refdes_renum: warn of possible number clash with non-conforming values
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15 <h1 class="sectionedit568"><a name="about_pcb_layout_and_routing" id="about_pcb_layout_and_routing">About PCB layout and routing</a></h1>
16 <div class="level1">
18 <p>
19 This section answers general questions about PCB technology. If you&#039;re just beginning to learn about electronics, you might benefit from some of the answers given here.
20 </p>
22 </div>
23 <!-- EDIT568 SECTION "About PCB layout and routing" [1-214] -->
24 <h2 class="sectionedit569"><a name="what_s_a_footprint_what_s_a_via_what_s_a_track" id="what_s_a_footprint_what_s_a_via_what_s_a_track">What&#039;s a footprint? What&#039;s a via? What&#039;s a track?</a></h2>
25 <div class="level2">
27 <p>
28 You can find a glossary of terms <a href="http://geda.seul.org/wiki/geda:glossary" class="urlextern" title="http://geda.seul.org/wiki/geda:glossary" rel="nofollow">here</a>.
29 </p>
31 </div>
32 <!-- EDIT569 SECTION "What's a footprint? What's a via? What's a track?" [215-360] -->
33 <h1 class="sectionedit570"><a name="pcb_tools" id="pcb_tools">PCB Tools</a></h1>
34 <div class="level1">
36 <p>
37 This section provides answers about the open-source layout tool “PCB” itself.
38 </p>
40 </div>
41 <!-- EDIT570 SECTION "PCB Tools" [361-467] -->
42 <h2 class="sectionedit571"><a name="where_can_i_read_about_the_basics_of_using_pcb" id="where_can_i_read_about_the_basics_of_using_pcb">Where can I read about the basics of using pcb?</a></h2>
43 <div class="level2">
45 <p>
46 The pcb manual contains a concise description of the user interface in the section <a href="http://pcb.gpleda.org/pcb-cvs/pcb.html#Getting%20Started" class="urlextern" title="http://pcb.gpleda.org/pcb-cvs/pcb.html#Getting%20Started" rel="nofollow">“Getting Started”</a>.
47 </p>
49 </div>
50 <!-- EDIT571 SECTION "Where can I read about the basics of using pcb?" [468-695] -->
51 <h2 class="sectionedit572"><a name="is_there_a_way_to_save_the_file_as_an_older_version" id="is_there_a_way_to_save_the_file_as_an_older_version">Is there a way to save the file as an older version?</a></h2>
52 <div class="level2">
54 <p>
55 As new features are added to the file format, older versions of pcb might choke on portions of the layout using the bright new features. To prevent this kind of misbehavior, the pcb file contains a note on the minimum version string for the binary. Older versions of pcb refuse to load a layout saved by a newer pcb binary. This was the case for the addition of holes in polygons in 2010. You need a pcb that was compiled from source later than june 2010 to open these layouts.
56 </p>
58 <p>
59 Unfortunately, there is no way to save the layout in a way that allows older versions of pcb to read the file. However, if don&#039;t use the holes in polygon features, you can just hand-edit the file version header back to 20070407 and open the file with the older pcb binary.
60 </p>
62 </div>
63 <!-- EDIT572 SECTION "Is there a way to save the file as an older version?" [696-1514] -->
64 <h2 class="sectionedit573"><a name="i_found_a_bug_what_can_i_do_about_it" id="i_found_a_bug_what_can_i_do_about_it">I found a bug! What can I do about it?</a></h2>
65 <div class="level2">
66 <ol>
67 <li class="level1"><div class="li"> Start by reading <a href="http://pcb.gpleda.org/bugs.html" class="urlextern" title="http://pcb.gpleda.org/bugs.html" rel="nofollow">the pcb bug reporting page</a>.</div>
68 </li>
69 <li class="level1"><div class="li"> Check, what it needs to reproduce the bug.</div>
70 </li>
71 <li class="level1"><div class="li"> Ask on the <a href="http://www.geda.seul.org/mailinglist/index.html" class="urlextern" title="http://www.geda.seul.org/mailinglist/index.html" rel="nofollow">geda-user mailing</a> list if there is a work around, or has been dealt with in the bleading edge version of pcb. Note that you must subscribe to the geda-user e-mail list before you can post to this list.</div>
72 </li>
73 <li class="level1"><div class="li"> Check, wether the issue is already in the <a href="http://sourceforge.net/tracker/?group_id=73743&amp;atid=538811" class="urlextern" title="http://sourceforge.net/tracker/?group_id=73743&amp;atid=538811" rel="nofollow">bug tracking system of pcb</a>. If not, file a bug report. Make sure to give every information necessary to reproduce the bug and add the version of pcb that contains the bug.</div>
74 </li>
75 <li class="level1"><div class="li"> Finally, as with all open source projects, you may flex your programming muscles and try to squish the bug yourself. Please file a patch of the changes you had to make to the <a href="http://sourceforge.net/tracker/?group_id=73743&amp;atid=538811" class="urlextern" title="http://sourceforge.net/tracker/?group_id=73743&amp;atid=538811" rel="nofollow">BTS of pcb</a>. The patch will be gladly accepted to improve the next release of pcb.</div>
76 </li>
77 </ol>
79 </div>
80 <!-- EDIT573 SECTION "I found a bug! What can I do about it?" [1515-2572] -->
81 <h2 class="sectionedit574"><a name="how_can_i_set_the_manufacturing_rules_to_use_ie_drill_diameters_trace_width_space_specs" id="how_can_i_set_the_manufacturing_rules_to_use_ie_drill_diameters_trace_width_space_specs">How can I set the manufacturing rules to use (i.e. drill diameters, trace width/space specs)?</a></h2>
82 <div class="level2">
84 <p>
85 This topic is covered <a href="http://pcb.gpleda.org/pcb-cvs/pcb.html#Vendor-drill-mapping" class="urlextern" title="http://pcb.gpleda.org/pcb-cvs/pcb.html#Vendor-drill-mapping" rel="nofollow">in the manual</a>.
86 </p>
88 </div>
89 <!-- EDIT574 SECTION "How can I set the manufacturing rules to use (i.e. drill diameters, trace width/space specs)?" [2573-2780] -->
90 <h1 class="sectionedit575"><a name="non-obvious_aspects_of_the_gui" id="non-obvious_aspects_of_the_gui">Non-obvious aspects of the GUI</a></h1>
91 <div class="level1">
93 </div>
94 <!-- EDIT575 SECTION "Non-obvious aspects of the GUI" [2781-2826] -->
95 <h2 class="sectionedit576"><a name="auto-pan_bugs_me_what_can_i_do_about_it" id="auto-pan_bugs_me_what_can_i_do_about_it">Auto-pan bugs me. What can I do about it?</a></h2>
96 <div class="level2">
97 <ul>
98 <li class="level1"><div class="li"> You can tell, whether the screen will auto-pan by looking for little squares at the end of the cross hair cursor.</div>
99 </li>
100 <li class="level1"><div class="li"> Auto-pan can be toggled during move with a right mouse button click.</div>
101 </li>
102 <li class="level1"><div class="li"> Auto-pan speed can be set in <code>$HOME/.pcb/preferences</code> </div>
103 </li>
104 </ul>
106 </div>
107 <!-- EDIT576 SECTION "Auto-pan bugs me. What can I do about it?" [2827-3134] -->
108 <h2 class="sectionedit577"><a name="the_delete_key_sometimes_refuses_to_delete" id="the_delete_key_sometimes_refuses_to_delete">The delete key sometimes refuses to delete</a></h2>
109 <div class="level2">
112 Probably you try to delete a selected object. In pcb the delete button does not act on the selection, but on the object currently under the mouse. Consequently nothing will be deleted if an object is selected and the mouse hovers at some other place. Bottom line: Just position the mouse over an object and press the delete button. No need to select the object.
113 </p>
116 However, the Select menu contains an action that lets you delete the current selection. Currently, there is no accel key attached to this action.
117 </p>
120 Note, for versions younger than summer 2007 this issue is resolved. The delete key acts on selected objects too.
121 </p>
123 </div>
124 <!-- EDIT577 SECTION "The delete key sometimes refuses to delete" [3135-3815] -->
125 <h2 class="sectionedit578"><a name="i_try_to_move_an_object_but_pcb_won_t_let_me" id="i_try_to_move_an_object_but_pcb_won_t_let_me">I try to move an object, but pcb won&#039;t let me!</a></h2>
126 <div class="level2">
129 Most probably the object is locked. Locked objects won&#039;t highlight. To see, whether it indeed is, select-all-connected-objects from the select menu. Locked footprints are shown with a little L at their diamond shaped insertion mark. Use the lock tool to unlock the object in question. Note, that the lock tool always toggles the lock state of the object you click at. Afterward, an object report pops up that contains the lock state in the last line.
130 </p>
133 If you want to remove all locks, you may consider to remove all instances of the string <code>lock</code> in the *.pcb file with your favorite ascii editor.
134 </p>
137 A different reason for numb objects is “Only Names” in the settings menu. When checked, the selection tool will exclusively act on text. This is useful with crammed layouts. There is a complementary setting “Lock Names”, too.
138 </p>
140 </div>
141 <!-- EDIT578 SECTION "I try to move an object, but pcb won't let me!" [3816-4706] -->
142 <h1 class="sectionedit579"><a name="footprint_issues" id="footprint_issues">Footprint issues</a></h1>
143 <div class="level1">
145 </div>
146 <!-- EDIT579 SECTION "Footprint issues" [4707-4738] -->
147 <h2 class="sectionedit580"><a name="how_do_pcb_s_footprints_work" id="how_do_pcb_s_footprints_work">How do PCB&#039;s footprints work?</a></h2>
148 <div class="level2">
151 PCB supports two entirely separate footprint library mechanisms:
152 </p>
153 <ol>
154 <li class="level1"><div class="li"> The first is referred to as the “oldlib”, “pcblib”, or the “M4 library”. This system uses the macro language M4 to generate footprints on the fly. The M4 library is fairly large. A powerful feature of the m4 library is that an entire family of footprints can quickly be defined by defining an appropriate base macro. Several standard families of footprints exist in pcblib. Starting with the pcb-20070208 snapshot, the entire m4 library is available as “newlib” footprints (see the following paragraph) under the name “pcblib-newlib”.</div>
155 </li>
156 <li class="level1"><div class="li"> The second footprint library for PCB is called the “newlib”. Newlib footprints are defined using <acronym title="American Standard Code for Information Interchange">ASCII</acronym> text files which call out each graphical primitive which makes up an entire footprint. Newlib footprints can either be created graphically using PCB or via any other method which can produce a text file (text editor, awk/perl/ruby script, etc.). The use of a scripting or programming language is especially powerful because you can generate large footprints or families of footprints.</div>
157 </li>
158 </ol>
162 Therefore, during layout, you can use footprints which are distributed with PCB, you can find footprints via a web search, or you can create your own, and put them in a dedicated directory. The <a href="http://pcb.sourceforge.net/manual.html" class="urlextern" title="http://pcb.sourceforge.net/manual.html" rel="nofollow">pcb manual</a> has complete and up to date documentation for the element file format. <a href="http://gedasymbols.org" class="urlextern" title="http://gedasymbols.org" rel="nofollow">Gedasymbols.org</a> has a number of user contributed footprints. A somewhat incomplete but useful tutorial is available on the web at: <a href="http://www.brorson.com/gEDA/" class="urlextern" title="http://www.brorson.com/gEDA/" rel="nofollow">http://www.brorson.com/gEDA/</a> (search for the term “newlib”).
163 </p>
165 </div>
166 <!-- EDIT580 SECTION "How do PCB's footprints work?" [4739-6443] -->
167 <h2 class="sectionedit581"><a name="where_can_i_get_pre-drawn_footprints_for_pcb" id="where_can_i_get_pre-drawn_footprints_for_pcb">Where can I get pre-drawn footprints for PCB?</a></h2>
168 <div class="level2">
171 Currently, the best place to get footprints (besides in the PCB distribution) is the <a href="http://www.gedasymbols.org" class="urlextern" title="http://www.gedasymbols.org" rel="nofollow">gEDA Symbols website</a>. <a href="http://www.luciani.org/geda/pcb/pcb-footprint-list.html" class="urlextern" title="http://www.luciani.org/geda/pcb/pcb-footprint-list.html" rel="nofollow">John Luciani&#039;s website</a> has a large number of footprints and tools. Also, Darrell Harmon provides a nice footprint generating script <a href="http://www.dlharmon.com/geda/footgen.html" class="urlextern" title="http://www.dlharmon.com/geda/footgen.html" rel="nofollow">on his website</a>. You are welcome to contribute to the project and share your footprints. Finally, you can ask on the geda-user list, and somebody might take pity on you and send you a symbol. Note that you must subscribe to the geda-user e-mail list before you can post an e-mail to the geda-user list.
172 </p>
174 </div>
175 <!-- EDIT581 SECTION "Where can I get pre-drawn footprints for PCB?" [6444-7182] -->
176 <h2 class="sectionedit582"><a name="i_want_to_use_pcb_to_do_layout_how_do_i_know_what_value_to_use_for_the_footprint_attribute" id="i_want_to_use_pcb_to_do_layout_how_do_i_know_what_value_to_use_for_the_footprint_attribute">I want to use PCB to do layout. How do I know what value to use for the footprint attribute?</a></h2>
177 <div class="level2">
180 This question is a common one amongst new gEDA users. Indeed, helping newbies determine the appropriate footprint names lies at the core of the ongoing <a href="geda-faq-gschem.html#what_s_this_business_about_heavy_vs._light_symbols" class="wikilink1" title="geda-faq-gschem.html">light vs. heavy symbol</a> debate. In the current, light symbol gEDA/gaf distribution, you need to attach the footprint attribute at the schematic level (i.e. using either gschem or gattrib). The name of the footprint to use depends upon whether you are using the newlib or the M4 library (pcblib).
181 </p>
183 </div>
184 <!-- EDIT582 SECTION "I want to use PCB to do layout. How do I know what value to use for the footprint attribute?" [7183-7806] -->
185 <h3 class="sectionedit583"><a name="newlib" id="newlib">Newlib</a></h3>
186 <div class="level3">
189 The newlib stores one footprint per file, and the footprint names used by the newlib are the file names of the footprint files.
