Programming The Trigger System; In This Subsection; Generalized Trigger Model; Overview - HP 8360 User Handbook Manual

Programming the
Trigger System

In This Subsection

Generalized Trigger
Model
This subsection discusses the layered trigger model used in SCPI
instruments. It also outlines some commonly encountered trigger
configurations and programming methods. Trigger system topics are
explained in the following paragraphs:
Generalized Trigger These paragraphs explain the structure and
Model components of the layered trigger model used in
all SCPI instruments.
Common Trigger These paragraphs explain the INIT and TRIG
Configurations configurations implemented in the synthesizer.
Trigger Command These paragraphs provide condensed definitions
Definitions for the keywords used in this subsection.
Understanding trigger systems requires more technical expertise than
most other topics covered in this section. If you find this subsection
difficult, keep in mind that you do not have to program the trigger
system to make measurements or output signals. Using MEASure,
READ, or INITiate, you can avoid having to learn the information in
this subsection.

Overview

An instrument trigger system synchronizes instrument actions
with specified events. An instrument action may be to make a
measurement or source an output signal. The events used to
synchronize these actions include software trigger commands,
changing signal levels, and pulses on BNC connectors.' The trigger
system also lets you specify the number of times to repeat certain
actions, and delays between actions.
Figure l-35 shows a simplified view of the generalized SCPI trigger
model. Instruments may implement some or all of this model, to
accommodate varying needs. Each unshaded block in Figure l-35
trigger state.
represents a particular
allows an arbitrary number of event- detection states. Note that
there can be two paths into a state and two paths out of a state.
These are called the downward entrance and exit, and the upward
Upward
entrance and exit.
downward
means moving towards instrument actions.
An instrument moves between adjacent states, depending on its
internal conditions and the commands that you send. When you first
turn on power to an instrument, it is in the idle state. You can force
the instrument to the idle state using : ABORt or *RST. The initiate
and event detection trigger states are essentially a list of conditions
that must be satisfied to reach the adjacent states. The sequence
The generalized trigger model
means moving towards the idle state and