GEDA Symbol Creation Guide

Creating symbols in GEDA can be a real headache without the use of a few tools. The following packages can be used to provide an efficient method for creating symbols.

Required Packages

• tragesym
• openoffice

Tragesym is a handy utility created to aid in symbol creation by using text files for describing the component. This information is taken by the program and an official GEDA symbol is created. Many times the symbol will require small changes to get exactly what you want; but for the most part, the changes should be minimal. In order to maintain a standard, I created a template file that will be used with each symbol. Create the file below and save as tragesym.tem

tragesym.tem

[options]
wordswap=yes
rotate_labels=no
sort_labels=yes
sym_width=1400
pinwidthvertical=400
pinwidthhorizontal=400

[geda_attr]
author=Your Name and e-mail address
documentation=http://www.xxx.com
version=20061020
name=test
device=test
refdes=U$
footprint=
description=bogus test symbol
numslots=0

[pins]
# tabseparated list of pin descriptions
# pinnr is the physical number of the pin
# seq is the pinseq= attribute, leave it blank if it doesn't matter
# type can be (in, out, io, oc, oe, pas, tp, tri, clk, pwr)
# style can be (line,dot,clk,dotclk,none). none if only want to add a net
# posit. can be (l,r,t,b) or empty for nets
# net specifies the name of the Vcc or GND name
# label represents the pinlabel.
# negation lines can be added with _Q_
# if you want to add a "_" or "\" use "\_" and "\\" as escape sequences
#-----------------------------------------------------
#pinnr	seq	type	style	posit.	net	label
#----------------------------------------------------- 

OpenOffice is used to create a tab-separated file for use with tragesym. This file will contain the following columns:

1. pinnr - the pin number of the device
2. seq - the sequence number of the pin (I think this is the order the pins are displayed on the symbol)
3. type - the type of pin {in, out, io, oc, oe, pas, tp, tri, clk, pwr}
4. style - the pin's style {line,dot,clk,dotclk,none}
5. posit. - this is the position of the pin on the symbol {l,r,t,b} left, right, top, bottom
6. net - nets are used for pwr pins along with style=none to create invisible pwr,gnd nets
7. label - the name of the pin

run oocalc2 to create the spreadsheet. The following illustrations provide an example:

Enter the necessary information and save a copy of the spreadsheet in the open document format (.ods). This might be needed later if changes are required. Now save another copy with the comma separated value (.csv) extension.

A warning will pop up; just ignore this by clicking yes.

Select the Field Delimiter as {Tab} and clear the text delimiter box.

Now create the tragesym file by performing the following operations:

• execute cp tragesym.tem filename.tra
• execute cat filename.csv >> filename.tra

These two commands should concatenate the template file and the csv file. Inspect the file and verify that the columns look properly aligned; if not the manually align them. The final step is to use tragesym to create the symbol.

• execute tragesym filename.tra filename.sym

Now that the symbol has been created, open the symbol for inspection and make the necessary changes.

• execute gschem filename.sym

This completes the symbol creation guide. To verify your symbol use the following:

• execute gsymcheck filename.sym

Last modified: Sun Mar 4 15:49:06 AST 2007