Opening an Existing Design File

To open an existing design file while you are in the FPGA Editor window follow these steps.

1. Select File Open or click on the Open toolbar button.
   
   
   
   The Open dialog box appears, as shown in the “Open Dialog Box” figure of the “Menu Commands” chapter.
   
   
2. Select the Design option.
   
   
3. Enter the name of the .ncd file you want to open in the Design File field, or use the browse button to specify the design file name and directory.
   
   
4. Optionally, enter a constraints file name in the Physical Constraints File field, or click the browse button to specify the constraints file name and directory.
   
   If you do not enter a file name in the Constraints File field, the FPGA Editor looks for a constraints file with the same name as the .ncd file but with a.pcf extension.
   
   
5. Select an Edit Mode for the design from the pull-down list box.
   
   Select Read Only, No Logic Changes, or Read Write. The default is No Logic Changes. To always edit an existing design file in Read Write Mode, enter the following command in the fpga_editor.ini or fpga_editor_user.ini initialization files.
   
   setattr main edit-mode read-write
   
   
6. Click OK.
   
   The design file you specified is loaded in the FPGA Editor window.