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Eagle Schematic Editor

NOTE: I now recommend KiCAD over Eagle:
https://www.aeronetworks.ca/2020/02/kicad-schematic-and-pcb-design.html

-ooOoo-

I've been using Cadsoft Eagle for the schematics of little projects (Some not so little - 8 layers!) since about 2002, but since I don't use it all the time, every day, I can never remember the main editing commands, which makes each and every new project an exercise in frustration for a few minutes, until I figured out how to get started again.

One of the funniest things of Eagle, is the Stop button - it took me a long time to discover its usefulness.  The Stop button terminates the sometimes annoying auto repeat feature of Eagle.

Lately, I'm working on a Mac, which adds another wrinkle to it.  Eagle on a Mac is almost impossible to use without a 3-button mouse, so get a proper Bluetooth mouse and save yourself from a major head-ache.

Here are some of my notes - really for my own reference, but maybe someone else finds them helpful too.

Projects

Eagle will crash if you try to create a project where it doesn't have permissions.  So be sure to open a project under something like Projects, Eagle, eagle, MyUserName

Part Libraries

The included part and footprint libraries are mostly useless.  You got to make your own parts for almost everything.  However, you could get Eagle libraries with many useful hobby parts from Sparkfun.

Here is a Sparkfun tutorial to make a new part, that I am forever going back to: https://www.sparkfun.com/tutorials/110

Here is one about sensible design rules: https://www.sparkfun.com/tutorials/115

Schematic frame

Click Components, then search for Frame or Letter and place it at the origin marker.  Now you can place components inside the frame and describe the project in the title block.

Moving things in Eagle

To me, the most difficult thing to do is to move parts or footprints in the parts editor:

  • Click Group, click drag to draw a group over the parts and lines.
  • Click Move, then use Right Click (Ctrl Click on Mac, then click Move:Group) to pick up and move then Right Click (Click onMac) to drop.  
It will need practise whichever way you do it, but it works if you (accidentally) happen to do it right - bah, humbug...

Place and Rotate

First place the component, then Right Click (Ctrl-Click on a Mac) on the component to get a long menu that includes a Rotate command

Hidden Power Pins

Logic ICs and dual Op-Amps may have invisible power pins, which may automagically get connected to the wrong power rails.  Hiding pins is one of the dumbest ideas ever - whoever thought of that deserves seven lashes with a wet noodle.

Right Click, Invoke (Ctrl Click, Invoke on a Mac) to get a selection box for the invisible pins.
You can then attach them to one of the instances of the part.

Installing Eagle on Linux

Eagle is a 32 bit application, so before running the ./eagle-lin-6.4.0.run script, you got to do some tricks:
# yum install openssl-libs-1.0.1e-38.fc20.i686 openssl-libs-1.0.1e-38.fc20.x86_64 openssl-devel-1.0.1e-38.fc20.i686 openssl-devel-1.0.1e-38.fc20.x86_64 -y
# cd /usr/lib
# ln -s /usr/lib/libssl.so libssl.so.1.0.0
# ln -s /usr/lib/libcrypto.so libcrypto.so.1.0.0

and finally to give eagle a place to play in:
$ mkdir ~/eagle

Now Eagle should install and run:
$ /opt/eagle-6.4.0/bin/eagle

For pointy clicky access, make a desktop launcher for that.

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