190 </p>
193 There are several ways to determine the newlib footprint names to use:
194 </p>
195 <ul>
196 <li class="level1"><div class="li"> You can browse the available footprints by running pcb and opening the footprint library window (available from the menu bar via “Window → library”). Click on the “newlib” library group, and then select a sublibrary to browse its symbols. The name of each footprint appears in the “Elements” window on the right hand side of the footprint library browser. Use the name exactly as it appears in the browser for the footprint attribute in gschem or gattrib.</div>
197 </li>
198 <li class="level1"><div class="li"> The newlib footprints distributed with PCB are stored in the directories under <strong><code>${PREFIX}/share/pcb/newlib</code></strong>. (<strong><code>${PREFIX}</code></strong> is the install directory you specified when configuring/building PCB.) The name to stick in the “footprint” attribute is the filename of the footprint you wish to use.<br/>
199 For example, on my machine I installed gEDA with the prefix <strong><code>/usr/local/geda/</code></strong>. The 0805 package (for SMT resistors or caps) lives in a file with absolute path<br/>
200 <strong><code>/usr/local/geda/share/pcb/newlib/generic_SMD_packages/0805_reflow_solder</code></strong> <br/>
201 Therefore, to use this footprint on a component I set its “footprint” attribute to <strong><code>0805_reflow_solder</code></strong> using gschem or gattrib.<br/>
202 Note that if the newlib symbol you want to use lives in a non-standard directory, gsch2pcb needs you to specify a path to that directory, either within your project.rc file (if you use one) or using the <strong><code>–elements-dir</code></strong> flag (from the command line).</div>
203 </li>
204 <li class="level1"><div class="li"> Finally, since each new design typically requires you to draw at least a couple of new footprints, it’s likely you will have a local “footprints” directory. As previously, the footprint name to use is the filename you assign to each of your new footprints. Again, don’t forget to add a line to your project.rc file telling gsch2pcb where to find your local footprints. Alternately, you can run gsch2pcb with the <strong><code>–elements-dir</code></strong> flag set to point to your local footprint directory.</div>
205 </li>
206 </ul>
208 </div>
209 <!-- EDIT583 SECTION "Newlib" [7807-9961] -->
210 <h3 class="sectionedit584"><a name="m4_library" id="m4_library">M4 library</a></h3>
211 <div class="level3">
214 The M4 library stores the footprints as M4 macros; there are usually several (many) footprints contained in each footprint file. The different footprints in a single file are generally variations on a single pattern (e.g. DIP-8, DIP-14, DIP-16, etc.) The easiest way to find the correct footprint attribute name is by browsing through the “pcblib” library in the PCB library window. The footprint attribute is given in square brackets in the description. Also you can view the list of footprints from pcblib at the <a href="http://www.gedasymbols.org/footprints/" class="urlextern" title="http://www.gedasymbols.org/footprints/" rel="nofollow">gEDA Symbols webpage</a>.
215 </p>
218 The following m4 libraries have received more attention and improvements than the others:
219 </p>
220 <ul>
221 <li class="level1"><div class="li"> ~amp for Amp connectors</div>
222 </li>
223 <li class="level1"><div class="li"> ~amphenol for Amphenol connectors</div>
224 </li>
225 <li class="level1"><div class="li"> ~geda for many diverse parts used in basic design using gEDA (resistors, caps, etc).</div>
226 </li>
227 <li class="level1"><div class="li"> ~bourns for products like trim pots from Bourns</div>
228 </li>
229 <li class="level1"><div class="li"> ~cts for products like resistor packs from CTS</div>
230 </li>
231 <li class="level1"><div class="li"> ~johnstech for Johnstech sockets</div>
232 </li>
233 <li class="level1"><div class="li"> ~minicircuits for Minicircuits specific footprints</div>
234 </li>
235 <li class="level1"><div class="li"> ~panasonic for some Panasonic specific footprints</div>
236 </li>
237 </ul>
241 Finally, for both the newlib and the M4 lib, it is extremely important that you verify that the footprint name you use instantiates *exactly* the footprint you want when you place it in PCB. Therefore, it is critical to inspect the footprint before you use it. You can verify the footprint you want to use by clicking on it in the “footprint library” window, and then placing it onto an empty spot in PCB’s drawing area. Manually inspect the footprint to ensure that it has the correct number of pins/pads, correct dimensions, etc.
242 </p>
245 Also, once you generate Gerber files, make sure you <a href="geda-pcb_tips.html#i_m_done_with_my_layout._how_should_i_check_my_design" class="wikilink1" title="geda-pcb_tips.html">inspect all footprints instantiated in your Gerbers</a> using gerbv (or an equivalent Gerber viewer) before you send your design out for fabrication.
246 </p>
248 </div>
249 <!-- EDIT584 SECTION "M4 library" [9962-11871] -->
250 <h2 class="sectionedit585"><a name="what_is_the_recommended_way_to_deal_with_different_footprints_for_the_same_sort_of_device" id="what_is_the_recommended_way_to_deal_with_different_footprints_for_the_same_sort_of_device">What is the recommended way to deal with different footprints for the same sort of device?</a></h2>
251 <div class="level2">
254 For example, an opamp may be DIP8 or SO8. A resistor may be 0603, 0805, 1208, or through-hole. How do I know what package and footprint to use, and how do I manage the choices?
255 </p>
258 First off, the footprint you should use is a decision for you to make, not your CAD tool. It is up to you to choose your preferred package type/footprint, and then attach the correct footprint attribute to the component in the schematic. Once you have choosen which package (and footprint) you wish to use, then either <a href="geda-pcb_tips.html#where_can_i_get_pre-drawn_footprints_for_pcb" class="wikilink1" title="geda-pcb_tips.html">find an appropriate footprint</a>, or <a href="geda-pcb_tips.html#how_do_i_draw_a_new_footprint" class="wikilink1" title="geda-pcb_tips.html">draw one yourself</a> and save it in a local directory.
259 </p>
262 As far as managing the footprint choices (and indeed the large number of component attributes you are likely to have): Use <a href="geda-faq-attribs.html#help_my_design_has_hundreds_of_components_and_it_s_a_pain_to_use_gschem_to_attach_all_my_attributes" class="wikilink1" title="geda-faq-attribs.html">gattrib</a>. That’s what it’s for.
263 </p>
265 </div>
266 <!-- EDIT585 SECTION "What is the recommended way to deal with different footprints for the same sort of device?" [11872-12953] -->
267 <h2 class="sectionedit586"><a name="how_do_i_draw_a_new_footprint" id="how_do_i_draw_a_new_footprint">How do I draw a new footprint?</a></h2>
268 <div class="level2">
271 Everybody does this a little differently. Some people draw the footprint entirely using PCB. Some people first draw a preliminary footprint in PCB, and then finish it off by hand editing it (e.g. using emacs). Some people write <acronym title="Practical Extraction and Report Language">Perl</acronym> or Python scripts to autogenerate footprints.
273 </p>
274 <ul>
275 <li class="level1"><div class="li"> use a text editor. See <a href="http://www.brorson.com/gEDA/land_patterns_20070818.pdf" class="urlextern" title="http://www.brorson.com/gEDA/land_patterns_20070818.pdf" rel="nofollow"> the manual on footprint creation</a> by Stuart Brorson for the details.</div>
276 </li>
277 <li class="level1"><div class="li"> draw the part in PCB and save as a footprint. See the <a href="http://ronja.twibright.com/guidelines/footprints.php" class="urlextern" title="http://ronja.twibright.com/guidelines/footprints.php" rel="nofollow">howto by Karel Kulhavy</a></div>
278 </li>
279 <li class="level1"><div class="li"> or use a <a href="http://dlharmon.com/geda/footgen.html" class="urlextern" title="http://dlharmon.com/geda/footgen.html" rel="nofollow"> python script</a> by Darrel Harmon for “two pad”, “SOxx”, “tabbed” and QFP” style</div>
280 </li>
281 <li class="level1"><div class="li"> or use a <a href="http://www.brorson.com/gEDA" class="urlextern" title="http://www.brorson.com/gEDA" rel="nofollow"> perl script</a> by Stuart Brorson for two pad SMT components</div>
282 </li>
283 <li class="level1"><div class="li"> or use a <a href="http://www.luciani.org/geda/pcb/pcb-perl-library.html" class="urlextern" title="http://www.luciani.org/geda/pcb/pcb-perl-library.html" rel="nofollow">perl script</a> from John Luciani – can be adapted to DIL, SOxx-Style, QFP, or even circular arrangement of pads. </div>
284 </li>
285 <li class="level1"><div class="li"> or use the web based application <a href="http://www.gedasymbols.org/user/dj_delorie/tools/dilpad.html" class="urlextern" title="http://www.gedasymbols.org/user/dj_delorie/tools/dilpad.html" rel="nofollow">dilpad</a> written by DJ Delorie for “SOxx” style footprints.</div>
286 </li>
287 </ul>
289 </div>
290 <!-- EDIT586 SECTION "How do I draw a new footprint?" [12954-14152] -->
291 <h2 class="sectionedit587"><a name="how_do_i_edit_change_an_existing_footprint" id="how_do_i_edit_change_an_existing_footprint">How do I edit/change an existing footprint?</a></h2>
292 <div class="level2">
295 You can convert a footprint into an ordinary layout, edit the parts and convert them back to footprint. In the following list the parts in mono space font are actions from the buffer menu.
296 </p>
297 <ol>
298 <li class="level1"><div class="li"> Select element</div>
299 </li>
300 <li class="level1"><div class="li"> Copy selection to buffer ([ctrl-c]). </div>
301 </li>
302 <li class="level1"><div class="li"> <code>Break buffer into pieces</code>. Pins become vias and pads become tracks. Unfortunately, some information is lost during the process. Namely, the square flag names of pins and pads. You have to regenerate this information later.</div>
303 </li>
304 <li class="level1"><div class="li"> <code>Paste buffer to layout</code></div>
305 </li>
306 <li class="level1"><div class="li"> Do the desired changes. Note, that only vias, tracks and rectangles are allowed. No text, no arcs, no general polygons. </div>
307 </li>
308 <li class="level1"><div class="li"> Select all objects that belong to the footprint</div>
309 </li>
310 <li class="level1"><div class="li"> Copy selection to buffer ([ctrl-c]). The position of the crosshair will determine the origin of the resulting footprint.</div>
311 </li>
312 <li class="level1"><div class="li"> <code>Convert buffer to element</code>. This converts vias to pins. Tracks and rectangles get SMD pads. </div>
313 </li>
314 <li class="level1"><div class="li"> <code>Paste buffer to layout</code></div>
315 </li>
316 <li class="level1"><div class="li"> Place the mouse over the pads that got rounded during step 4 and press q. This squares off the rounded pad edges.</div>
317 </li>
318 <li class="level1"><div class="li"> Go over every pad, press [n] and give a name to the pad.</div>
319 </li>
320 <li class="level1"><div class="li"> Place the mouse somewhere where there is no pad or pin and give a name to the symbol.</div>
321 </li>
322 <li class="level1"><div class="li"> Move the name to the place where you want the refdes or the value to appear. </div>
323 </li>
324 <li class="level1"><div class="li"> Select everything and <code>copy selection to buffer</code></div>
325 </li>
326 <li class="level1"><div class="li"> <code>Save buffer as elements to file</code>. </div>
327 </li>
328 </ol>
331 Alternatively, you can use your favorite text editor and edit the source code of the footprint.
332 </p>
334 </div>
335 <!-- EDIT587 SECTION "How do I edit/change an existing footprint?" [14153-15697] -->
336 <h2 class="sectionedit588"><a name="pcb_does_not_save_silk_when_i_try_to_make_a_footprint" id="pcb_does_not_save_silk_when_i_try_to_make_a_footprint">pcb does not save silk when I try to make a footprint</a></h2>
337 <div class="level2">
340 The silk of footprints can only deal with lines and arcs. All the other objects like polygons, rectangles and text are silently omitted during <code>Convert buffer to element</code>. If you need text in footprints you have to literary draw the letters with the line tool.
341 </p>
343 </div>
344 <!-- EDIT588 SECTION "pcb does not save silk when I try to make a footprint" [15698-16027] -->
345 <h2 class="sectionedit589"><a name="what_is_the_proper_way_to_make_a_double-sided_footprint" id="what_is_the_proper_way_to_make_a_double-sided_footprint">What is the proper way to make a double-sided footprint?</a></h2>
346 <div class="level2">
349 You can use the “onsolder” flag to place pads on the opposite side of the
350 board. You would have something like this for a connector on both sides of the board:
351 </p>
354 <code>Pad[-40000 -7000 -40000 7000 2700 2400 3000 “B1” “B1” “square”]</code><br/>
356 <code>Pad[-40000 -7000 -40000 3000 2700 2400 3000 “A1” “A1” “square,onsolder”]</code>
357 </p>
360 If you draw the footprint with pcb-<acronym title="Graphical User Interface">GUI</acronym> and do convert-buffer-to-element, the lines on the second layer become pads with the onsolder flag. Yes, it is the second layer, regardless its name.
361 </p>
363 </div>
364 <!-- EDIT589 SECTION "What is the proper way to make a double-sided footprint?" [16028-16597] -->
365 <h2 class="sectionedit590"><a name="how_can_i_achieve_pads_without_paste" id="how_can_i_achieve_pads_without_paste">How can I achieve pads without paste?</a></h2>
366 <div class="level2">
369 Sometimes, exposed copper should not receive solder paste. A common example is the pads of an edge connector. This can be achieved with the <code>nopaste</code> <a href="geda-glossary.html#flag" class="wikilink1" title="geda-glossary.html">flag</a>. Currently, there is no <acronym title="Graphical User Interface">GUI</acronym> way to set the flag. Use a text editor to add this flag to the pads of a footprint.
371 </p>
373 </div>
374 <!-- EDIT590 SECTION "How can I achieve pads without paste?" [16598-16939] -->
375 <h2 class="sectionedit591"><a name="how_do_i_add_a_footprint_library_to_pcb" id="how_do_i_add_a_footprint_library_to_pcb">How do I add a footprint library to PCB?</a></h2>
376 <div class="level2">
379 Adding footprint libraries can be done from the <acronym title="Graphical User Interface">GUI</acronym>:<br/>
381 <strong><em>File</em></strong>&gt; <strong><em>Preferences</em></strong>&gt; <strong><em>Library</em></strong>&gt; <strong>FOOTPRINTDIRECTORY</strong><br/>
383 Alternatively you can edit the file <code>$HOME/.pcb/preferences</code>. Make sure, no instance of pcb is currently running. Look for the line that starts with “library-newlib”.
384 Don’t forget to include the new directory into either your gsch2pcbrc, or your local gafrc file (if you are using gsch2pcb, that is).
385 </p>
387 </div>
388 <!-- EDIT591 SECTION "How do I add a footprint library to PCB?" [16940-17445] -->
389 <h2 class="sectionedit592"><a name="how_do_i_update_a_footprint_in_my_layout" id="how_do_i_update_a_footprint_in_my_layout">How do I update a footprint in my layout?</a></h2>
390 <div class="level2">
393 There is no way to automatically replace all instances of a footprint with the new version, yet. But there is a special mode of the buffer-paste tool, that will reduce the amount of clicks for manual replacement.<br/>
395 Use the Window→Library dialog box to manually choose the new footprint. The tool becomes the buffer-paste tool, with the new footprint preloaded. Rotate it if needed with Buffer→Rotate Buffer. Position the new footprint over the old one, and shift-left-mouse-click to replace the old footprint with the new one. Watch out for being 180 degrees off, use &#039;o&#039; to check the rats nest after each placement, and undo if it appears you placed it backwards.
