R&S QAT100 User Manual page 32

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R&S QAT100
Identifying instruments in a network
If several instruments are connected to the network, each instrument has its own IP
address and associated resource string. The controller identifies these instruments by
the resource string.
VISA library
A VISA installation is a prerequisite for remote control using the LAN interface.
VISA is a standardized software interface library providing input and output functions to
communicate with instruments. High level programming platforms use VISA as an
intermediate abstraction layer.
The I/O channel (LAN or TCP/IP) is selected at initialization time by one of the follow-
ing:
●
The channel–specific address string ("VISA resource string")
●
An appropriately defined VISA alias (short name).
For more information about VISA, refer to the VISA user documentation.
VXI-11 protocol
The VXI-11 standard is based on the open network computing remote procedure call
(ONC RPC) protocol which in turn relies on TCP/IP at the network/transport layer. The
TCP/IP network protocol and the associated network services are preconfigured.
TCP/IP ensures connection-oriented communication, where the order of the
exchanged messages is adhered to and interrupted links are identified. With this proto-
col, messages cannot be lost.
SCPI compatibility
SCPI commands (standard commands for programmable instruments) are used for
remote control. The SCPI standard is based on standard IEEE 488.2 and aims at the
standardization of instrument-specific commands, error handling and the status regis-
ters. The tutorial "Automatic Measurement Control - A tutorial on SCPI and IEEE
488.2" from John M. Pieper (R&S order number 0002.3536.00) offers detailed informa-
tion on concepts and definitions of SCPI. The instrument supports the SCPI version
1999.
Commands that are not taken from the SCPI standard follow the SCPI syntax rules.
Communication ports
You have to open several ports in the firewall to be able to communicate via SCPI. By
default, these ports are already open on the R&S QAT. If you want to close these ports,
you can run a script that closes these ports.
●
To close the ports, run the
script .\firewall\firewall-disableaccess.bat.
Closing the ports disables remote control functionality.
●
To reopen the ports, run the script .\firewall\firewall-setting.bat.
User Manual 1179.3073.02 ─ 02
Remote control
Remote Control Interface and Protocol
32