Constraints Editor
Initializing Shift Registers
You can use the Shift Register Initialization dialog box to initialize a shift register. This sets the initial state of the shift register.
Use the INIT constraint sparingly. Initialization should be handled as part of the HDL code whenever possible.
To Initialize a Shift Register
  1.  Open the Shift Register Initialization dialog box.
  2.  To limit the shift register instances listed in the SR Instance list, enter a filter string in the Filter box and click Find. For example, to list only SRL16 instances containing the string "listb," type *listb* in the Filter box. The filter is not case sensitive.
  3.  From the SR Instance list, select the shift register instance to initialize.
  4.  In the Comment box, enter a comment for this initialization entry.
  5.  In the INIT string box, enter the initial value to be stored in the specified SRL16.
This creates an INIT constraint for selected shift registers.The new constraint appears in the current Workspace table.
For more information about this constraint, see the Constraints Guide in the online document collection.
See Also

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