# Pattern Length and Symbol Patterns

From the Pattern drop-down list, you can select:

- Auto Detect — The oscilloscope automatically determines the pattern length and pattern by looking for at least two error-free copies of an identical repeating symbol pattern in acquisition memory.

- Known Pattern — Lets you select the pattern from a drop-down list of known patterns.

  Use the Invert option to detect an inverted version of the known pattern.

- Pattern File — Lets you load a pattern file that tells the oscilloscope the pattern length and pattern to measure against. Click Browse... to select the pattern file.

  Use the Invert option to detect an inverted version of the loaded pattern.

  Included with the Infiniium software are some pattern files that are also included with BERTs. The files are located in the C:\Program Files\Keysight\Infiniium\Demo\Patterns folder. See:

  - Provided NRZ Pattern Files
  - Provided PAM3 Pattern Files
  - Provided PAM4 Pattern Files