Remote Operation; Basic Gpib Concepts; Data And Interface Messages - ILX Lightwave LDX-36000 Series User Manual

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C H A P T E R
R O
EMOTE PERATION
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Test and measurement equipment with remote operation capability will generally
communicate through a GPIB interface. GPIB (General Purpose Interface Bus) is
the common name for ANSI/IEEE Standard 488.2 1987, an industry standard for
interconnecting test instruments in a system.
Everything that can be done from the front panel can also be done remotely, and
in some cases, with more flexibility. For instance, in remote mode, there is access
to functions and modes not available from the front panel, such as commands that
will increment (LAS:INC) or decrement (LAS:DEC) the current setpoint by a
predefined step value (LAS:STEP). The following sections explain the
fundamentals of operating the LDX-36000 Current Source remotely through the
GPIB interface.

Basic GPIB Concepts

The information in this basic concepts section is normally not necessary to
successfully operate the LDX-36000 through its GPIB interface because the host
computer's GPIB controller usually handles the details. However, it is a useful
perspective in understanding GPIB.

Data and Interface Messages

GPIB devices communicate with each other by sending data and interface
messages. Data contains device-specific information such as programming
instructions, measurement results, and instrument status. Each device has an
address number, and ignores all data traffic not addressed to it. Depending on its
content, data is often called a "device dependent message" or a "device
dependent command". Interface messages manage the bus, with functions such
as initializing the bus and addressing or unaddressing devices. In addition, some
individual bus lines are designated for this purpose.
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LDX-36000 Series
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