User guide

Only available on the Error Detector Pattern page. Enables the error detector's bit
recovery mode. For details see “Understanding Bit Recovery Mode” on page
195.
Software-Generated PRBS
Software-Generated PRBS - Concepts
Software-generated patterns are PRBS patterns that can be modified. They are
calculated by the Serial BERT software and then loaded to the memory, from which
the necessary output is generated. As such, they are closely related to user
patterns, with the exception that they cannot be edited in the Pattern Editor
window.
When to Test with Software-Generated PRBS
You can use these patterns for any application where random data and an even
number of bits is required.
In addition, you can vary the mark density or zero substitution to test the
influence on the BER. This allows potential problems like baseline wander, for
instance, to be fully characterized.
How the Software Generates PRBS
When you set up a software-generated pattern, the Serial BERT calculates the
required pattern and loads this into the memory. From here, the memory is read bit
by bit (identically as for memory-based patterns), and the corresponding output is
generated.
See also “How the Serial BERT Generates Memory-Based Patterns” on page 69.
Range of Software-Generated PRBS Patterns
The Serial BERT supports the following 2^n PRBS patterns:
Setting up Patterns 3
Agilent J-BERT N4903B High-Performance Serial BERT 91
Bit Recovery Mode / BRM