396 </p>
398 </div>
399 <!-- EDIT592 SECTION "How do I update a footprint in my layout?" [17446-18168] -->
400 <h2 class="sectionedit593"><a name="pcb_is_not_finding_my_footprints_why" id="pcb_is_not_finding_my_footprints_why">PCB is not finding my footprints. Why?</a></h2>
401 <div class="level2">
404 The footprint path that PCB uses is defined using the <strong><code>Pcb.elementPath</code></strong> variable in the app-defaults file named <strong><code>PCB</code></strong>. The path for the <strong><code>PCB</code></strong> file is set using the <strong><code>XAPPLRESDIR</code></strong> environment variable which is typically set from within the wrapper script named <strong><code>pcb</code></strong>.
405 </p>
407 </div>
408 <!-- EDIT593 SECTION "PCB is not finding my footprints. Why?" [18169-18517] -->
409 <h2 class="sectionedit594"><a name="now_that_i_have_all_of_these_footprints_where_do_i_put_them" id="now_that_i_have_all_of_these_footprints_where_do_i_put_them">Now that I have all of these footprints where do I put them?</a></h2>
410 <div class="level2">
413 I prefer to place all “production-ready” footprints in a single directory that is not in the gEDA/PCB install tree. When a new version of gEDA/PCB comes out I do not make any changes to project files or libraries. If there are newlib footprints in the PCB library that I want to use I copy them to the “production-ready” footprint directory.
414 </p>
417 Rather than change configuration files to get gsch2pcb to find the footprints I create a wrapper script called <strong><code>sch2pcb</code></strong> that contains the footprint path. All users use the same script and access the same production footprints.
418 </p>
421 To use the <strong><code>sch2pcb</code></strong> script that is listed below replace the string <strong><code>FOOTPRINT_DIR</code></strong> with your footprint directory:
423 </p>
424 <pre class="code">#!/bin/bash
425 gsch2pcb --elements-dir FOOTPRINT_DIR $@</pre>
428 Or another user&#039;s version:
430 </p>
431 <pre class="code">#!/bin/bash
432 #this script was written by John Luciani
433 gsch2pcb --elements-dir /home/user/pcb/footprints/user --use-files $@</pre>
436 Alternatively you can make use of a project file which gsch2pcb reads for its options. For example the file <code>myproject</code> could look like this:
438 </p>
439 <pre class="code">schematics myschematic.sch myschematic2.sch
440 elements-dir /myfootprintdir
441 output-name mypcb
442 skip-m4</pre>
445 The example file searches through <code>myfootprintdir</code> for footprints used in <code>myschematic.sch</code> and <code>myschematic2.sch</code> and creates <code>mypcb.pcb</code> skipping m4 style footprints. gsch2pcb is then called with the project file as an option.
447 </p>
448 <pre class="code">gsch2pcb myproject</pre>
450 </div>
451 <!-- EDIT594 SECTION "Now that I have all of these footprints where do I put them?" [18518-20066] -->
452 <h1 class="sectionedit595"><a name="component_placement" id="component_placement">Component placement</a></h1>
453 <div class="level1">
455 </div>
456 <!-- EDIT595 SECTION "Component placement" [20067-20101] -->
457 <h2 class="sectionedit596"><a name="how_do_i_rotate_a_selection_ie_of_more_than_one_item" id="how_do_i_rotate_a_selection_ie_of_more_than_one_item">How do I rotate a selection (i.e. of more than one item)?</a></h2>
458 <div class="level2">
459 <ol>
460 <li class="level1"><div class="li"> Select the items</div>
461 </li>
462 <li class="level1"><div class="li"> Buffer → Cut selection to buffer</div>
463 </li>
464 <li class="level1"><div class="li"> Buffer → Rotate buffer 90 deg CCW (or CW)</div>
465 </li>
466 <li class="level1"><div class="li"> Click anywhere on the board and the selection is pasted on the design again.</div>
467 </li>
468 </ol>
472 Note: Square pads may not clear polygons correctly. Rectangular pads are ok, though. This is a known issue caused by the difficulty to know the reference direction of a square pad.
473 </p>
475 </div>
476 <!-- EDIT596 SECTION "How do I rotate a selection (i.e. of more than one item)?" [20102-20545] -->
477 <h2 class="sectionedit597"><a name="how_do_i_rotate_objects_by_an_arbitrary_angle" id="how_do_i_rotate_objects_by_an_arbitrary_angle">How do I rotate objects by an arbitrary angle?</a></h2>
478 <div class="level2">
479 <ol>
480 <li class="level1"><div class="li"> Cut the object into the paste buffer.</div>
481 </li>
482 <li class="level1"><div class="li"> Type ”:FreeRotateBuffer(45)”. The colon will open the command line. Replace “45” with the angle you want to rotate by.</div>
483 </li>
484 <li class="level1"><div class="li"> Paste the object back to your board.</div>
485 </li>
486 </ol>
490 Note: For internal reasons, FreeRotateBuffer does not work with exact squares. As workaround use two or more polygons that add to give a square.
491 </p>
493 </div>
494 <!-- EDIT597 SECTION "How do I rotate objects by an arbitrary angle?" [20546-20958] -->
495 <h2 class="sectionedit598"><a name="how_do_i_move_objects_by_an_arbitrary_distance" id="how_do_i_move_objects_by_an_arbitrary_distance">How do I move objects by an arbitrary distance?</a></h2>
496 <div class="level2">
497 <ol>
498 <li class="level1"><div class="li"> Let the mouse hover over the object to be moved.</div>
499 </li>
500 <li class="level1"><div class="li"> Type ”:MoveObject(x,y,unit)”. The colon will open the command line. Replace “x” and “y” with the desired coordinates and “unit” with either “mm”, or “mil”.</div>
501 </li>
502 <li class="level1"><div class="li"> Type [return].</div>
503 </li>
504 </ol>
507 If both coordinates are prefixed with a ”+”, or ”-” the move is relative to the current position. Else the object is moved to absolute coordinates.
508 </p>
510 </div>
511 <!-- EDIT598 SECTION "How do I move objects by an arbitrary distance?" [20959-21400] -->
512 <h2 class="sectionedit599"><a name="how_do_i_move_objects_to_an_absolute_location" id="how_do_i_move_objects_to_an_absolute_location">How do I move objects to an absolute location?</a></h2>
513 <div class="level2">
516 Use the command “MoveObject()” as described above.
517 </p>
519 </div>
520 <!-- EDIT599 SECTION "How do I move objects to an absolute location?" [21401-21511] -->
521 <h2 class="sectionedit600"><a name="how_do_i_change_the_size_of_a_graphical_object_such_as_text_silkscreen_lines_etc" id="how_do_i_change_the_size_of_a_graphical_object_such_as_text_silkscreen_lines_etc">How do I change the size of a graphical object (such as text, silkscreen lines, etc)?</a></h2>
522 <div class="level2">
523 <ul>
524 <li class="level1"><div class="li"> Mouse over the object and hit [<strong><code>s</code></strong>]. This will increase the size of the object you are mousing over.</div>
525 </li>
526 <li class="level1"><div class="li"> Mouse over the object and hit [<strong><code>&lt;shift&gt;-S</code></strong>]. This will decrease the size of the object you are mousing over.</div>
527 </li>
528 </ul>
532 You can alter the increase/decrease quantum using the <strong><em>file</em></strong><strong><em>preferences</em></strong><strong><em>increments</em></strong> menu.
533 </p>
535 </div>
536 <!-- EDIT600 SECTION "How do I change the size of a graphical object (such as text, silkscreen lines, etc)?" [21512-21963] -->
537 <h2 class="sectionedit601"><a name="how_do_i_put_components_on_both_faces_in_pcb" id="how_do_i_put_components_on_both_faces_in_pcb">How do I put components on both faces in PCB?</a></h2>
538 <div class="level2">
541 There are two ways to do it:
542 </p>
543 <ul>
544 <li class="level1"><div class="li"> Pressing the tab key will alternate the active side between the component and solder sides. When you place components, they will go on the active side.</div>
545 </li>
546 <li class="level1"><div class="li"> If you are viewing one side of the board, place a component there and (with the cursor over it) press the [<strong><code>b</code></strong>] key (wich means, send the component to the Back side) the component go to the other side of the board.</div>
547 </li>
548 </ul>
550 </div>
551 <!-- EDIT601 SECTION "How do I put components on both faces in PCB?" [21964-22432] -->
552 <h2 class="sectionedit602"><a name="i_cant_t_move_the_components_on_the_other_side_of_the_board" id="i_cant_t_move_the_components_on_the_other_side_of_the_board">I cant&#039;t move the components on the other side of the board!</a></h2>
553 <div class="level2">
556 The mouse is only sensitive to components on the active side of the board. This prevents ampbiguities with components placed on both, top and bottom. By default, top side is active and the bottom side is the “far side” whose components are ignored by the mouse. You can swap the roles of the sides to make components on the far side accessible. The key-accels [tab], [shift-tab], [ctrl-tab] and <a href="ctrl-shift-tab_will_do_the_trick._these_accels_combine_the_swap_with_different_vertical_and_horizontal_flips._specifically-tab_-swap_sides_and_mirror_along_horizontal_axis._this_is_like_flipping_a_real_board_upside-down._shift-tab_-swap_sides_and_mirror_along_vertical_axis._this_mimics_flipping_a_real_board_like_a_page_in_a_book._ctrl-tab_-swap_sides_and_mirror_along_both_axis._that_is_do_an_inversion._this_cannot_be_done_with_a_real_board_..._ctrl-shift-tab_-no_mirroring_just_swap_front_side_and_far_side._this_is_like_an_x-ray_view._how_do_i_know_which_side_a_component_sits_on_if_the_component_is_on_the_currrently_far_side_of_the_layout_its_silk_layer_is_drawn_in_grey._if_unsure_deactivate_the_far_side_with_the_far_side_button_at_the_bottom_of_the_layer_button_row._this_should_remove_the_silk_of_all_far_side_components_from_the_view._how_do_i_define_a_silkscreen_layer_for_the_other_side_of_the_board_although_only_one_silk_layer_button_is_visible_in_the_gui_silkscreen_for_both_sides_is_automatically_configured._in_default_view_the_silk_layer_button_refers_to_silkscreen_on_the_component_side_of_the_board._to_place_text_or_lines_on_solder_silk_you_have_to_flip_the_board_with_the_tab_key_or_shift-tab_if_you_prefer_a_left-right_flip_._this_is_like_physically_turning_the_board_to_the_other_side._it_turns_the_solder_layer_on_top_and_component_layer_on_bottom._objects_on_component_silk_layer_will_be_greyed_out._if_you_draw_to_silk_lines_will_always_go_to_the_current_top_silk_layer_which_is_solder_now._the_same_happens_to_components_and_their_silk_screen._flip_the_board_again_to_return_to_default_view._why_text_i_add_to_the_solder_side_not_reversed_add_it_while_the_board_is_flipped_tab_._just_selecting_the_solder_side_is_insufficient._new_text_always_reads_correctly_from_the_side_you_re_looking_at._is_it_possible_to_use_an_arbitrary_grid_spacing_yes._you_can_use_the_command_nowiki_setvalue_grid_value_unit_nowiki_._to_do_this-type_-setvalue_grid_x_unit_._the_colon_will_open_the_command_line._replace_x_with_the_desired_grid_spacing_and_unit_with_either_mm_or_mil_._-_type_return_._how_do_i_set_the_origin_in_pcb_the_absolute_origin_is_always_in_the_upper_left_corner_of_the_accessible_area._this_cannot_be_set_to_some_other_place._however_coordinates_of_objects_can_also_be_given_relative_to_the_current_grid._in_the_gtk2_version_of_pcb_coordinates_are_shown_in_the_upper_right_corner_of_the_main_window._the_right_pair_is_the_absolute_position_while_the_left_pair_reflects_the_position_relative_to_an_arbitrary_marker._this_marker_is_set_to_the_current_position_of_the_mouse_by_the_key_sequence_ctrl-m_._you_may_want_to_set_the_marker_to_a_grid_point_or_a_specific_pin._how_do_i_measure_distances_and_dimensions_of_components_use_ctrl-m_to_set_the_origin_and_read_the_distance_of_the_mouse_pointer_relative_to_this_point_on_the_upper_left_of_the_pcb_window._some_objects_like_vias_and_tracks_yield_usefull_information_in_object_reports._access_the_report_of_the_object_currently_under_the_mouse_pointer_with_ctrl-r_._how_do_i_hide_rats_of_specific_nets_in_the_netlist_window_doubleclick_on_the_specific_rat_name_then_press_o_on_your_board_window._your_rats_are_hidden_for_that_net._in_the_netlist_window_an_asterisk_appears_in_from_of_the_rat_name._to_reverse-follow_the_same_procedure._routing_how_do_i_route_a_connection_from_solder_to_component_side_and_back_while_using_the_line_tool_use_the_number_keys_on_top_of_the_keyboard_to_switch_layers._a_via_will_be_placed_automatically_at_the_endpoint_of_the_last_complete_segment._how_do_i_change_the_routing_style_there_is_a_set_of_predefined_sizes_for_routing._the_sets_bear_suggestive_names_signal_power_fat_and_skinny_._hit_the_button_route_style_to_configure_the_sizes_of_the_current_set_to_your_needs._you_can_set_the_names_and_the_default_values_of_these_parameter_sets_in_a_config_file_.pcb_settings_for_the_glossary.html" class="wikilink2" title="ctrl-shift-tab_will_do_the_trick._these_accels_combine_the_swap_with_different_vertical_and_horizontal_flips._specifically-tab_-swap_sides_and_mirror_along_horizontal_axis._this_is_like_flipping_a_real_board_upside-down._shift-tab_-swap_sides_and_mirror_along_vertical_axis._this_mimics_flipping_a_real_board_like_a_page_in_a_book._ctrl-tab_-swap_sides_and_mirror_along_both_axis._that_is_do_an_inversion._this_cannot_be_done_with_a_real_board_..._ctrl-shift-tab_-no_mirroring_just_swap_front_side_and_far_side._this_is_like_an_x-ray_view._how_do_i_know_which_side_a_component_sits_on_if_the_component_is_on_the_currrently_far_side_of_the_layout_its_silk_layer_is_drawn_in_grey._if_unsure_deactivate_the_far_side_with_the_far_side_button_at_the_bottom_of_the_layer_button_row._this_should_remove_the_silk_of_all_far_side_components_from_the_view._how_do_i_define_a_silkscreen_layer_for_the_other_side_of_the_board_although_only_one_silk_layer_button_is_visible_in_the_gui_silkscreen_for_both_sides_is_automatically_configured._in_default_view_the_silk_layer_button_refers_to_silkscreen_on_the_component_side_of_the_board._to_place_text_or_lines_on_solder_silk_you_have_to_flip_the_board_with_the_tab_key_or_shift-tab_if_you_prefer_a_left-right_flip_._this_is_like_physically_turning_the_board_to_the_other_side._it_turns_the_solder_layer_on_top_and_component_layer_on_bottom._objects_on_component_silk_layer_will_be_greyed_out._if_you_draw_to_silk_lines_will_always_go_to_the_current_top_silk_layer_which_is_solder_now._the_same_happens_to_components_and_their_silk_screen._flip_the_board_again_to_return_to_default_view._why_text_i_add_to_the_solder_side_not_reversed_add_it_while_the_board_is_flipped_tab_._just_selecting_the_solder_side_is_insufficient._new_text_always_reads_correctly_from_the_side_you_re_looking_at._is_it_possible_to_use_an_arbitrary_grid_spacing_yes._you_can_use_the_command_nowiki_setvalue_grid_value_unit_nowiki_._to_do_this-type_-setvalue_grid_x_unit_._the_colon_will_open_the_command_line._replace_x_with_the_desired_grid_spacing_and_unit_with_either_mm_or_mil_._-_type_return_._how_do_i_set_the_origin_in_pcb_the_absolute_origin_is_always_in_the_upper_left_corner_of_the_accessible_area._this_cannot_be_set_to_some_other_place._however_coordinates_of_objects_can_also_be_given_relative_to_the_current_grid._in_the_gtk2_version_of_pcb_coordinates_are_shown_in_the_upper_right_corner_of_the_main_window._the_right_pair_is_the_absolute_position_while_the_left_pair_reflects_the_position_relative_to_an_arbitrary_marker._this_marker_is_set_to_the_current_position_of_the_mouse_by_the_key_sequence_ctrl-m_._you_may_want_to_set_the_marker_to_a_grid_point_or_a_specific_pin._how_do_i_measure_distances_and_dimensions_of_components_use_ctrl-m_to_set_the_origin_and_read_the_distance_of_the_mouse_pointer_relative_to_this_point_on_the_upper_left_of_the_pcb_window._some_objects_like_vias_and_tracks_yield_usefull_information_in_object_reports._access_the_report_of_the_object_currently_under_the_mouse_pointer_with_ctrl-r_._how_do_i_hide_rats_of_specific_nets_in_the_netlist_window_doubleclick_on_the_specific_rat_name_then_press_o_on_your_board_window._your_rats_are_hidden_for_that_net._in_the_netlist_window_an_asterisk_appears_in_from_of_the_rat_name._to_reverse-follow_the_same_procedure._routing_how_do_i_route_a_connection_from_solder_to_component_side_and_back_while_using_the_line_tool_use_the_number_keys_on_top_of_the_keyboard_to_switch_layers._a_via_will_be_placed_automatically_at_the_endpoint_of_the_last_complete_segment._how_do_i_change_the_routing_style_there_is_a_set_of_predefined_sizes_for_routing._the_sets_bear_suggestive_names_signal_power_fat_and_skinny_._hit_the_button_route_style_to_configure_the_sizes_of_the_current_set_to_your_needs._you_can_set_the_names_and_the_default_values_of_these_parameter_sets_in_a_config_file_.pcb_settings_for_the_glossary.html">GTK-HID</a>, or ~/.Xdefaults for the <a href="geda-glossary.html" class="wikilink1" title="geda-glossary.html">Lesstif-HID</a>). Example for such a setting:
558 </p>
559 <pre class="code">route-styles = Signal,1000,3600,2000,1000:Power,2500,6000,3500,1000:Fat,4000,6000,3500,1000:Skinny,600,2402,1181,600</pre>
