Agilent Technologies E4406A VSA manual Overview of the GPIB Bus, GPIB Instrument Nomenclature

Programming Fundamentals

Overview of the GPIB Bus

Overview of the GPIB Bus

GPIB Instrument Nomenclature

An instrument that is part of an 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 your 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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