Arduino Ethernet not visible in Router Status

Question

I am trying to send over my code to my Arduino Ethernet board via the Adafruit FTDI friend. I am using the 1.0.4 version of the IDE and have the following settings:

Tools -> Board -> Arduino Ethernet Tools -> Serial Port -> COM 3

The sketch is sent over to the board without problems or errors... however I am unable to see the IP of the board when i check my "attached devices" in my routers settings menu.

Here is a snip of the code I used:

 byte ip[] = { 192, 168, 9, 199 }; //Manual setup only
 byte gateway[] = { 192, 168, 9, 1 }; //Manual setup only
 byte subnet[] = { 255, 255, 255, 0 }; //Manual setup only
 // if need to change the MAC address (Very Rare)
 byte mac[] = { 0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0xED };
 EthernetServer server = EthernetServer(199); //port 199
void setup(){
 Serial.begin(9600);
 //Pins 10,11,12 & 13 are used by the ethernet shield
 pinMode(2, OUTPUT);
 pinMode(3, OUTPUT);
 pinMode(4, OUTPUT);
 pinMode(5, OUTPUT);
 pinMode(6, OUTPUT);
 pinMode(7, OUTPUT);
 pinMode(8, OUTPUT);
 pinMode(9, OUTPUT);
 //Ethernet.begin(mac);
 Ethernet.begin(mac, ip, gateway, subnet); //for manual setup
 server.begin();
 Serial.println(Ethernet.localIP());
}

Here is a screen shot of the router settings:

enter image description here

And this is my Arduino ethernet hookup:

enter image description here

What could I be missing?

• PeterJ: I've seen some routers where the attached devices list is only a list of devices that have requested a DHCP address. Does it appear on the list / work if you use the commented out Ethernet.begin(mac) line?
• Connor Wolf: Try pinging the IP you're specifying in your code. Open a command-prompt window, and ping <ip here>. For example: ping 192.168.9.199.

Answer 1

On some routers the attached devices list only contains a list of devices that have requested a DHCP address. Try the following change to go back to using a DHCP address rather than a manual setup:

Ethernet.begin(mac);
//Ethernet.begin(mac, ip, gateway, subnet); //for manual setup

Answer 2

Most routers only show devices that have been granted a DHCP lease and since your Arduino has a static IP-address it won't show. You can see the device on your PC once you have contacted it at least once throught the ARP-table:

Here is an example ARP-table (Linux, but Windows is similar):

€ arp -a
? (192.168.0.170) at c8:60:00:3b:a8:7e [ether] on eth0
? (192.168.0.1) at bc:05:43:e7:36:92 [ether] on eth0
? (192.168.0.143) at 08:00:27:a6:a2:e7 [ether] on eth0