563 Be sure, to remove any route-style line in ~/.pcb/preferences . Else, the line in settings will be ignored.
564 </p>
567 The line tool knows about different modes to deal with transversal connections. The status line on the bottom of the page tells, which mode is in effect:
568 </p>
569 <ol>
570 <li class="level1"><div class="li"> 45° plus vertical/horizontal (status line: “\_”)</div>
571 </li>
572 <li class="level1"><div class="li"> vertical plus 45° (status line: “_/”)</div>
573 </li>
574 <li class="level1"><div class="li"> either vertical or 45° (status line: “45”)</div>
575 </li>
576 <li class="level1"><div class="li"> arbitrary angle (status line: “all”)</div>
577 </li>
578 </ol>
581 The way to access these modes differs among the <acronym title="Graphical User Interface">GUI</acronym> versions. The current GTK snapshot (v20060288) defaults to “_/” but can be temporarily turned to “\_” with the shift key. You can switch to 45° mode with the slash key “/”. For arbitrary angles, press the period key “.”, or choose “enable all line directions” in the setting menu.
582 </p>
584 </div>
585 <!-- EDIT602 SECTION "I cant't move the components on the other side of the board!" [22433-28105] -->
586 <h1 class="sectionedit603"><a name="routing_issues" id="routing_issues">Routing Issues</a></h1>
587 <div class="level1">
589 </div>
590 <!-- EDIT603 SECTION "Routing Issues" [28106-28136] -->
591 <h2 class="sectionedit604"><a name="i_got_stuck_how_do_i_go_back" id="i_got_stuck_how_do_i_go_back">I got stuck! How do I go back?</a></h2>
592 <div class="level2">
595 The universal undo key [<strong><code>U</code></strong>] works even while in the middle of track layout actions. It will remove the last segment but keep the line tool attached to the mouse. So you can immediately go on routing and find a better way.
596 </p>
598 </div>
599 <!-- EDIT604 SECTION "I got stuck! How do I go back?" [28137-28409] -->
600 <h2 class="sectionedit605"><a name="how_do_i_move_one_set_of_layer_tracks_to_a_different_layer" id="how_do_i_move_one_set_of_layer_tracks_to_a_different_layer">How do I move one set of layer tracks to a different layer?</a></h2>
601 <div class="level2">
602 <ol>
603 <li class="level1"><div class="li"> Select the tracks. It’s easiest to do this if you shut off everything but that layer first (i.e. silk, pins, other layers, etc).</div>
604 </li>
605 <li class="level1"><div class="li"> Now set the current layer to be the new layer. Yes, the layer might get displayed; not a problem as you’ve already selected the tracks you want.</div>
606 </li>
607 <li class="level1"><div class="li"> Press [<strong><code>shift-M</code></strong>] to move all the selected tracks to the current layer.</div>
608 </li>
609 </ol>
611 </div>
612 <!-- EDIT605 SECTION "How do I move one set of layer tracks to a different layer?" [28410-28850] -->
613 <h2 class="sectionedit606"><a name="how_do_i_achieve_open_vias_clear_of_soldermask" id="how_do_i_achieve_open_vias_clear_of_soldermask">How do I achieve open vias clear of soldermask</a></h2>
614 <div class="level2">
617 In pcb vias are covered by soldermask by default. You can achieve open vias by setting their clearance value to a proper value. This can be done individually for every object, or collectively for selections of objects.
618 </p>
621 For individual vias:
622 </p>
623 <ol>
624 <li class="level1"><div class="li"> Turn on the soldermask layer. This will make the k key refer to the soldermask clearance instead of polygon clearance.</div>
625 </li>
626 <li class="level1"><div class="li"> Position the mouse above the via (mouse cursor will change in recent versions of pcb)</div>
627 </li>
628 <li class="level1"><div class="li"> Type [<strong><code>k</code></strong>] several times until soldermask clearance exceeds the diameter of the via pad. Every strike of the key will increase the clearance by 2 mil. The first strike will let the pad of the via pop through the soldermask color. Yet, the actual clearance is only 2 mil at this point. You can decrease the clearance by using the [<strong><code>&lt;shift&gt;-K</code></strong>] key.</div>
629 </li>
630 </ol>
634 For groups of vias:
635 </p>
636 <ol>
637 <li class="level1"><div class="li"> Turn on the solder mask layer.</div>
638 </li>
639 <li class="level1"><div class="li"> select the all the vias you want to clear from soldermask. You may switch off all the other layers to conveniently collect exclusively the vias.</div>
640 </li>
641 <li class="level1"><div class="li"> Type [<strong><code>&lt;ctrl&gt;-K</code></strong>] key several times. [<strong><code>&lt;shift&gt;-&lt;ctrl&gt;-K</code></strong>] will decrease the clearance of all selected objects.</div>
642 </li>
643 </ol>
647 The command interface provides more control over the actual size of the clearance. Type ”:” to get the command line window, then type:
648 </p>
649 <pre class="code">ChangeClearSize(SelectedVias, &lt;delta&gt;)</pre>
652 where <code>&lt;delta&gt;</code> is a size given in 1/100 of a mil. Thus the number 3000 corresponds to 30 mil. Simple integers for <code>&lt;delta&gt;</code> will set the clearance to this value. If the value is preceded by a minus ”-” or a plus ”+” the clearance will be decreased or increased. This also works with <code>SelectedPins</code>, <code>SelectedPads</code>, <code>SelectedLines</code>, <code>SelectedArcs</code> or even <code>SelectedObjects</code>.
653 </p>
655 </div>
656 <!-- EDIT606 SECTION "How do I achieve open vias clear of soldermask" [28851-30626] -->
657 <h2 class="sectionedit607"><a name="how_do_i_change_the_soldermask_clearance_around_a_hole_pad" id="how_do_i_change_the_soldermask_clearance_around_a_hole_pad">How do I change the soldermask clearance around a hole/pad?</a></h2>
658 <div class="level2">
661 By default holes and pads will be cleared by an amount given in the corresponding footprint file. Sometimes this clearance might not be what your design needs. You can change the clearance on the fly for individual holes and pads just like vias. See the paragraph above for the details. If pad clearance is not compatible with the demands of your pcb-fab you may consider to make local copies of the footprint files and change the clearance accordingly.
662 </p>
664 </div>
665 <!-- EDIT607 SECTION "How do I change the soldermask clearance around a hole/pad?" [30627-31153] -->
666 <h2 class="sectionedit608"><a name="how_do_i_change_the_size_of_my_tracks" id="how_do_i_change_the_size_of_my_tracks">How do I change the size of my tracks?</a></h2>
667 <div class="level2">
670 There are a number of ways to change the size of already laid down tracks:
671 </p>
672 <ol>
673 <li class="level1"><div class="li"> Use [<strong><code>s</code></strong>] and [<strong><code>shift-s</code></strong>] to increase and decrease the size of the track currenty under the mouse cursor.</div>
674 </li>
675 <li class="level1"><div class="li"> choose <strong><code>Select/Change_size_of_selected_objects/Decrement_lines_by_4mil</code></strong> from the <strong><code>Select</code></strong> menu. The actual amount of change can be set in <strong><code>File/Preferences/Sizes</code></strong>. This only acts on the tracks. So the selection may contain components, text, vias and the like.</div>
676 </li>
677 <li class="level1"><div class="li"> Select the tracks to be changed and type <strong><code>:ChangeSize(SelectedLines,+4,mils)</code></strong>. The colon gets you to the command line and <strong><code>ChangeSize()</code></strong> is the command version of the previously described action. Replace “<strong><code>+4</code></strong>” by the amount you want to increase the track size. Use the minus sign to decrease the tracksize. If you omit the sign the command sets the track size to the value given.</div>
678 </li>
679 </ol>
681 </div>
682 <!-- EDIT608 SECTION "How do I change the size of my tracks?" [31154-32091] -->
683 <h2 class="sectionedit609"><a name="how_do_i_drive_a_via_to_connect_a_track_to_a_ground_plane_on_a_different_layer" id="how_do_i_drive_a_via_to_connect_a_track_to_a_ground_plane_on_a_different_layer">How do I drive a via to connect a track to a ground plane on a different layer?</a></h2>
684 <div class="level2">
685 <ol>
686 <li class="level1"><div class="li"> Set the GND plane layer as the active layer.</div>
687 </li>
688 <li class="level1"><div class="li"> Select the “via” tool.</div>
689 </li>
690 <li class="level1"><div class="li"> Place the via where you want it to live (left click to place).</div>
691 </li>
692 <li class="level1"><div class="li"> Now select the “thermal” tool.</div>
693 </li>
694 <li class="level1"><div class="li"> Left click on the via you just placed.</div>
695 </li>
696 <li class="level1"><div class="li"> Now change the active layer to your desired routing layer.</div>
697 </li>
698 <li class="level1"><div class="li"> Select the “line” tool.</div>
699 </li>
700 <li class="level1"><div class="li"> Route the track on the active layer to or from the via as usual.</div>
701 </li>
702 </ol>
704 </div>
705 <!-- EDIT609 SECTION "How do I drive a via to connect a track to a ground plane on a different layer?" [32092-32577] -->
706 <h2 class="sectionedit610"><a name="what_is_the_easiest_way_to_create_a_thermal_via" id="what_is_the_easiest_way_to_create_a_thermal_via">What is the easiest way to create a &quot;thermal via&quot;?</a></h2>
707 <div class="level2">
710 A “thermal via” is not a via with a thermal relief. Rather, it&#039;s a via with no thermal relief punched into polygons on both sides of the board. These vias get filled with solder to help create a large thermal mass to be used as a heat sink. For more info, see Freescale App-Note AN4005.
