CadsoftUSA Eagle CAD new user notes

Think pick action, apply to item rather than select an item, then an action. Give up hope of a right click "pop-up" menu.

Move clicks on (to pick up the item) and off (to drop the item at the new location) with the left button. The right button changes direction when an item is picked up and selects a group otherwise.

Group selects multiple objects.

Smash ungroups.

Copy instantly makes a copy which you are now moving

Cut doesn't remove the item, but instead copies it to the clipboard (or "paste buffer")

Show highlightes

Library

• First make a symbol, then a package, THEN a device. See... devices can come in more than one package but still use the same symbol...
• Symbol
  • Copy (no... its called Cut) an existing symbol and Paste (yes... its called Paste) it in to the new one.
  • Move, Copy, Draw, etc.. to make the new symbol
  • Lable the pins with the Name command.

• Package
• Device
  • Pic the Package and Label
  • Add a Symbol
  • Connect the Lables (no... Names) on the Symbol to the Pins on the Package

Board layout.

• Good luck cramming it all in to the board size they allow.

Message: 4

Date: Wed, 23 Nov 2005 01:15:22 -0600

Mike Young [ mikewhy sbcglobal,n3t ]

Copper pours with Eagle:

After messing a bit with ground planes, isolation etches, and copper pours with Eagle Lite 4.15, here's a quick how-to:

POLYGON defines the outline of a copper pour. Drawn on a signal layer, 1-TOP or 16-BOTTOM, they can be given a signal name. This signal is then associated with the pour. The most reasonable signal for a ground plane is GND. Other signals are separated from the pour by a specified ISOLATION distance.

The "trick" to doing this is to first ripup the traces on the layer with the pour. I tried this (in vain, frustratingly) first on a board that was already routed, thinking it should carve the bottom traces into the new pour. This apparently doesn't work. Many long minutes were spent this way; it felt like hours, weeks. I even gave in and read the manual. A root canal would have been more fun. And then tossing caution to the wind (not really; the file was backed up safely), I ripped up the bottom traces and gave it a clean slate to work with. The simplest way to do this is to turn off all other signal layers and ripup all the signals. (Semi-colon does this nicely, automatically.)

Draw the polygon outline with a reasonable width; I used 16 mil, wide enough to see easily, and narrow enough to select easily. This is only the outline; Eagle fills in the closed shape. (Later, of course, so you wouldn't know what to expect...)

Set the ISOLATION distance in the toolbar, or use CHANGE ISOLATION later. I used 16 mil. If you're milling this, maybe use the end mill diameter. The default distance is 0, not very useful for a ground plane.

Draw a box around the dimension extents. Polygon segments must not overlap or cross each other. I even got Eagle to crash completely more than once by screwing this up. The best way to do this is to trace three sides of the bounding box, and sorta click twice on the fourth corner, but not quite double click. You just want to click the same point twice without moving the cursor. Eagle closes the outline back to the starting point, drawing the fourth side.

Now run the auto-router. I didn't try routing manually, so I don't know if that works. I expect it should. The POLYGON is calculated by RATSNEST or by AUTO. It stays an outline until either command is run. After it runs, the pads and vias are isolated, and new traces are properly isolated. Existing traces are apparently not examined by RATSNEST; they remain untouched and unisolated.

Ground pads are connect to the ground plane through thermals, a very nice touch. Thermals are small traces through the isolation space around the pad, connecting it electrically but isolating it thermally so it can be soldered.

I think you can specify how many and how wide in the design rules; I always wondered where that was used. Now I know. :) And now you know. Have fun. It really cleans up the ground traces nicely.

So, now I have a nice ground plane and isolated traces on my bottom side.

Alas, all is not perfectly well. These unplated through-holes really suck. I got clever and stuck SMT on the top, and through hole parts on the bottom, so everything could be soldered from just on top. The only headache was manually inserting a via where Eagle's autorouter would want to just use the component lead for a via. Some things, like RJ45 jacks, just can't be soldered from underneath. It wouldn't be so bad if Eagle didn't think itself smarter than you. You can't manually route a completely routed signal. I think it picks eligible signals from its ratsnest list. On a completely routed board, the list is empty. So you can't manually route a completely routed signal, and you can't ripup a thermal. I had to ripup the entire GND and reroute it all. It's not as bad as it might sound. You just have to know to do so. Autoroute restored it well enough that I can't see any difference, except for the one via and trace I added so it can be soldered from on top.)

Archive:

• List post "Persistent bug in Eagle's Library Editor(swapped labels forcomponent value on/off)" +
• PICList post "First stab at an Eagle library" +

See also:

• http://www.embedinc.com/pic/dload.htm Olin Lathrop's Eagle Libraries for PIC and other embedded work.+

Comments:

• brandnjTakeThisOuT at auburn.edu

  I agree with takethis....
  
  I had no real trouble with the pours once I routed the entire board.
  
  This was the first board I have done.....So I am not really sure what I am talking about.
  
  My pours are on the top layer...
  
  Are you making an entire layer a ground plane and then connecting your ground pads through vias/thermals...what is the difference b/t the two....

• kilocyclesTakeThisOuT at yahoo.com

  I do the pour(polygon gnd) command after my board is completely routed...auto, manual or a combination of both sometimes. That works well for me.
  Ted B.

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