HP 8360, User Handbook Manual

Page: 142 / 508

the sweep is initiated. This can happen on a continuous basis
: CONT ON) or on a demand basis : CONT OFF). The
functions of continuous and single sweeps are handled by this
command. When the
ON command is given, the sweep
is continuously re-initiated. When in the OFF state, the sweep is
initiated with the
command.
Once initiated, the
wait for trigger
state is entered. Here, the trigger
signal selected by the TRIG : command is examined until a
TRUE condition is detected. These trigger signals are:
BUS
This signal is always TRUE.
This is the external trigger input jack. A positive
transition on this jack constitutes a TRUE signal.
This signal is the HP-IB <get> (Group Execute
Trigger) message or a
command.
When a TRUE signal is found, the sweep is actually started.
The act of producing the sweep in some cases involves the use
of trigger signals. For example, the stepped and list sweeps
have modes that allow triggering for point-to-point advancement
through the sweep. These trigger signals are selected by individual
TRIG: commands in the appropriate subsystems (i.e.
LIST:TRIGger:SOURce and SWEep:TRIGger:SOURce). The
definition of these signals in the synthesizer cause the sweep to jump
to the next point when the signal becomes TRUE, therefore the
first point in the list or stepped sweeps is produced immediately
upon starting the sweep. Receiving
a
trigger signal at the last point
causes the IDLE state to be re-entered. Analog sweeps do not use
the trigger signals during the sweep (although the trigger signals are
needed to start the sweep as described).
The command resets any sweep in progress and immediately
returns the instrument to the IDLE state.
The , and commands indicate a complete operation
at the end of the sweep upon re-entry into the IDLE state.
Advanced Trigger Configurations
Because the SCPI layered trigger model is expandable, many more
complex trigger configurations are possible.
Trigger Keyword The following paragraphs contain condensed definitions of the
Definitions
keywords used in the command tables. Many of the commands in
trigger related subsystems are
event commands.
Remember that
event commands cannot be queried. Similarly, event commands
have no related
actions or settings. Event commands cause a
particular action to take place inside the synthesizer.
l-l 12 Getting Started Programming