User`s guide

Agilent VISA User’s Guide 147
command bytes
GPIB commands encoded as individual bytes. Also called
GPIB commands or interface messages.
commander
In test- system architectures, a device that has the ability
to control another device. In a specialized case, a
commander may also be the device that has sole control
over another device (as with the VXI Commander/Servant
hierarchy).
commander session
A session that communicates to the interface’s
commander. Commander sessions are used when an
interface is in a non- Controller role.
communication channel
A communication path between a software element and a
resource. In VISA, “communication channel” is
synonymous with “session.” Every communication channel
in VISA is unique.
Connection Expert
An Agilent software utility that helps you quickly
establish connections between your instruments and your
PC. It also helps you troubleshoot connectivity problems.
Connection Expert is part of the Agilent IO Libraries
Suite product.
Controller
A device (typically a computer) used to communicate with
another device or devices (typically instruments). The
Controller is in charge of communications and device
operation; it controls the flow of communication and
performs addressing and other bus management functions.