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Model 845-M Programmer’s Manual V1.1 2011
For instance, if the instrument has the IP address 192.168.1.50,
TCPIP::192.168.1.50::inst0::INSTR
is the valid
resource name. Specification of inst0 in the resource name is optional. In this example, also
TCPIP::192.168.1.50::INSTR
is therefore a valid resource name.
TCPIP designates the network protocol used and INSTR indicates that the VXI-11 protocol is used. If several
instruments are connected to the network, each instrument has its own IP address and associated resource
name. The controller identifies these instruments by means of the resource name.
Using Sockets LAN
Sockets LAN is a method used to communicate with the signal generator over the LAN interface using the
Transmission Control Protocol/Internet Protocol (TCP/IP). A socket is a fundamental technology used for
computer networking and allows applications to communicate using standard mechanisms built into network
hardware and operating systems. The method accesses a port on the signal generator from which bidirectional
communication with a network computer can be established. Sockets LAN can be described as an internet
address that combines Internet Protocol (IP) with a device port number and represents a single connection
between two pieces of software. The socket can be accessed using code libraries packaged with the computer
operating system. Two common versions of socket libraries are the Berkeley Sockets Library for UNIX systems
and Winsock for Microsoft
operating systems.
Your signal generator implements a socket Applications Programming Interface (API) that is compatible with
Berkeley socket for UNIX systems, and Winsock for Microsoft systems. The signal generator is also compatible
with other standard sockets APIs. The signal generator can be controlled using predefined SCPI functions once
the socket connection is established in your program. Socket connection is available on port 18.
Using and Configuring VXI-11 (VISA)
The signal generator supports the LAN interface protocol described in the VXI- 11 standard. VXI- 11 is
an instrument control protocol based on Open Network Computing/Remote Procedure Call (ONC/RPC)
interfaces running over TCP/IP.
A range of standard software such as NI-VISA or Agilent IO Config is available to setup the computer/signal
generator interface for the VXI- 11 protocol. Please refer to the applicable software user manual and
documentation for information on running the program and configuring the VXI-11 interface. The program
is used to configure the LAN client. Once the computer is configured for a LAN client, you can use the VXI- 11
protocol and the VISA library to send SCPI commands to the signal generator over the LAN interface.
