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LAN Connection
To use the LAN interface, the IP address of the unit must be known. On the supplied CD-ROM is a
guide to the LXI Discovery Tool which provides links to the latest version of the tool and associated
downloads. The tool is a Windows PC application which can be used to display the IP addresses or
host names of all connected devices that comply with the VXI-11 protocol or support multicast
Domain Name System (mDNS) records.
Connecting via a router is recommended as this is significantly quicker to assign an IP address;
connecting directly to the PC will begin to assign an IP address only after a 30 second DHCP time-
out. Double clicking on any entry in the list of devices discovered will open the PC's web browser
and display the Home page of that device.
There are also tools for LAN discovery included as part of the National Instruments Measurement
and Automation Explorer package and the Agilent Vee application.
It is also possible to discover the assigned IP address from the Help menu. On single channel
instruments, press the Help key, select option 3 and scroll down to the IP address. For dual
channel instruments, press the Utility key followed by the Help soft-key, then select option 3 and
scroll down to the IP address.
Web Server; Configuration Password Protection
The unit contains a basic web server. This provides information on the instrument and allows it to
be configured. The Configure page can be password protected to deter unauthorised changes to
the remote operation configuration; the default configuration is ‘no password’.
The Configure page itself explains how to set the password. The password can be up to 15
characters long. The password will, however, be reset to the default (no password) if the front panel
is used to reset all the LAN parameters to their factory default.
The web pages also have an ‘Identify’ function which allows the user to send an identifying
command to the instrument which causes its display to flash until the command is cancelled.
ICMP Ping Server
The unit contains an ICMP server allowing the instrument to be ‘pinged’ via either its host name or
IP address.
VXI-11 Discovery Protocol
The instrument has very limited support of VXI-11 which is sufficient for the discovery protocol and
no more.
The instrument implements a Sun RPC Port-mapper on TCP port 111 and UDP port 111 as defined
in RPC1183. The calls supported are: NULL, GET PORT and DUMP.
On TCP port 1024 a very simple VXI-11 protocol is implemented sufficient only for instrument
discovery. This implements the following calls: CREATE LINK, DEVICE_WRITE, DEVICE_READ
and DESTROY_LINK.
Once a link has been created anything written to the device is ignored and any read from the device
returns the identification string as would be expected from a “*IDN?” of the form
‘Manufacturer, Model, Serial No., XX.xx – YY.yy’ – ZZ.zz
where ‘XX.xx’ is the revision of the main firmware and ‘YY.yy’ is the revision of the remote interface
firmware and ‘ZZ.zz’ is the revision of the USB flash drive firmware.
mDNS and DNS-SD Support
Multicast DNS provides DNS services even on networks without a central DNS server (or DHCP
server). This simplifies the setting up of a simple LAN using meaningful hostnames instead of a
raw IP address. With service discovery it becomes straightforward for the device to be discovered
and the services it provides.
The services provided by the instrument are http (_http._tcp) and lxi (_lxi._tcp).
