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1257 User Manual
Computer Interfaces 4-6
EADS North America Defense
Test and Services, Inc.
©
2001
category on the third line would give the complete IP address,
gateway address, and the subnet mask. For example if the
remaining IP_Oct_2, IP_Oct_3, and IP_Oct_4 fields displayed
values of “16”, “30”, “35” respectively, the DHCP-assigned IP
address would be “172.16.30.35”. It is important to note that
while in DHCP mode, the values for the various octets can be
viewed but not changed.
Using Static Addressing
In Manual Mode, the user decides what static IP address, gateway,
and sub-net mask to use, and enters them manually. The first step
is to put the 1257 into Manual Set mode, to allow setting of the
TCP/IP parameters.
Before attempting to use static or manual addressing on a 1257,
several important things must be kept in mind:
•
Do not randomly assign an address to the 1257. Duplicate or
incorrect addresses on a central network can cause
unpredictable problems and failures that are difficult to identify
and trace. They also tend to be intermittent which further
compound troubleshooting efforts. If the 1257 will be used on
a central network, contact the network administrator for an
assignment or a block assignment of addresses.
•
Make sure that the assigned subnet mask for a 1257 system is
consistent with the class of network. For example a class C
network (i.e. “192.168.X.X”) would typically have a subnet
mask of “255.255.255.0”. A class B network (i.e. “172.16.X.X”)
would typically have a subnet mask of “255.255.0.0”.
•
Most private networks found inside commercial/industrial
environments are typically contiguous which means that one
instrument can communicate directly to other computers and
equipment without the assistance of an intermediate gateway.
In this situation, the gateway address need not be specified in
the 1257. If the 1257 exists in a network that has individual
subnets isolated by gateways or bridges, the gateway
parameters must also be specified or the 1257 will only be able
to communicate with computers and equipment local to its own
subnet.
To select manual mode, proceed as follows:
1. Press the top key, which will select line 1 (top line). Rotate the
knob until the top line reads:
>-----SETTINGS-----<
2. Select line 2 (next to top line) by pressing the second key.
Rotate the knob until the display shows line 2 as follows (lines