711 </p>
714 Here are some suggestions:
715 </p>
716 <ul>
717 <li class="level1"><div class="li"> Draw a rectangle to comfortably surround the vias. Then, mouse over the rectangle and hit &#039;s&#039;. This will flood the thermal reliefs on the vias. If you want to ever de-solder the part from the back, make sure the pad on the opposite side has the solder resist cleared.</div>
718 </li>
719 <li class="level1"><div class="li"> Just put a normal thermal relief on the via and then shift click on it to cycle through to the one with no relief. </div>
720 </li>
721 </ul>
723 </div>
724 <!-- EDIT610 SECTION "What is the easiest way to create a thermal via?" [32578-33355] -->
725 <h2 class="sectionedit611"><a name="i_want_to_draw_a_track_between_two_segments_on_the_same_net_but_pcb_won_t_let_me_why" id="i_want_to_draw_a_track_between_two_segments_on_the_same_net_but_pcb_won_t_let_me_why">I want to draw a track between two segments on the same net, but PCB won&#039;t let me! Why?</a></h2>
726 <div class="level2">
729 You are likely drawing tracks with auto-DRC on. To connect the two segments, here are some suggestions:
730 </p>
731 <ul>
732 <li class="level1"><div class="li"> DRC enforcement uses the ratsnest to determine where a track is allowed to go. Thus, you must have the ratsnest drawn in order to make connections in auto-DRC mode. Otherwise you will not be allowed to connect (or approach) any copper that is not already connected to your net. (If the rat visibility bothers you, you can hide the rats layer – but the rats must exist).</div>
733 </li>
734 <li class="level1"><div class="li"> You should also refresh the rats regularly when drawing. Hit [<strong><code>o</code></strong>] to redraw/re-optimize the rats. Make sure a rat is visibly connecting the two pieces of metal you want to connect.</div>
735 </li>
736 <li class="level1"><div class="li"> It is also possible that you will experience this situation when drawing tracks between pins in a connector. In this case, it is possible that your track width violates the clearance requirements of the pin field. Try decreasing the pin-to-metal clearance, or use a narrower track width.</div>
737 </li>
738 <li class="level1"><div class="li"> Sometimes this route-blocking behaviour can come about from an error in your netlist. Don&#039;t end refdes&#039;s with lower case letters - they&#039;re reserved for gates within devices. End with upper case or a digit; the lowercase letters are simply ignored.</div>
739 </li>
740 </ul>
742 </div>
743 <!-- EDIT611 SECTION "I want to draw a track between two segments on the same net, but PCB won't let me! Why?" [33356-34674] -->
744 <h2 class="sectionedit612"><a name="pcb_won_t_let_me_connect_to_copper_that_is_not_connected_to_anything" id="pcb_won_t_let_me_connect_to_copper_that_is_not_connected_to_anything">PCB won&#039;t let me connect to copper that is not connected to anything!</a></h2>
745 <div class="level2">
748 This is a known weakness of the Auto-enforce-DRC mode. In this mode, the line tool will only allow you to connect to copper with the same net as the place where the track started.
749 </p>
752 There are two ways to connect to unconnected copper, anyway: Obviously, you can temporarily deactivate Auto-enforce-DRC-clearance in the settings menu. A second way uses the fact that auto-DRC relies on the found flag:
753 </p>
754 <ol>
755 <li class="level1"><div class="li"> enter the “line” mode ([<strong><code>F2</code></strong>]).</div>
756 </li>
757 <li class="level1"><div class="li"> hover the mouse cursor over the unconnected copper.</div>
758 </li>
759 <li class="level1"><div class="li"> press [<strong><code>f</code></strong>] to mark it as “found”.</div>
760 </li>
761 <li class="level1"><div class="li"> start the line from somwhere else. Both should now be marked with the “found” color and should be connectable.</div>
762 </li>
763 </ol>
765 </div>
766 <!-- EDIT612 SECTION "PCB won't let me connect to copper that is not connected to anything!" [34675-35416] -->
767 <h2 class="sectionedit613"><a name="i_want_to_draw_two_vias_very_close_to_each_other_but_pcb_won_t_let_me" id="i_want_to_draw_two_vias_very_close_to_each_other_but_pcb_won_t_let_me">I want to draw two vias very close to each other, but PCB won&#039;t let me!</a></h2>
768 <div class="level2">
771 Unfortunately, older versions of PCB not only prevent you from placing overlapping vias but drop them on load. In december 2010 this overly cautions behavior was fixed. If you really need overlapping vias, you have to install a version of pcb younger than that.
772 </p>
775 The 2011 version of PCB still won&#039;t allow you to place vias so close that their holes overlap. However, it won&#039;t complain if you mangaged to work-around this restriction. E.g. place tiny vias and increase their size afterwards.
777 </p>
779 </div>
780 <!-- EDIT613 SECTION "I want to draw two vias very close to each other, but PCB won't let me!" [35417-35991] -->
781 <h2 class="sectionedit614"><a name="pcb_seems_to_munge_my_components_names_and_complains_that_it_can_t_find_proper_nets_for_the_pins_how_come" id="pcb_seems_to_munge_my_components_names_and_complains_that_it_can_t_find_proper_nets_for_the_pins_how_come">PCB seems to munge my components names and complains that it can&#039;t find proper nets for the pins! How come?</a></h2>
782 <div class="level2">
785 Most likely you named them such that PCB believes they are one part. Lower case letters at the end of a refdes are ignored. Thus, the components U2foo and U2bar both look like U2 to pcb. When building the rat nests pcb is will look for nets to U2 that, of course don&#039;t exist. Lower case letters are meant to differentiate slots of a multi-component. E.g. the four opamp symbols of a quad operational amplifier.<br/>
787 Bottom line: Don&#039;t use lower case letters at the end of a refdes, unless you know what you are doing.
788 </p>
790 </div>
791 <!-- EDIT614 SECTION "PCB seems to munge my components names and complains that it can't find proper nets for the pins! How come?" [35992-36630] -->
792 <h2 class="sectionedit615"><a name="how_can_i_set_color_and_thickness_of_the_rats_nests" id="how_can_i_set_color_and_thickness_of_the_rats_nests">How can I set color and thickness of the rats nests?</a></h2>
793 <div class="level2">
796 You can set the color of the rats in <code>File - Preference - Colors - Main colors</code>
797 </p>
800 There is currently no <acronym title="Graphical User Interface">GUI</acronym> way to set the rat width, but you can edit your <code>$HOME/.pcb/preference</code> file manually. Close all instances of pcb and look for the line that starts with <code>rat-thickness</code>.
801 </p>
804 Values 0..19 are fixed width in screen pixels. Anything larger means PCB units (i.e. 100 means “1 mil”). On zoom, PCB unit rats will scale accordingly.
805 </p>
807 </div>
808 <!-- EDIT615 SECTION "How can I set color and thickness of the rats nests?" [36631-37135] -->
809 <h2 class="sectionedit616"><a name="where_is_that_last_remaining_rat" id="where_is_that_last_remaining_rat">Where is that last remaining rat?</a></h2>
810 <div class="level2">
813 Sometimes remaining rats are hard to see, because they have zero length. This will be the case if a via is missing for some reason. You can make them pop into your eye by setting the rat thickness to some big value e.g. 3000 mil. Rat thickness is set in <code>$HOME/.pcb/preference</code>.
814 </p>
816 </div>
817 <!-- EDIT616 SECTION "Where is that last remaining rat?" [37136-37463] -->
818 <h1 class="sectionedit617"><a name="beyond_tracks_and_footprints" id="beyond_tracks_and_footprints">Beyond tracks and footprints</a></h1>
819 <div class="level1">
821 </div>
822 <!-- EDIT617 SECTION "Beyond tracks and footprints" [37464-37506] -->
823 <h2 class="sectionedit618"><a name="how_do_i_trace_a_drawing_a_print_or_another_pcb" id="how_do_i_trace_a_drawing_a_print_or_another_pcb">How do I trace a drawing, a print, or another PCB?</a></h2>
824 <div class="level2">
827 See the page <a href="http://www.delorie.com/pcb/bg-image.html" class="urlextern" title="http://www.delorie.com/pcb/bg-image.html" rel="nofollow">http://www.delorie.com/pcb/bg-image.html</a> at DJ Delorie&#039;s PCB HID website.
828 </p>
831 This is a great way to trace hand-drawn artwork or another PCB, say one you made in software with a proprietary format, which you&#039;d now like to &#039;unlock&#039;. Furthermore, you can use the background image as tool for making board revisions or redesigns.
832 </p>
835 If you don&#039;t like to use PCB confined to the area of the board, i.e. if you want margins around your board, then add them in the GIMP. I like to make a 1.00000 inch margin around the board. When you set your PCB size in PCB, you&#039;ll want to add the margin area. CTRL-M will help you verify the scaling. Also, the time to correct distortions from your scanner, or from your drawing is before you load it, in the GIMP or the like.
836 </p>
838 </div>
839 <!-- EDIT618 SECTION "How do I trace a drawing, a print, or another PCB?" [37507-38347] -->
840 <h2 class="sectionedit619"><a name="i_can_t_copy_component_pads_in_a_layout_what_gives" id="i_can_t_copy_component_pads_in_a_layout_what_gives">I can&#039;t copy component pads in a layout. What gives?</a></h2>
841 <div class="level2">
844 <strong>Question:</strong> I want to copy a section of my existing layout to another spot.
845 </p>
848 I can select the existing area. Everything turns pretty blue.
849 </p>
852 “Buffer”–&gt;“Copy Selection To Buffer” seems to succeed (no complaints).
853 </p>
856 Then I go to paste the copied area… and all that moves are a couple
857 of traces and some vias. The pads I&#039;ve painstakingly created
858 aren&#039;t copied. What gives!?!?!?
859 </p>
862 <strong>Answer:</strong> If the silk layer is off, you can&#039;t copy elements through the paste
863 buffer. Weird, but that&#039;s how it works. Therefore, turn on the silk
864 layer before trying to copy a section of a layout.
865 </p>
867 </div>
868 <!-- EDIT619 SECTION "I can't copy component pads in a layout. What gives?" [38348-39002] -->
869 <h2 class="sectionedit620"><a name="how_do_i_fill_areas_with_copper" id="how_do_i_fill_areas_with_copper">How do I fill areas with copper?</a></h2>
870 <div class="level2">
873 Use rectangles and polygon planes. These items will always avoid vias, pads and pins. Tracks are also avoided, if they have the clear polygons flag set. (menu: Settings/Enable_new_lines_clear_polygons). Since version 20070208 of pcb the resulting polygon will be one contiguous piece. Isolated snippets are removed.
874 </p>
876 </div>
877 <!-- EDIT620 SECTION "How do I fill areas with copper?" [39003-39366] -->
878 <h2 class="sectionedit621"><a name="how_can_i_assign_my_polygon_to_a_net" id="how_can_i_assign_my_polygon_to_a_net">How can I assign my polygon to a net?</a></h2>
879 <div class="level2">
882 Polygons are not “assigned” to nets, they&#039;re connected to them. Pads are the only carriers of netnames in pcb. This means, you need to design some copper to connect the polygon with a pad. The net of the pad automatically transfers to the polygon.
883 </p>
885 </div>
886 <!-- EDIT621 SECTION "How can I assign my polygon to a net?" [39367-39669] -->
887 <h2 class="sectionedit622"><a name="how_can_i_connect_tracks_pads_or_vias_to_my_polygon" id="how_can_i_connect_tracks_pads_or_vias_to_my_polygon">How can I connect tracks, pads, or vias to my polygon?</a></h2>
888 <div class="level2">
891 There are different ways to adequately connect different types of objects to a polygon:
892 </p>
893 <ul>
894 <li class="level1"><div class="li"> tracks: Set the join flag of the track. You can do this with the [<strong><code>j</code></strong>] key, while the mouse hovers above the track. Alternatively you can select the lines and apply the command “SetFlag(selected,join)”. For new lines, you can uncheck the new-lines-clear-polygons in the settings menu. The polygon will immediately flow into the track.</div>
895 </li>
896 <li class="level1"><div class="li"> pads: Currently, there is no way to directly connect a polygon to a pad. Draw a track without the join flag from the pad to the polygon. (see above) </div>
897 </li>
898 <li class="level1"><div class="li"> pins and vias: Choose the thermal tool (“THRM”). Select the layer the polygon sits on. Shift-Click on the via to circle through the available styles of the connection. </div>
899 </li>
900 <li class="level1"><div class="li"> polygons: Just define them geometrically overlapping.</div>
901 </li>
902 </ul>
904 </div>
905 <!-- EDIT622 SECTION "How can I connect tracks, pads, or vias to my polygon?" [39670-40556] -->
906 <h2 class="sectionedit623"><a name="the_polygons_are_shorting_my_tracks_what_can_i_do_about_it" id="the_polygons_are_shorting_my_tracks_what_can_i_do_about_it">The polygons are shorting my tracks! What can I do about it?</a></h2>
907 <div class="level2">
910 You didn’t have “Enable_new_lines_clear_polygons” checked in the settings menu when you layed down the tracks. Enter <code>changejoin(selected)</code> in the command window to toggle this flag for all tracks that are currently selected. The keyboard shortcut to this action is [<strong><code>shift-j</code></strong>].
911 If you want to set or clear the join flag rather than toggle it, you can use the commands <code>SetFlag(selected, join)</code> and <code>ClrFlag(selected, join)</code>. See the SetFlag description in the <a href="http://pcb.gpleda.org/pcb-cvs/pcb.html#SetFlag-Action" class="urlextern" title="http://pcb.gpleda.org/pcb-cvs/pcb.html#SetFlag-Action" rel="nofollow">pcb manual</a> for more details on these commands.
912 </p>
914 </div>
915 <!-- EDIT623 SECTION "The polygons are shorting my tracks! What can I do about it?" [40557-41219] -->
916 <h2 class="sectionedit624"><a name="how_do_i_change_polygon_clearance" id="how_do_i_change_polygon_clearance">How do I change polygon clearance?</a></h2>
917 <div class="level2">
920 In pcb, the polygon itself has no built-in clearance. It is the tracks, pads and pins that bear this property. This means, you can adjust the clearance individually:
921 </p>
924 Make sure, the soldermask layer is not active. Else the following will apply to the soldermask rather than to the polygon. Press [<code>k</code>] to increase the clearance of the object under the cursor. Use [<code>ctrl-k</code>] to increase the clearence of selected objects. Add the [<code>shift</code>] modifier to decrease the clearence. To change a whole track press [<code>f</code>] to find all segments that are connected to the object under the cursor and apply the action <code>select(connection)</code>.
925 </p>
928 The amount of the increment can be configured in the dialog <code>File/Preference/Increments</code>.
929 </p>
932 The above only applies to one object at a time. You can manipulate the clearance of all selected objects with the action <code>ChangeClearSize(Selected,&lt;amount&gt;,&lt;unit&gt;)</code>. The parameter <code>&lt;amount&gt;</code> should be a number. A prefixed sign means increment, or decrement. A prefixed <code>=</code> sets the clearance to the following value. The parameter can be <code>mil</code> or <code>mm</code>. If not specified the units will default to the internal unit of 0.01 mil.
933 </p>
936 In addition, there is a special action that acts only on objects with clearance below a given minimum: <code>MinClearGap(Selected,&lt;amount&gt;,&lt;unit&gt;)</code>.
937 </p>
939 </div>
940 <!-- EDIT624 SECTION "How do I change polygon clearance?" [41220-42580] -->
941 <h2 class="sectionedit625"><a name="how_do_i_hide_the_polygons_while_i_edit_the_layout" id="how_do_i_hide_the_polygons_while_i_edit_the_layout">How do I hide the polygons while I edit the layout?</a></h2>
942 <div class="level2">
945 Put the polygons (and rectangles) on a separate layer. Use the preference to make sure, this layer is not in the same group as the tracks. Disable the layer by a click on the corresponding layer button in the main window. After you are finished with the changes, use the preference dialog to let the polygon layer join the layer of the tracks. You will have to save and reload the layout to trigger recalculation of polygons so they are adapted to your edits. Alternatively a restart will recalculate the polygons too.
