Pattern Declaration
- Updated2025-10-09
- 2 minute(s) read
The required pattern declaration defines the sequence of pattern vectors and defines the pins and pin groups to which the pattern applies using the following syntax:
{
vector_statement1; [// comment]
vector_statement2; [// comment]
...
}
where pattern_name (required) and pin_item<n> are valid identifiers.
Conditions
The following conditions apply to the pattern declaration:
- The pattern declaration must be the last declaration in the pattern file.
- The pattern file can contain only one pattern declaration.
- The pattern_name must begin with a letter or underscore (_) and is limited to A-Z, a-z, 0-9, or _ characters. The pattern name is independent from the filename of the pattern file.
- A
pin_item is a reference to a pin or pin group defined in the pin and channel map file used to compile the pattern. The text pattern file does not reference the pin and channel map file directly. The
pin_item identifier can include one of the following optional format specifiers to set the display format for pin groups:
- :b — binary or symbolic (default)
- :u — unsigned integer
- :x — hexadecimal
- All pin_items must resolve to a mutually exclusive set of pins. Two or more pin_items must not resolve to the same pin or set of pins.
- You cannot duplicate a pin_item in a pattern declaration.
Keep Alive Pattern Declaration
Keep alive patterns use the following pattern declaration syntax:
keep_alive_pattern pattern_name (pin_item1, pin_item2:b, …)
{
vector_statement1; [// comment]
vector_statement2; [// comment]
...
}
where pattern_name (required) and pin_item<n> are valid identifiers.
Conditions
The conditions for standard pattern declarations apply to pattern declarations for keep alive patterns. The following additional conditions apply to keep alive patterns:
- A keep alive pattern can include up to only 16 vectors.
- You can use only dashes (-) for time sets. Keep alive patterns execute the same time set used on the vector on which you executed the keep_alive opcode to begin the keep alive pattern.
- You can use only the keep_alive and repeat opcodes in keep alive patterns.
- You cannot use labels in keep alive patterns.
- You can use only 0, 1, X, and - for the pin state data in a keep alive pattern.
Related Information
- Pattern Grid View
Click the Grid tab on the pattern document toolbar to launch the pattern grid view. Use this view to see components of the binary pattern file, including time sets, labels, opcodes, vector numbers, pin state data that indicates drives and compares, comments for each vector, exported labels, and comments from the top of the file. Use the pattern waveform view for a graph-based representation of the pattern. You can select and right-click vectors in the pattern grid view and select Show Vectors in Waveform View from the context menu to launch the pattern waveform view. You can also click the Waveform tab on the pattern document toolbar to launch the pattern waveform view. An asterisk (*) next to a filename in the Project Explorer window and in the document tab indicates that the file has been modified but not saved.
- Vector Statement
The vector statement specifies the label for the vector, the opcodes to execute, the data to drive to or compare from the DUT pins, and the time set that contains the timing information to apply to the data using the following syntax:
- Flow Control Opcodes
- Keep Alive Patterns
Keep alive patterns prevent interference with clocks and PLLs during certain actions in the Digital Pattern Editor. Use them to maintain stability while performing other tasks.