The Cell Editor Instructions

  1. Make a list of the gates that you want to support with your cell library.
  2. Make a sketch of each gate, and determine exactly how you want it to look.  Keep in mind the number of inputs, number of outputs, the position of each input wire, and the position of each output wire.  Keep in mind that you cannot use generic and and or gates.  Each gate must have a fixed number of inputs and outputs.  Thus, a two-input and is different from a three-input and.   Also keep in mind things like positioning of the gate name when the gate is drawn, whether you want the gate-type to appear as part of the drawing, and where the gate-type will appear.  In some gates, such as flip-flops, it is necessary to have internal labels on each wire.  Make sure you make the drawing of the gate large enough to encompass all required elements.
  3. Decide whether your library will provide special effects, such as shading or 3D effects, for the gate drawings.
  4. Using a third-party drawing tool, create a drawing of each gate.  There are several good drawing tools available, among these are Micrografx Windows Draw, Micrografx Designer, Corel Draw, and Adobe Illustrator.  Do not use a bit-map editor such as the windows Paint program, and do not use bitmaps as part of your drawing. Make the drawings consistent with respect to size, special effects, and so forth.  Make sure there is plenty of room for input and output ports.  (Note, bitmaps will display correctly as long as the gate is not rotated.)
  5. Save each drawing as a windows metafile with the .wmf extension.  If you have the option of using extended metafiles, do not use this option.  If only a single type of metafile can be created by your tool, then that is the correct option to use.
  6. Once all .wmf files have been created, place them in a common directory where you will create your cell library.
  7. Start the Cell Editor, and select the New command from the File menu. (Or toolbar.)
  8. Select the New Cell command from the Edit menu. (Or toolbar.) This command will prompt you for the name of a .wmf file.  Select the first file and click OK.
  9. Select the Input Port command from the Mode menu. Click on the drawing where you want the ports to appear.  One click produces one port.  Input ports are magenta in color.
  10. Select the Output Port command from the Mode menu.   Click on the drawing where you want the output ports to appear. Again, one click produces one port.  Output ports are blue-green in color.
  11. If you want to specify the position of the gate name, select the Draw Label command from the Mode menu.  Click where you want the upper left corner of the gate name to appear.  If you click again, it will change the position of the gate name.
  12. If you want the gate type to appear in drawings of the gate, select the Draw Type command from the Mode menu, and proceed exactly as you did with the gate name.
  13. Select the Select command from the Mode menu, and move things around until the arrangement pleases you.
  14. Type in the name of your cell in the Name box.
  15. If you will be using FHDL translation, type in the FHDL name of your cell in the FHDL Name box.
  16. Save your library by selecting the Save command from the File menu.
  17. Repeat steps 8 through 16 for each additional cell.
  18. Save your library.
  19. You may make additional changes later by using the Open command on the File menu.
This page is Copyright (C) 1999, Peter M. Maurer
EMail: Peter_Maurer@Baylor.edu
Web Site: http://cs.baylor.edu/~maurer