EEC 116 - Magic tips

• Never use global labels (labels ending in "!"). Even in subcells as they can confuse your simulation.
• Use "Vdd" and "Gnd" for your power and ground nodes so they will be recognized by irsim.
• Put small stub extensions or overlays of the appropriate matching material in your upper-level cells for all interfacing signals and place labels on these small patches of material; otherwise these top-level labels will not be connected to the nodes in the lower-level cells during irsim simulation. For example, if a subcell has a piece of metal2 that comes to its edge and it used for "clock", you must place a small extension of metal2 with the label "clock" (or something different if you prefer) in an upper-level cell that uses this subcell. The small extension can be either next to or on top of the node in the lower-level cell.
• Error: "Cannot read extract file subcell.mag.ext"
  When placing subcells with the 'getcell <subcell>' command, do not use the ".mag" extension on the subcell as in, 'getcell <subcell.mag>' even though magic will let you. There will likely be ext2sim or irsim problems if you do.
• Error: "Did you point to the correct window?"
  If you get this message and you are over the layout window, try moving the window around a little.
• If magic does not re-extract cells even though you make changes, you may need to type 'extract all' to force magic to re-extract the root cell and all subcells.
• With the newest version of magic, the colon (:) is no longer used when entering commands into the text entry window but it can be used to focus on the text entry window when the layout window is active.
• You will probably save time by using the wiring tool. To use it:
• Press the spacebar once to select the wiring tool.
• Click the left mouse button while over a material to route with the material selected using the width selected.
• Move the mouse and click the left mouse button to create a new wire segment.
• Create a wire segment over a second material and then click the center mouse button to make a contact between the two materials.
• Press the spacebar three times to return to the box tool.
• When using cell instances, make sure that you use
  :getcell <cell>
  not
  :getcell <cell.mag>
  to prevent extraction problems.
• Make sure at every level of cell hierarchy that you label your ports/terminals and paint some metal. Otherwise your labels won't label anything. Use :getnode to check if your nodes are properly labeled.
• Use the :see command to allow you to see only the layers you care about.
• Finding Cell Area
• Press i to select the entire cell.
• Type the command 'box' to get the size in microns and lambdas.
• Remember, 1 λ = 0.09 µm, therefore the size = X * 0.09 um * Y * 0.09 um.
• Monitor the web page debugging and general info on Magic for the latest magic tips.

2009/05/27  Initial version
2010/02/09  Updated with some common errors
2010/10/19  Touched up and incorporated tips from debug.html