Overview Of Gpib (Option A4H) - Agilent Technologies ESA Series User's/Programmer's Reference

Programming Fundamentals

Overview of GPIB (Option A4H)

Overview of GPIB (Option A4H)
GPIB Instrument Nomenclature
An instrument that is part of a GPIB network is categorized as a listener, talker, or
controller, depending on its current function in the network.
Listener A listener is a device capable of receiving data or commands
from other instruments. Any number of instruments in the GPIB
network can be listeners simultaneously.
Talker A talker is a device capable of transmitting data or commands to
other instruments. To avoid confusion, an GPIB system allows
only one device at a time to be an active talker.
Controller A controller is an instrument, typically a computer, capable of
managing the various GPIB activities. Only one device at a time
can be an active controller.
GPIB Command Statements
Command statements form the nucleus of GPIB programming. They are
understood by all instruments in the network. When combined with the
programming language codes, they provide all management and data
communication instructions for the system. Refer to the programming language
manual and your computers I/O programming manual for more information.
The seven fundamental command functions are as follows:
• An abort function that stops all listener/talker activity on the interface bus, and
prepares all instruments to receive a new command from the controller.
Typically, this is an initialization command used to place the bus in a known
starting condition (sometimes called: abort, abortio, reset, halt).
• A remote function that causes an instrument to change from local control to
remote control. In remote control, the front panel keys are disabled except for
the Local key and the line power switch (sometimes called: remote, resume).
• A local lockout function, that can be used with the remote function, to disable
the front panel Local key. With the Local key disabled, only the controller (or a
hard reset by the line power switch) can restore local control (sometimes called:
local).
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