946 </p>
948 </div>
949 <!-- EDIT625 SECTION "How do I hide the polygons while I edit the layout?" [42581-43165] -->
950 <h2 class="sectionedit626"><a name="polygons_are_making_the_gui_sluggish_what_i_can_do_about_it" id="polygons_are_making_the_gui_sluggish_what_i_can_do_about_it">Polygons are making the GUI sluggish. What I can do about it?</a></h2>
951 <div class="level2">
954 Parts of the polygon that are not connected to some net are automatically eliminated. This effectively removes <a href="geda-glossary.html" class="wikilink1" title="geda-glossary.html">dead copper</a>. While this is desirable for the actual board, it requires calculation of quite extensive algorithms. So it is not necessarily a bug, but a price to be paid for a powerful feature. Still, there is a couple of things you can do to improve the situation:
955 </p>
956 <ul>
957 <li class="level1"><div class="li"> Temporarily hide the polygons. (see above)</div>
958 </li>
959 <li class="level1"><div class="li"> Choose “thin draw poly” from the settings menu to display only the outlines of the polygons and disable dead copper removal. In recent versions of gschem, i.e. later than september 2007, you can select through the polygons. </div>
960 </li>
961 <li class="level1"><div class="li"> Make sure, you don&#039;t have redundant polygons defined, which multiply overlay the same area. These polygons won&#039;t display becaus they shade each other. But they demand calculation resources. The best way to check for redundant polygons is to edit the source of your layout with an ascii editor. </div>
962 </li>
963 </ul>
965 </div>
966 <!-- EDIT626 SECTION "Polygons are making the GUI sluggish. What I can do about it?" [43166-44209] -->
967 <h2 class="sectionedit627"><a name="after_i_defined_those_ground_planes_pcb_takes_ages_to_load_how_come" id="after_i_defined_those_ground_planes_pcb_takes_ages_to_load_how_come">After I defined those ground planes, pcb takes ages to load. How come?</a></h2>
968 <div class="level2">
971 Polygon calculation is potentially an expensive operation in terms of processor cyles. Unless your layout is pretty complex, you most likely have redundant polygons defined. Look into the source of your layout to find and delete unnecessary polygons. If this does not apply, see above for possible measures to ameliorate the situation.
972 </p>
974 </div>
975 <!-- EDIT627 SECTION "After I defined those ground planes, pcb takes ages to load. How come?" [44210-44630] -->
976 <h2 class="sectionedit628"><a name="how_do_i_edit_polygons" id="how_do_i_edit_polygons">How do I edit polygons?</a></h2>
977 <div class="level2">
980 There are four basic ways to edit polygon outlines. You can move and delete vertices and you can insert vertices using two techniques. Polygons can be edited equally well in “thin line draw” mode (settings –&gt; enable thin line draw) or in normal mode. Moving a vertex is easily accomplished by un-selecting your polygon and then clicking and dragging that vertex to a new location. To delete a vertex, a corner in your polygon, put your crosshairs over the point and hit ‘delete’ on the keyboard. To insert a vertex, you’ll use the insert tool (’insert’ keystroke). Start by clicking the edge you want to split with a new point. Click and drag a new point into the polygon. A variation on this technique is 1) click to select, followed by 2) click to place new vertex.
981 </p>
984 (NOTE: Inserting points into polygon will generally work ONLY with “all direction lines” enabled (’settings –&gt; enable all direction lines’). This is because PCB has a powerful 45/90 degree constraints system. If you try to insert new vertices into a polygon that don’t fall onto lines of proper 45 and 90 degree constraints, PCB disallows the action!)
985 </p>
987 </div>
988 <!-- EDIT628 SECTION "How do I edit polygons?" [44631-45816] -->
989 <h2 class="sectionedit629"><a name="how_do_i_place_vias_that_connect_to_a_polygon_for_full_thermal_dissipation_or_full_shielding_integrity" id="how_do_i_place_vias_that_connect_to_a_polygon_for_full_thermal_dissipation_or_full_shielding_integrity">How do I place vias that connect to a polygon for full thermal dissipation or full shielding integrity?</a></h2>
990 <div class="level2">
993 Often it’s useful to have vias connect completely to a polygon (a field of copper) for heat transfer– the apparent problem is that PCB polygons have only a single “clear pins/vias” flag for the entire polygon (toggled by the [<strong><code>s</code></strong>] key). Our goal is to only connect some of the pins/vias to the polygon, but to connect them better than a thermal does. Here are a few ways to do this:
994 </p>
997 One way, you’ll make an object that’s almost just like a thermal in that it goes between your via and the polygon–the difference is that you’ll actually create an annulus to completely fill the space between the hole and polygon (which because it’s clearance is turned on, is not connected to the pin). This annulus is four arc segments. You can copy these four items to the buffer to create a “zero-clearance thermal tool”. The drawback of this trick is that when you change via size, you’ll also have to modify the size of these filler parts.
998 </p>
1001 The arcs allow you to use this fill trick in tight places by only placing, say two of the four arcs.
1002 </p>
1005 Another trick is to make a zero-length line. Take a single line segment and move the end-point on top of the start-point. Now you have a “single point line” (a circle) with the diameter equal to the line thickness. Move to different layers ([<strong><code>m</code></strong>] key) as you see fit. Place this object centered on your via to connect it to a polygon.
1006 </p>
1009 Power-users may want to keep a small custom library of these parts by saving them as elements. It’s also handy to put these “parts” in one of your PCB buffers so they’re at your fingertips.
1010 </p>
1013 You can also add another polygon on-top of the polygon to which you want to connect you vias. You’ll un-set the “clear pins/vias” flag and the vias will be connected to the larger polygon underneath.
1014 </p>
1016 </div>
1017 <!-- EDIT629 SECTION "How do I place vias that connect to a polygon for full thermal dissipation or full shielding integrity?" [45817-47739] -->
1018 <h2 class="sectionedit630"><a name="can_polygons_be_un-masked_can_a_polygon_be_made_bare-copper_with_no_solder_mask" id="can_polygons_be_un-masked_can_a_polygon_be_made_bare-copper_with_no_solder_mask">Can polygons be un-masked? (Can a polygon be made bare-copper with no solder mask?)</a></h2>
1019 <div class="level2">
1022 Currently, there is no way to directly make polgons clear solder mask. The usual workaround is to work with pads.
1023 </p>
1024 <ol>
1025 <li class="level1"><div class="li"> Draw a track in the middle of the desired no solder mask area. Every track will become a pad.</div>
1026 </li>
1027 <li class="level1"><div class="li"> Select the tracks</div>
1028 </li>
1029 <li class="level1"><div class="li"> Do convert-selection-to-element from the select menu</div>
1030 </li>
1031 <li class="level1"><div class="li"> Activate the solder mask layer. The solder mask should keep clear of the tracks</div>
1032 </li>
1033 <li class="level1"><div class="li"> Increase the clearance of the pads to match the desired bare copper area. To do this, press [k] while the mouse cursor hovers above the pads.</div>
1034 </li>
1035 <li class="level1"><div class="li"> Optionally press q to set the square flag of the pads.</div>
1036 </li>
1037 </ol>
1040 While the pad witdth is limited to 250 mil, clearance can be arbitrary.
1041 </p>
1043 </div>
1044 <!-- EDIT630 SECTION "Can polygons be un-masked? (Can a polygon be made bare-copper with no solder mask?)" [47740-48489] -->
1045 <h2 class="sectionedit631"><a name="how_can_i_increase_the_size_of_all_pins" id="how_can_i_increase_the_size_of_all_pins">How can I increase the size of all pins?</a></h2>
1046 <div class="level2">
1049 This is a two step process. First select the objects you want to manipulate. Then act on the selection:
1050 </p>
1051 <ol>
1052 <li class="level1"><div class="li"> select all components. You may shut of all layers except silk so the select tool doesn&#039;t catch tracks.</div>
1053 </li>
1054 <li class="level1"><div class="li"> from the menu chose select→change_size_of_selected_objects→Pins_+10_mil</div>
1055 </li>
1056 </ol>
1059 You may rip off the sub menu at the dashed line to make it stay on the screen for convenient repeated application.
1060 </p>
1063 Alternatively, issue the ChangeSize action with the command tool:
1064 </p>
1065 <ul>
1066 <li class="level1"><div class="li"> Type a colon to open the command line. </div>
1067 </li>
1068 <li class="level1"><div class="li"> In the command line type&lt;br&gt; </div>
1069 </li>
1070 </ul>
1071 <pre class="code">ChangeSize(SelectedPins, SIZE)</pre>
1075 Replace SIZE with the desired size, given in 1/100 mil. 1mm = 3937. If SIZE is prefixed by ”-” the size is decreased. If the prefix is ”+”, the size is increased. If there is no sign, it is interpreted as an absolute value. Refer to the <a href="http://pcb.gpleda.org/pcb-cvs/pcb.html#ChangeSize-Action" class="urlextern" title="http://pcb.gpleda.org/pcb-cvs/pcb.html#ChangeSize-Action" rel="nofollow">pcb manual</a> for the syntax of the ChangeSize action.
1076 </p>
1078 </div>
1079 <!-- EDIT631 SECTION "How can I increase the size of all pins?" [48490-49494] -->
1080 <h2 class="sectionedit632"><a name="how_do_i_place_mounting_holes" id="how_do_i_place_mounting_holes">How do I place mounting holes?</a></h2>
1081 <div class="level2">
1084 Use a footprint for the mounting hole or place a via.
1085 </p>
1088 If the pads surrounding the mounting hole need to be electrically connected then you should show the connection in your schematic. Add a symbol for the mounting hole and change its footprint attribute.
1089 </p>
1092 My preference is to create PCB footprints for the various types of mounting hardware. I have a variety of silkscreens for various hardware combinations (hex nut, hex nut with washer, etc.) The silkscreen provides a convenient placement reference during PCB layout.
1093 </p>
1096 For footprint examples see <a href="http://www.luciani.org/geda/pcb/pcb-footprint-list.html#Hardware" class="urlextern" title="http://www.luciani.org/geda/pcb/pcb-footprint-list.html#Hardware" rel="nofollow">http://www.luciani.org/geda/pcb/pcb-footprint-list.html#Hardware</a>.
1097 </p>
1099 </div>
1100 <!-- EDIT632 SECTION "How do I place mounting holes?" [49495-50159] -->
1101 <h2 class="sectionedit633"><a name="why_is_it_possible_to_make_a_thermal_for_pin_but_not_for_a_pad" id="why_is_it_possible_to_make_a_thermal_for_pin_but_not_for_a_pad">Why is it possible to make a thermal for pin, but not for a pad?</a></h2>
1102 <div class="level2">
1105 The reason is that pins usually have sufficient spacing that the plane surrounding them remains intact on all sides and pads usually are so tightly spaced that they do not. Because of this you must manually draw the thermal “fingers” to connect the pad to the ground plane. Be sure that you have the settings such that new lines connect to planes when you draw them. If you need to make several such thermals, spend a little time making the first one just the way you want then copy the fingers to the buffer and paste it where you want the others.
1106 </p>
1108 </div>
1109 <!-- EDIT633 SECTION "Why is it possible to make a thermal for pin, but not for a pad?" [50160-50791] -->
1110 <h2 class="sectionedit634"><a name="can_pcb_be_used_to_make_single_layer_boards" id="can_pcb_be_used_to_make_single_layer_boards">Can PCB be used to make single layer boards?</a></h2>
1111 <div class="level2">
1114 It&#039;s all just names when you&#039;re doing single sided. There&#039;s no such
1115 thing as a single sided board in pcb - just a double sided board with nothing
1116 on one side.
1117 </p>
1120 Design for two-sided, but with all the traces on the solder side. If you use
1121 the autorouter, turn off all but the bottom layer. This will make the autorouter
1122 stick to that layer. If you need wire jumpers, you have two options to let pcb know
1123 there is a valid connection: You can draw tracks on top layer similar to a two layer
1124 layout. Alternatively you can Create a “jumper” symbol in the schematic and put that
1125 in places where you need a jumper. This is likely to be a major pain, but you can
1126 enforce dimensions of the jumpers this way if you care.
1127 </p>
1130 Single sided boards do not have plated holes, so pad diameter for pins must be
1131 greater, usually two to three times the drill size. Some footprints in the default
1132 library have very small pads which will be too weak if used for single sided board.
1133 Tweak them to your needs and place them in a local library.
1134 </p>
1137 When you dump your gerbers, delete the component side one and rename
1138 the plated-holes one to unplated-holes. Voila! A single sided board.
1139 </p>
1141 </div>
1142 <!-- EDIT634 SECTION "Can PCB be used to make single layer boards?" [50792-52017] -->
1143 <h2 class="sectionedit635"><a name="what_resources_exist_to_process_pcb_files_using_scripts" id="what_resources_exist_to_process_pcb_files_using_scripts">What resources exist to process PCB files using scripts?</a></h2>
1144 <div class="level2">
1147 One of PCB&#039;s great features is that it uses an easily understood <acronym title="American Standard Code for Information Interchange">ASCII</acronym> file format. Therefore, many people use scripts (commonly <acronym title="Practical Extraction and Report Language">Perl</acronym>) to process their boards in various ways. You can use these scripts either as they are, or modify them to suit your own goals. Here are some links to available scripts:
1148 </p>
1149 <ol>
1150 <li class="level1"><div class="li"> John Luciani has a large number of <a href="http://www.luciani.org/geda/pcb/pcb-perl-library.html" class="urlextern" title="http://www.luciani.org/geda/pcb/pcb-perl-library.html" rel="nofollow">scripts</a> available on <a href="http://www.luciani.org" class="urlextern" title="http://www.luciani.org" rel="nofollow"> his website</a>. Included in his collection are scripts for generating footprints, as well as </div>
1151 </li>
1152 <li class="level1"><div class="li"> David Rowe has scripts for updating elements as well as adding/subtracting PCB files from each other on <a href="http://www.rowetel.com/perl4pcb.html" class="urlextern" title="http://www.rowetel.com/perl4pcb.html" rel="nofollow">his website.</a></div>
1153 </li>
1154 <li class="level1"><div class="li"> Stuart Brorson wrote a simple script which generates footprints for two terminal SMT passives. A gzipped tarball is available <a href="http://www.brorson.com/gEDA/Smtgen.pl.gz" class="urlextern" title="http://www.brorson.com/gEDA/Smtgen.pl.gz" rel="nofollow"> here </a>.</div>
1155 </li>
1156 <li class="level1"><div class="li"> The website <a href="http://www.gedasymbols.org/" class="urlextern" title="http://www.gedasymbols.org/" rel="nofollow"> gedasymbols.org</a> has gathered a collection of footprints, symbols, scripts, and other materials from many different gEDA contributors. The website is organized by contributor, so if you take the time to browse around there, you may find exactly what you are looking for!</div>
1157 </li>
1158 </ol>
1160 </div>
1161 <!-- EDIT635 SECTION "What resources exist to process PCB files using scripts?" [52018-53303] -->
1162 <h2 class="sectionedit636"><a name="how_do_i_import_external_vector_graphics" id="how_do_i_import_external_vector_graphics">How do I import external vector graphics?</a></h2>
1163 <div class="level2">
1166 There is a third party open source utility called <a href="http://www.pstoedit.net/" class="urlextern" title="http://www.pstoedit.net/" rel="nofollow">pstoedit</a> that converts postscript data to pcb format. It is included in most major linux distributions. You can use your favorite vector graphics utility to produce a logo or any kind of fancy layout. Export as eps if you can and make sure that your logo fits into the bounding box (check with a postscript viewer such as ggv). If there is no eps export available, you can produce postscript by printing to a file. In this case you may add a bounding box with <a href="http://www.cs.wisc.edu/~ghost/doc/gnu/6.53/Ps2epsi.htm" class="urlextern" title="http://www.cs.wisc.edu/~ghost/doc/gnu/6.53/Ps2epsi.htm" rel="nofollow">ps2epsi</a>. Call pstoedit with the option ”<code>-f pcb</code>” to produce a valid pcb file that contains the graphics as tracks on layer 1. Load this file to pcb. The graphics will sit somewhere on the lower left of the view port. You may have to zoom out to get it on the screen.
