Addtron Technology manual WebNet User’s Guide

3.2Applying power

The AC adapter is connected to the power socket on the WebRJS board and power is switched on. The LED’s should start flashing after a few seconds, and after an additional few seconds the unit has finished booting.

3.3Assigning an IP Address

A WebNet module is, from the factory, configured to run in a so-called “Auto-IP mode”. The technical details of assigning an IP-address with Auto-IP mode are explained in section 3.3.1 below, but you may want to skip that section and proceed to the description of the necessary steps to assign the IP address, in section 3.3.2.

3.3.1Auto-IP – the details

The board has, from the factory, a hardware (MAC) address, but no IP-address. Auto-IP makes it listen to network packets for its own MAC address, and when the first IP-packet for that MAC address comes in, it takes the receiver-IP address from that packet and uses that as its IP address. To be able to send such a packet, an entry is added to the arp table of the computer, where the desired IP address is associated with the MAC address. Thus, to assign the WebNet an IP-address, the following steps should be carried out:

3.3.2Auto-IP – how to assign an IP address

The steps described here apply to Windows machines, but a similar procedure is possible on e.g. UNIX machines. Check your local flavour of arp by typing arp -? in a command prompt, in case of problems.

In this example, the desired IP address is 192.168.4.10 and the MAC address is (from the label on the WebNet module) 00-d0-c8-00-01-0d.

1.Open a command-line interpreter (DOS-prompt)

2.Make a static entry in the arp table by entering the command: arp -s 192.168.4.10 00-d0-c8-00-01-0d

3.Ping the WebNet board: ping 192.168.4.10

The ping command should result in 4 successive positive answers each starting with: Reply from 192.168.4.10. If something has gone wrong, the answers start with “Request timed out”.

If the pings responded successfully, the IP address is now assigned. Otherwise, check the following list of possible sources of error:

WebNet User’s Guide 13