User guide

User-Defined Sequences
User-Defined Sequences - Concepts
This section describes the basics of user-defined sequences.
A sequence is created and maintained by means of the Sequence Editor that can
be enabled from the Pattern window.
A sequence consists of up to 120 blocks than can be looped. Each block can
generate a pause signal (constant 0 or 1), a divided clock signal, a 2^n -1 PRBS, or
a user pattern.
Single or multiple blocks can be looped. The sum of the blocks and the counted
loops must not exceed 120. An overall loop restarts the sequence after it has come
to its end.
When to Use a Sequence
You may wish to test a device that uses a certain protocol for processing data.
For example, the device might expect synchronization data, a preamble, payload
data, and a suffix.
All this can be provided by a user-defined sequence.
How a Sequence is Defined
The sequence is defined by a SequenceExpression which is formulated in its own
language, checked by the Sequence Editor.
The SequenceExpression specifies:
• the sequence start (and break) conditions
• the blocks, their contents, and trigger output
• the loops
You can inspect the contents of the SequenceExpression in the Properties dialog
of the Sequence Editor.
The SequenceExpression uses the following keywords:
Version=
optional
3 Setting up Patterns
96 Agilent J-BERT N4903B High-Performance Serial BERT