Next: Editing symbols, Up: Symbols [Contents][Index]
This section has been written by Ales Hvezda for the gEDA project and later adapted for Lepton.
• Symbol example |
This document describes the creation of component symbols, including style conventions, and hints/tips and things to look out for when drawing symbols for the gEDA/gaf system.
Component symbols (from here on known as symbols) are drawn
using lepton-schematic
. You can start with a blank page or a known-to-be
good symbol that is similar to the one you want to create.
Before you open lepton-schematic
to create your symbol, there are a few
questions you should ask yourself, that will effect how you create
your symbol:
Once you’ve answered those questions, the following guide will be more useful to you.
To start building your symbol:
lepton-schematic
.
Use the ‘line’, ‘box’, ‘circle’, and ‘arc’ tools
(in the ‘Add’ menu) to create a simplified visual representation
of your device. Make sure that the only color you use is
graphic
(green). Do not place any pins on the device until the
next step.
To check what color you are using to draw, go to Edit → Color... (or hit E O).
If you have decided your symbol is graphical in nature (e.g., does not connect to anything, is just artwork), you can skip this step.
Add your first pin.
In the Edit dialog for a pin, you should see four attributes (name=value pairs) already associated with your new pin. These attributes can be edited by clicking on the attribute in the list at the top of the edit window, then clicking on the field you want to edit. Note that when selected, the ‘Add Attribute’ section of this dialog does not reflect what has been selected, as it is only meant for addition, not for editing.
Let’s look at each attribute already associated with your pin, and edit some of the values. I recommend expanding the size of the edit window until all attributes are visible.
lepton-netlist
, and
other tools. For our first pin, start this sequence number at
1
, incrementing it on each new pin, as we add them.
E
or
C
).
Possible pintype values are: in, out, io, oc, oe, pas, tp, tri, clk, pwr. See pintype attribute for more info.
Next: Editing symbols, Up: Symbols [Contents][Index]