet.begin(mac, ip)
Ethernet.begin(mac, ip, dns)
Ethernet.begin(mac, ip, dns, gateway)
Ethernet.begin(mac, ip, dns, gateway, subnet)

Parameters

mac: MAC address (array of 6 bytes)
ip: IP address (array of 4 bytes)
dns: Name server address (array of 4 bytes)
gateway: Default gateway address (array of 4 bytes)
subnet: Subnet mask (array of 4 bytes)

Returns

If Ethernet.begin(mac) is successful = 1; if failure = 0. Others are none.

localIP

Description

Obtains the IP address of the board.

Syntax

IPAddress Ethernet.localIP()

Parameters

None

Returns

The IP address

maintain

Description

Allows for the renewal of DHCP leases.

Syntax

Ethernet.maintain()

Parameters

None

Returns

0: Nothing happened
1: Renew failed
2: Renew success
3: Rebind fail
4: Rebind success

Connect with DHCP, and then display the IP address.

#include <Arduino.h>
#include <Ethernet.h>
 
byte mac[] = {  
  0x00, 0xAA, 0xBB, 0xCC, 0xDE, 0x02 };
// Initialize the Ethernet client library
// with the IP address and port of the server 
// that you want to connect to (port 80 is default for HTTP):
EthernetClient client;
 
void setup()
{
    Serial.begin(9600);
    while(!Serial.available()); // wait to press key.
     
    // start the Ethernet connection:
    if (Ethernet.begin(mac) == 0) {
        Serial.println("Failed to configure Ethernet using DHCP");
        while(1);
    }
    // print your local IP address:
    Serial.println(Ethernet.localIP());
}
 
void loop() {
}