Constraints Editor
Initializing Distributed RAM/ROM
You can use the Distributed RAM/ROM Initialization dialog box to initialize distributed RAM or distributed ROM. This sets the initial value of the selected memory locations.
Use the INIT constraint sparingly. Initialization should be handled as part of the HDL code whenever possible.
To Initialize Distributed RAM or ROM
  1.  Open the Distributed RAM/ROM Initialization dialog box.
  2.  Use the Ram/ROM Type list to select the memory type (RAM/ROM or Wide RAM ROM).
  3.  To limit instances listed in the RAM/ROM Instance list, enter a filter string in the Filter box and click Find. For example, to list only distributed ROM containing the string "init," type *init* in the Filter box. The filter is not case sensitive.
  4.  From the RAM/ROM Instance list, select the distributed ROM to initialize.
  5.  In the Comment box, enter a comment for this initialization entry.
  6.  Enter a starting and ending address for the initialization.
  7.  In the INIT String box, enter the initial value for the selected ROM.
Initializing distributed RAM/ROM creates an INIT constraint. 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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