User guide

further configuration possibilities. This pattern is sent as long as the output

port is enabled.

See “Setting up Patterns - Concepts” on page 61 for more details.

• Alternating patterns consist of two patterns, one of which is pattern A (the A

half), the other is pattern B (the B half). Both patterns are of equal length, each

up to 16Mbit.

The Alternate Pattern Control dialog box lets you control when which pattern is

sent. See “Pattern Alternation - Procedures” on page 162.

When to Use Alternating Patterns

Alternating patterns can be used:

• To systematically insert errors in the bit stream at particular positions.

The error detector expects pattern A only. If you set up pattern B so that there

are only minor differences, when you run the test, the error detector will detect

the changed bits as errors.

• To see how long it takes your DUT to settle.

You can set up an easy-to-process output stream as the standard pattern, and

a difficult output stream as the alternate pattern (for example, all 0s for the

standard pattern, and alternating 1s and 0s as the alternate pattern). You can

then track how long it takes for your DUT to recover after the alternate pattern

has been sent.

Pattern Alternation - Procedures

The Alternate Pattern Control dialog box controls how the output stream switches

between the standard pattern and the alternate pattern.

You have the following possibilities for setting up alternating patterns:

Setting Up a Periodical Output

To configure the pattern generator to generate periodical data output:

Click Alt. Pattern and Aux In menu item from the PG Setup submenu to open

the Alternate Pattern Control dialog box.

Select one of the following options:

4 Setting up the Pattern Generator

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