1167 </p>
1170 Import of external vector graphics is usefull if an irregular shape of the pcb is required. Use the cut buffer to copy the shape to your actual design.
1171 </p>
1173 </div>
1174 <!-- EDIT636 SECTION "How do I import external vector graphics?" [53304-54383] -->
1175 <h2 class="sectionedit637"><a name="is_there_a_way_to_import_a_dxf_drawing_from_mechanical_cad_applications" id="is_there_a_way_to_import_a_dxf_drawing_from_mechanical_cad_applications">Is there a way to import a DXF drawing from mechanical CAD applications?</a></h2>
1176 <div class="level2">
1179 There is no import filter to directly load a DXF file to pcb. However, the open source application <a href="http://www.qcad.org" class="urlextern" title="http://www.qcad.org" rel="nofollow">qcad</a> can open DXF files and export them as postscript. The tool pstoedit can turn this postscript file into a format readable by pcb (see above).
1180 </p>
1182 </div>
1183 <!-- EDIT637 SECTION "Is there a way to import a DXF drawing from mechanical CAD applications?" [54384-54738] -->
1184 <h2 class="sectionedit638"><a name="what_is_the_best_way_to_do_weird_footprints" id="what_is_the_best_way_to_do_weird_footprints">What is the best way to do weird footprints?</a></h2>
1185 <div class="level2">
1188 Sometimes footprints call for shapes that are difficult to achieve with the restricted graphics <acronym title="Graphical User Interface">GUI</acronym> of pcb. It may be easier to start with a the vector drawing application inkscape and convert to pcb.
1189 In inkscape:
1190 </p>
1191 <ul>
1192 <li class="level1"><div class="li"> draw the weird shape with lines. Lines don&#039;t have to be straight.</div>
1193 </li>
1194 <li class="level1"><div class="li"> save as eps (uncheck “make bounding box around page”)</div>
1195 </li>
1196 </ul>
1200 Convert to pcb format:
1201 </p>
1202 <ul>
1203 <li class="level1"><div class="li"> pstoedit -f pcb &gt; footprint.pcb</div>
1204 </li>
1205 </ul>
1209 In pcb do:
1210 </p>
1211 <ul>
1212 <li class="level1"><div class="li"> File - load-layout-data-to-buffer</div>
1213 </li>
1214 <li class="level1"><div class="li"> edit to your needs (lines only, no polygons)</div>
1215 </li>
1216 <li class="level1"><div class="li"> select the bunch of lines</div>
1217 </li>
1218 <li class="level1"><div class="li"> copy to buffer ( ctrl-c )</div>
1219 </li>
1220 <li class="level1"><div class="li"> Buffer - convert-buffer-to-element</div>
1221 </li>
1222 <li class="level1"><div class="li"> Buffer - save-buffer-elements-to-file</div>
1223 </li>
1224 </ul>
1228 In a text editor:
1229 </p>
1230 <ul>
1231 <li class="level1"><div class="li"> add the same pin number to all the lines with search and replace</div>
1232 </li>
1233 <li class="level1"><div class="li"> save as *.fp at a place where pcb is looking for footprint libraries</div>
1234 </li>
1235 </ul>
1237 </div>
1238 <!-- EDIT638 SECTION "What is the best way to do weird footprints?" [54739-55600] -->
1239 <h2 class="sectionedit639"><a name="how_do_i_attach_a_name_to_my_layout" id="how_do_i_attach_a_name_to_my_layout">How Do I attach a name to my layout?</a></h2>
1240 <div class="level2">
1243 You can set the name of the current pcb with <code>Menu Edit - Edit name of - layout</code>. This sets the title attribute of the layout. This attribute is used for the export actions. It does not interfere with the file name.
1244 </p>
1246 </div>
1247 <!-- EDIT639 SECTION "How Do I attach a name to my layout?" [55601-55873] -->
1248 <h2 class="sectionedit640"><a name="is_there_a_way_to_do_multiple_instances_of_a_subcircuits" id="is_there_a_way_to_do_multiple_instances_of_a_subcircuits">Is there a way to do multiple instances of a subcircuits?</a></h2>
1249 <div class="level2">
1252 The <acronym title="Graphical User Interface">GUI</acronym> provides no way to do similar subcircuits automatically. You can copy groups of tracks and vias. However, you have to place the footprints manually. Deactivate “Auto-enforce-DRC-Clearrance” in the edit menu during placement. Else pcb won&#039;t let you connect the footprints with the copied tracks and vias.
1253 </p>
1256 John Luciani wrote a pair of perl scripts that can do better than that. The script sch-matrix places multiple copies of a basic block on the sheet. It increments the numbers and positions of the symbols as needed. The layout script pcb-matrix arranges multiple copies of a sample layout in a matrix way. The result is a matching pair of schematic and layout with a subcircuit repeated multiple times. See <a href="http://www.luciani.org/geda/util/matrix/index.html" class="urlextern" title="http://www.luciani.org/geda/util/matrix/index.html" rel="nofollow">Johns website</a> for the details and a download of the scripts.
1257 </p>
1260 The pair of scripts was written a few years ago and is not used regularily. They may need to be updated when used with recent versions of pcb.
1261 Contribution of bug reports and/or patches are welcome.
1262 </p>
1264 </div>
1265 <!-- EDIT640 SECTION "Is there a way to do multiple instances of a subcircuits?" [55874-56981] -->
1266 <h1 class="sectionedit641"><a name="auto_router" id="auto_router">Auto Router</a></h1>
1267 <div class="level1">
1269 </div>
1270 <!-- EDIT641 SECTION "Auto Router" [56982-57011] -->
1271 <h2 class="sectionedit642"><a name="how_do_i_make_the_most_of_the_auto_router" id="how_do_i_make_the_most_of_the_auto_router">How do I make the most of the auto router?</a></h2>
1272 <div class="level2">
1273 <ol>
1274 <li class="level1"><div class="li"> Turn off visibility of any layers you don&#039;t want the router using.</div>
1275 </li>
1276 <li class="level1"><div class="li"> Turn of via visibility if you don&#039;t want it to introduce any new vias.</div>
1277 </li>
1278 <li class="level1"><div class="li"> Use only plain rectangles for power/ground planes that you want the router to use. (Use the rectangle tool rather than the polygon tool!)</div>
1279 </li>
1280 <li class="level1"><div class="li"> Make at least one connection from any plane you want the router to use to the net you want it to connect to.</div>
1281 </li>
1282 <li class="level1"><div class="li"> Draw continuous lines on all routing layers to outline keep-out zones.</div>
1283 </li>
1284 <li class="level1"><div class="li"> Use routing styles in the netlist to have per-net routing styles.</div>
1285 </li>
1286 <li class="level1"><div class="li"> Set the current routing style for any nets not having a defined route style in the netlist.</div>
1287 </li>
1288 <li class="level1"><div class="li"> Disable any nets that you don&#039;t want the autorouter to route – double-click them in the netlist window to add/remove the “*”.</div>
1289 </li>
1290 <li class="level1"><div class="li"> Create a fresh rat&#039;s nest. (press the [o]-key)</div>
1291 </li>
1292 <li class="level1"><div class="li"> Select “show autorouter trials” in the settings menu if you want to watch what&#039;s happening.</div>
1293 </li>
1294 <li class="level1"><div class="li"> Choose “autoroute all rats” in the connection menu.</div>
1295 </li>
1296 </ol>
1300 Note on disabled nets: If you will be manually routing these later not using planes, it is usually better to let the autorouter route them then rip them up yourself afterwards. If you plan to use a ground/power plane manually, consider making it from one or more pure rectangles and letting the autorouter have a go at it.
1301 </p>
1304 If you really want to muck with the router because you have a special design, e.g. all through-hole components you can mess with layer directional
1305 costs by editing the autoroute.c source file and changing the directional costs in lines 929-940. and try again. Even more mucking about with costs is possible in lines 4540-4569, but it&#039;s probably not such a good idea unless you really just want to experiment.
1306 </p>
1308 </div>
1309 <!-- EDIT642 SECTION "How do I make the most of the auto router?" [57012-58779] -->
1310 <h2 class="sectionedit643"><a name="how_do_i_force_the_autorouter_to_only_put_traces_on_a_particular_layer" id="how_do_i_force_the_autorouter_to_only_put_traces_on_a_particular_layer">How do I force the autorouter to only put traces on a particular layer?</a></h2>
1311 <div class="level2">
1314 Just unselect the layers you don’t want (usually green and blue) by clicking on the name of the layer. then press autoroute.
1315 </p>
1317 </div>
1318 <!-- EDIT643 SECTION "How do I force the autorouter to only put traces on a particular layer?" [58780-58991] -->
1319 <h2 class="sectionedit644"><a name="how_do_i_make_autorouter_leave_particular_nets_alone" id="how_do_i_make_autorouter_leave_particular_nets_alone">How do I make autorouter leave particular nets alone?</a></h2>
1320 <div class="level2">
1323 Open up the netlist window. It has options for including or excluding nets from the ratlist. If you use the GTK-HID double-click a route to disable it. Make sure, only the nets you want are enabled. Optimize the rats with key [o]. Do “autoroute all rats”.
1324 </p>
1326 </div>
1327 <!-- EDIT644 SECTION "How do I make autorouter leave particular nets alone?" [58992-59316] -->
1328 <h2 class="sectionedit645"><a name="how_do_i_force_the_autorouter_to_route_only_within_my_pcb_outline" id="how_do_i_force_the_autorouter_to_route_only_within_my_pcb_outline">How do I force the autorouter to route only within my pcb outline?</a></h2>
1329 <div class="level2">
1332 You can have the autorouter work only within a given area by drawing a copper polygon conforming to your board’s boundary and placing it in each layer you’re trying to autoroute. You can also use this trick to autoroute only with small areas. Of course, if you accidentally have a net touching the polygon, all routes will get shorted to that net.
1333 </p>
1335 </div>
1336 <!-- EDIT645 SECTION "How do I force the autorouter to route only within my pcb outline?" [59317-59748] -->
1337 <h2 class="sectionedit646"><a name="how_do_i_route_power_and_ground_planes_with_the_autorouter" id="how_do_i_route_power_and_ground_planes_with_the_autorouter">How do I route power and ground planes with the autorouter?</a></h2>
1338 <div class="level2">
1341 Connect the polygon that will become your power planes to a net and the autorouter will figure it all out. You may need some trick polygon clearances to get power routing _and_ routing within a board outline.
1342 </p>
1344 </div>
1345 <!-- EDIT646 SECTION "How do I route power and ground planes with the autorouter?" [59749-60030] -->
1346 <h2 class="sectionedit647"><a name="the_layout_produced_by_the_autorouter_is_inefficient" id="the_layout_produced_by_the_autorouter_is_inefficient">The layout produced by the autorouter is inefficient!</a></h2>
1347 <div class="level2">
1350 This is a technological limitation of the current auto router. It is gridless and uses geometric rectangles only.
1351 </p>
1353 </div>
1354 <!-- EDIT647 SECTION "The layout produced by the autorouter is inefficient!" [60031-60211] -->
1355 <h2 class="sectionedit648"><a name="the_layout_produced_by_the_autorouter_is_ugly" id="the_layout_produced_by_the_autorouter_is_ugly">The layout produced by the autorouter is ugly!</a></h2>
1356 <div class="level2">
1359 Have you tried the various clean-up tools under connects–&gt;optimize routed tracks?
1360 </p>
1362 </div>
1363 <!-- EDIT648 SECTION "The layout produced by the autorouter is ugly!" [60212-60355] -->
1364 <h1 class="sectionedit649"><a name="gerber_files_prints_and_other_i_o_issues" id="gerber_files_prints_and_other_i_o_issues">Gerber files, prints and other I/O issues</a></h1>
1365 <div class="level1">
1367 </div>
1368 <!-- EDIT649 SECTION "Gerber files, prints and other I/O issues" [60356-60412] -->
1369 <h2 class="sectionedit650"><a name="is_is_possible_to_produce_output_without_gui_intervention" id="is_is_possible_to_produce_output_without_gui_intervention">Is is possible to produce output without GUI intervention?</a></h2>
1370 <div class="level2">
1373 Yes, you can tell pcb on the command line to do an export. All the parameters set in the print dialog can be used in the command line too. Some simple examples:
1374 </p>
1377 Gerber files:
1379 </p>
1380 <pre class="code">pcb -x gerber --gerberfile BOARD BOARD.pcb</pre>
1383 Encapsulated Postscript:
1385 </p>
1386 <pre class="code">pcb -x eps --eps-file BOARD.eps</pre>
1389 Multi page formated Postscript print:
1391 </p>
1392 <pre class="code">pcb -x ps --psfile BOARD.ps BOARD.pcb</pre>
1395 <acronym title="Portable Network Graphics">PNG</acronym> format:
1397 </p>
1398 <pre class="code">pcb -x png --dpi 300 --only-visible --outfile BOARD.png BOARD.pcb</pre>
1401 Different output procedures allow for different options. See the output of <code>pcb --help</code> for details.
1402 </p>
1404 </div>
1405 <!-- EDIT650 SECTION "Is is possible to produce output without GUI intervention?" [60413-61098] -->
1406 <h2 class="sectionedit651"><a name="how_can_i_print_specific_layers_only" id="how_can_i_print_specific_layers_only">How can I print specific layers only?</a></h2>
1407 <div class="level2">
1410 In the <acronym title="Graphical User Interface">GUI</acronym>:
1411 </p>
1412 <pre class="code"># deactivate all layers you don&#039;t want to print
1413 # choose file -&gt; export_layout... -&gt; eps
1414 # check as-shown</pre>
1418 From the command line:
1420 </p>
1421 <pre class="code">pcb -x eps \
1422 --layer-stack &quot;outline,top,silk&quot; \
1423 --as-shown \
1424 --eps-file &quot;foobar.eps&quot; BOARD.pcb</pre>
1428 The layer-stack string can contain a comma separated list of the layers used in the <acronym title="Graphical User Interface">GUI</acronym>. You have to give the option ”–as-shown”. Else, a default layer stack file will be used. In addition there are a number of tokens that are technically no layers like “pins”, or “invisible”. If you put an unknown token in the layer-stack string, pcb responds with a list of known layer names.
