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Operating Concepts
GPIB Operation
GPIB STATUS Indicators When the analyzer is connected to other instruments over GPIB, the GPIB STATUS
indicators in the instrument state function block light up to display the current status of
the analyzer.
R = remote operation
L = listen mode
T = talk mode
S = service request (SRQ) asserted by the analyzer
System Controller Mode The softkey activates the system controller mode. When in this
mode, the analyzer can use GPIB to control compatible peripherals, without the use of an
external computer. It can output measurement results directly to a compatible printer or
plotter, store instrument states using a compatible disk drive, or control a power meter for
performing service routines. The power meter calibration function requires system
controller or pass control mode.
Talker/Listener Mode The softkey activates the talker/listener mode, which is the mode of
operation most often used. In this mode, a computer controller communicates with the
analyzer and other compatible peripherals over the bus. The c omputer s ends c ommands or
instructions to and receives data from the analyzer. All of the capabilities available from
the analyzer front panel can be used in this remote operation mode, except for control of
the power line switch and some internal tests.
Pass Control Mode The softkey activates the third mode of GPIB operation: the pass
control mode. In an automated system with a computer controller, the controller can pass
control of the bus to the analyzer on request from the analyzer. The analyzer is then the
controller of the peripherals, and can direct them to plot, print, or store without going
through the computer. When the peripheral operation is c omplete, c ontrol is passed back to
the computer. Only one controller can be active at a time. The computer remains the
system controller, and can regain control at any time.
Preset does not affect the selected controller mode, but cycling the power returns the
analyzer to talker/listener mode.
Information on compatible peripherals is provided in the “Options and Accessories”
chapter of the reference guide.
SYSTEM CONTROLLER
TALKER/LISTENER
USE PASS CONTROL