Step 2: Connect Power and Ethernet
The primary power for the ARMweb is 3.3V provided
from a linear regulator. The input power for the PCB may be 5V regulated
supply or a 6-9V unregulated supply, with a current rating of 300 mA or
more.
The ARMweb will configure
itself
with an IP
address assigned by a DHCP server. IP addresses are the way networks
organize themselves. If there is no DHCP server found, the ARMweb will provide limited
DHCP services, assuming a single connection on Ethernet with a PC
using either a hub or cross-over (see the next section).
Assuming a DHCP server is available and you are running on a Windows machine, you can use the Windows NetBIOS Name Service. In which case you can find the ARMweb initially with http://armweb. Note that some administrators disable this service.
Most DHCP servers will list client machines which have been assigned an IP address. An example is the display from a Dlink Firewall that is also providing DHCP services.
So in this case the ARMweb can be found at http://192.168.0.2
Also during startup information is sent out TXD0 of the CPU, and this can be captured on a SparkFun USB breakout board or similar. On rev 2 of the hardware a connector for this USB breakout board will be available. Among the information is the IP address that is used-
A minimal configuration is an
ARMweb connected to a PC with a cross-over cable. This can be useful for
configuring an ARMweb prior to connecting with a larger
network, In this case no DHCP server will be found, and after
10 seconds the ARMweb will provide limited DHCP services, assigning an IP address to the PC. However,
this miniDHCP service will be terminated if the ARMweb is ever connected
to a network with a DHCP server. To restore this miniDHCP service and
the factory defaults, hold the push-button for 5 seconds while cycling the power.
The ARMweb will normally be located at http://192.168.0.50 unless it has been reconfigured before, in which case it will use the last assigned IP address.
If you can not find the ARMweb at http://192.168.0.50 or http://ARMweb as above, then you can locate its IP address with the DOS command line program IPCONFIG. The ARMweb will appear as the default gateway in this case. Also if your ARMweb has been connected to a network serviced by a DHCP it will not function as a limited DHCP server (this would cause confusion in a large network). In order to get the limited DHCP service started again, you will need to restore the ARMweb to its default settings which can be done by holding the pushbutton switch during power up.
If you're not seeing this make sure your PC Network configuration is set to Obtain an IP address automatically. (Control Panel -> Network Connections -> Local Area Network -> Properties -> TCPIP -> Properties)