Rohde & Schwarz SMBV100A, Руководство по эксплуатации

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Remote Control Basics
R&S
®
SMBV100A
460 Operating Manual 1176.8016.02 ─ 17
SCPI (Standard Commands for Programmable Instruments)
SCPI commands - messages - are used for remote control. Commands that are not
taken from the SCPI standard follow the SCPI syntax rules. The instrument supports
the SCPI version 1999. The SCPI standard is based on standard IEEE 488.2 and aims
at the standardization of device-specific commands, error handling and the status reg-
isters. 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.
Tables provide a fast overview of the bit assignment in the status registers. The tables
are supplemented by a comprehensive description of the status registers.
6.1.1 VISA Libraries
VISA is a standardized software interface library providing input and output functions to
communicate with instruments. Thus, you can configure the interface and must not
adjust the application program to the used interface. The I/O channel (LAN or TCP/IP,
USB, GPIB,...) is selected at initialization time with the channel-specific address string
("VISA resource string"), or by a defined VISA alias (short name). See also
Chap-
ter 6.1, "Remote Control Interfaces and Protocols" , on page 459 for an overview.
Instrument access via VXI-11 or HiSLIP protocols is achieved from high level program-
ming platforms using VISA as an intermediate abstraction layer. VISA encapsulates
the low-level VXI or GPIB function calls and thus makes the transport interface trans-
parent for the user.
A VISA installation is a prerequisite for remote control using the following interfaces:
●
LAN Interface using Chapter 6.1.3, "LAN Interface" , on page 461
●
LAN interface using Chapter 6.1.3.2, "VXI-11 Protocol" , on page 463
●
Chapter 6.1.4, "USB Interface" , on page 464
●
Chapter 6.1.6, "GPIB Interface (IEC/IEEE Bus Interface)" , on page 465
●
Chapter 6.1.5, "Serial Interface" , on page 465
Instrument access via the LAN socket protocol or GPIB connections can be operated
both, with or without the VISA library.
See also Chapter 6.1.3.3, "Socket Communication" , on page 463 and Chapter 6.1.6,
"GPIB Interface (IEC/IEEE Bus Interface)" , on page 465.
For more information about VISA, refer to the user documentation.
6.1.2 Messages
The messages transferred on the data lines are divided into the following categories:
●
Interface messages
Interface messages are transmitted to the instrument on the data lines, with the
attention line being active (LOW). They are used to communicate between the con-
troller and the instrument. Interface messages can only be sent by instruments that
have GPIB bus functionality. For details see the sections for the required interface.
Remote Control Interfaces and Protocols