1429 </p>
1431 </div>
1432 <!-- EDIT651 SECTION "How can I print specific layers only?" [61099-61797] -->
1433 <h2 class="sectionedit652"><a name="how_can_i_print_the_bottom_side_of_the_board" id="how_can_i_print_the_bottom_side_of_the_board">How can I print the bottom side of the board?</a></h2>
1434 <div class="level2">
1437 From the command line: Add “solderside” to the layer-stack string of the print command. Example:
1439 </p>
1440 <pre class="code"> pcb -x eps --layer-stack &quot;silk,solderside&quot; \
1441 --as-shown \
1442 --eps-file &quot;/tmp/foobar.eps&quot; BOARD.pcb</pre>
1444 </div>
1445 <!-- EDIT652 SECTION "How can I print the bottom side of the board?" [61798-62077] -->
1446 <h2 class="sectionedit653"><a name="how_do_i_make_a_board_outline_to_go_with_my_gerbers_to_the_board_maker" id="how_do_i_make_a_board_outline_to_go_with_my_gerbers_to_the_board_maker">How do I make a board outline to go with my gerbers to the board maker?</a></h2>
1447 <div class="level2">
1450 You can add an outline layer to your pcb projects. PCB interprets any layer called ‘outline’ (edit –&gt; edit name of –&gt; active layer) as though it is the absolute edge of the pcb. PCB prints gerber files that rigidly represent this. Note, that the name of this layer is case sensitive.
1451 </p>
1454 You can enter your outline layer thru PCB’s <acronym title="Graphical User Interface">GUI</acronym>. You just draw the lines of the board outline. You can generate boards of any shape this way.
1455 </p>
1458 It’s also possible to edit the native .pcb file format of your layout. I usually use layer 8 for outlines:
1460 </p>
1461 <pre class="code">Layer(8 &quot;outline&quot;)
1463 Line[x1 y1 x2 y2 1000 2000 0x00000000]
1464 Line[x2 y2 x3 y3 1000 2000 0x00000000]
1465 Line[x3 y3 x4 y4 1000 2000 0x00000000]
1466 Line[x4 y4 x1 y1 1000 2000 0x00000000]
1467 Line[&lt;more points go here for non-square boards&gt; 1000 2000 0x00000000]
1468 )</pre>
1470 </div>
1471 <!-- EDIT653 SECTION "How do I make a board outline to go with my gerbers to the board maker?" [62078-62980] -->
1472 <h2 class="sectionedit654"><a name="how_do_i_make_sure_that_the_design_contains_only_certain_hole_sizes" id="how_do_i_make_sure_that_the_design_contains_only_certain_hole_sizes">How do I make sure, that the design contains only certain hole sizes?</a></h2>
1473 <div class="level2">
1476 Some fabs provide lists of standard drill sizes and charge extra if the design contains additional sizes. You can put this list in a “vendor resource file”. This file may also exceptions and specify if the nearest diameter should be chosen, or rounded up to the next size in the list. See <a href="http://pcb.gpleda.org/pcb-cvs/pcb.html#Vendor-drill-mapping" class="urlextern" title="http://pcb.gpleda.org/pcb-cvs/pcb.html#Vendor-drill-mapping" rel="nofollow">the section Vendor-drill-mapping</a> in the pcb manual for the syntax of this file.
1477 </p>
1480 Load the file to pcb with Load-Vendor-Resource-File from the main menu. Alternatively, you can use with the command :LoadVendor(drillfile). Substitute “drillfile” with the name of your file.
1481 </p>
1484 On load, pcb will substitute drill sizes so that the layout conforms to the list. If you want to apply an already loaded vendor resource file again, you can do Apply-vendor-drill-mapping from the connects menu.
1485 </p>
1487 </div>
1488 <!-- EDIT654 SECTION "How do I make sure, that the design contains only certain hole sizes?" [62981-63952] -->
1489 <h2 class="sectionedit655"><a name="i_m_done_with_my_layout_how_should_i_check_my_design" id="i_m_done_with_my_layout_how_should_i_check_my_design">I&#039;m done with my layout. How should I check my design?</a></h2>
1490 <div class="level2">
1491 <ul>
1492 <li class="level1"><div class="li"> Run a check of design rules either through the command interface (“DRC()”) or from the menu (Connects - Design Rule Checker). You can set the rules in the sizes section of the preference dialog. Results of the check are shown in the log window. </div>
1493 </li>
1494 </ul>
1497 Besides running the DRC checker, it is essential to check your Gerber files. The gEDA Suite includes the program “gerbv” for this task. Here are some things to check/verify:
1498 </p>
1499 <ul>
1500 <li class="level1"><div class="li"> Check that all trace widths are the correct size. Also make sure your trace widths and metal-metal separations are above the minimum specified by your PCB vendor.</div>
1501 </li>
1502 <li class="level1"><div class="li"> Check that all hole diameters are called out at the correct size.</div>
1503 </li>
1504 <li class="level1"><div class="li"> Check that metal annular rings around holes/vias are large enough. The annular ring is the distance between the hole’s edge and the outer diameter of the metallization. The annular ring must be large enough to accomodate drill location + layer registration + other manufacturing inaccuracy. This information should be available from your PCB fabrication house; they normally publish the minimum annular ring requirements in their manufacturing rules document.</div>
1505 </li>
1506 <li class="level1"><div class="li"> Check that your antipads (clearance around holes/vias) are large enough. This information should be available from your PCB fabrication house; ask them for their manufacturing rules document.</div>
1507 </li>
1508 <li class="level1"><div class="li"> Verify that no soldermask or silkscreen overlays a copper pad or through-hole.</div>
1509 </li>
1510 <li class="level1"><div class="li"> On plane layers, verify that at least some vias connect to it (yes, I have seen a board where the entire ground plane was floating – not done in pcb btw)</div>
1511 </li>
1512 <li class="level1"><div class="li"> On plane layers, verify that at least some vias _don’t_ connect to it.</div>
1513 </li>
1514 <li class="level1"><div class="li"> Do a visual sanity check of all layers. Nothing detailed, just does it look approximately like you think it should.</div>
1515 </li>
1516 <li class="level1"><div class="li"> Are all layers negative/positive as they should be? Note that some fab houses want positive layers only. PCB will automatically create negative Gerbers on outer layer planes with no tracks. If you want an all-plane layer to be output as a positive layer, draw a single track somewhere in an unused part of the plane. This will trigger PCB to render that layer as a positive layer.</div>
1517 </li>
1518 </ul>
1520 </div>
1521 <!-- EDIT655 SECTION "I'm done with my layout. How should I check my design?" [63953-66172] -->
1522 <h1 class="sectionedit656"><a name="exporting_other_formatsraster_and_ps_files" id="exporting_other_formatsraster_and_ps_files">Exporting Other Formats: Raster and PS Files</a></h1>
1523 <div class="level1">
1525 </div>
1526 <!-- EDIT656 SECTION "Exporting Other Formats: Raster and PS Files" [66173-66232] -->
1527 <h2 class="sectionedit657"><a name="what_is_xy-max_in_the_png_export_dialog_box" id="what_is_xy-max_in_the_png_export_dialog_box">What is xy-max in the PNG export dialog box?</a></h2>
1528 <div class="level2">
1531 It limits the size of the image to NxN pixels, but maintains the aspect ratio. For example, if you set it to 400, a 6000&times;8000 mil board would yield a 300&times;400 image, but a 6000&times;4500 board yeilds a 400&times;300 image.
1532 </p>
1534 </div>
1535 <!-- EDIT657 SECTION "What is xy-max in the PNG export dialog box?" [66233-66503] -->
1536 <h1 class="sectionedit658"><a name="customization" id="customization">Customization</a></h1>
1537 <div class="level1">
1539 </div>
1540 <!-- EDIT658 SECTION "Customization" [66504-66532] -->
1541 <h2 class="sectionedit659"><a name="i_don_t_like_that_old-style_black_background_how_can_i_get_a_light_canvas" id="i_don_t_like_that_old-style_black_background_how_can_i_get_a_light_canvas">I don&#039;t like that old-style black background. How can I get a light canvas?</a></h2>
1542 <div class="level2">
1545 In <a href="geda-glossary.html" class="wikilink1" title="geda-glossary.html">GTK-HID</a> there is a preference dialog in the file menu. The Colors tab presents a convinient way to set all the colros pcb uses via the standard GTK color chooser. The colors are saved to $HOME/.pcb/preferences on shut down of the application.
1546 With <a href="geda-glossary.html" class="wikilink1" title="geda-glossary.html">Lesstif-HID</a> there is no preference dialog. Colors can be set in <code>$HOME/.pcb/settings</code>
1547 </p>
1549 </div>
1550 <!-- EDIT659 SECTION "I don't like that old-style black background. How can I get a light canvas?" [66533-66987] -->
1551 <h2 class="sectionedit660"><a name="how_do_i_set_the_default_values_of_the_postscript_dialog" id="how_do_i_set_the_default_values_of_the_postscript_dialog">How do I set the default values of the postscript dialog?</a></h2>
1552 <div class="level2">
1555 You can set the default options of the postscript printing dialog as command line parameters when invoking pcb. Type <code>pcb –help</code> for a list of available options. These options can also be set in a file <code>$HOME/.pcb/settings</code>. A settings file for a4 paper, no alignment marks, multi page output would contain:
1557 </p>
1558 <pre class="code">media = A4
1559 align-marks = 0
1560 multi-file = 1</pre>
1562 </div>
1563 <!-- EDIT660 SECTION "How do I set the default values of the postscript dialog?" [66988-67426] -->
1564 <h2 class="sectionedit661"><a name="how_do_i_customize_the_mouse_behavior" id="how_do_i_customize_the_mouse_behavior">How do I customize the mouse behavior?</a></h2>
1565 <div class="level2">
1568 There is no <acronym title="Graphical User Interface">GUI</acronym> way to modify the mouse behavior. However, you can adapt it to your needs without recompiling. This is how:
1569 </p>
1570 <ol>
1571 <li class="level1"><div class="li"> locate the file <code>gpcb-menu.res</code> on your box. For lesstif there is a similar file called <code>pcb-menu.res</code> </div>
1572 </li>
1573 <li class="level1"><div class="li"> copy the file to <code>$HOME/.pcb</code></div>
1574 </li>
1575 <li class="level1"><div class="li"> edit to your needs, save</div>
1576 </li>
1577 <li class="level1"><div class="li"> on start-up, pcb will read this localised copy. This will overwrite whatever settings were made by the system gpcb-menu.res</div>
1578 </li>
1579 </ol>
1581 </div>
1582 <!-- EDIT661 SECTION "How do I customize the mouse behavior?" [67427-67907] -->
1583 <h2 class="sectionedit662"><a name="how_do_i_temporarily_change_keyboard_shortcuts" id="how_do_i_temporarily_change_keyboard_shortcuts">How do I temporarily change keyboard shortcuts?</a></h2>
1584 <div class="level2">
1587 The GTK version of pcb includes a neat way to change shortcuts on the fly:
1588 </p>
1589 <ul>
1590 <li class="level1"><div class="li"> go to the menu and let the mouse hover over the item to be configured. Don&#039;t press any mouse button.</div>
1591 </li>
1592 <li class="level1"><div class="li"> type whatever shortcut you&#039;d like to assign to the item under the mouse.</div>
1593 </li>
1594 <li class="level1"><div class="li"> the shortcut will be working immediately. Conflicts with other shortcuts will be resolved by removing the shortcut of the conflicting definition.</div>
1595 </li>
1596 </ul>
1599 This setting will be reset at the next session of pcb.
1600 </p>
1602 </div>
1603 <!-- EDIT662 SECTION "How do I temporarily change keyboard shortcuts?" [67908-68431] -->
1604 <h2 class="sectionedit663"><a name="how_do_i_permanently_change_keyboard_shortcuts" id="how_do_i_permanently_change_keyboard_shortcuts">How do I permanently change keyboard shortcuts?</a></h2>
1605 <div class="level2">
1608 Default keyboard shortcuts are defined in files called <code>gpcb-menu.res</code> if you use the default GTK interface. On start-up pcb reads the configuration from a system path, e.g. <code>/usr/local/share</code> or <code>/usr/share/</code>. For permanent change of keyboard shortcuts you can copy the system file to <code>$HOME/.pcb/gpcb-menu.res</code> and edit to your needs. Settings in this file will overwrite the system configuration.
1609 </p>
1612 The lesstif interface reads <code>pcb-menu.res</code> files instead.
1613 </p>
1615 </div>
1616 <!-- EDIT663 SECTION "How do I permanently change keyboard shortcuts?" [68432-68960] -->
1617 <h2 class="sectionedit664"><a name="can_i_customize_the_menu" id="can_i_customize_the_menu">Can I customize the menu?</a></h2>
1618 <div class="level2">
1621 The menu is defined in <code>gpcb-menu.res</code> for the GTK-UI. You can place a localized copy in <code>$HOME/.pcb/</code>. See the notes above on configuration of keyboard shortcuts and mouse behavior.
1622 </p>
1624 </div>
1625 <!-- EDIT664 SECTION "Can I customize the menu?" [68961-69187] -->
1626 <h1 class="sectionedit665"><a name="you_didn_t_answer_my_question_what_other_resources_exist_for_pcb_information" id="you_didn_t_answer_my_question_what_other_resources_exist_for_pcb_information">You didn&#039;t answer my question. What other resources exist for PCB information?</a></h1>
1627 <div class="level1">
1628 <ul>
1629 <li class="level1"><div class="li"> <a href="http://pcb.gpleda.org/pcb-cvs/pcb.html" class="urlextern" title="http://pcb.gpleda.org/pcb-cvs/pcb.html" rel="nofollow">the pcb manual</a></div>
1630 </li>
1631 <li class="level1"><div class="li"> <a href="http://www.luciani.org/geda/pcb/faq-pcb-footprint.html" class="urlextern" title="http://www.luciani.org/geda/pcb/faq-pcb-footprint.html" rel="nofollow">http://www.luciani.org/geda/pcb/faq-pcb-footprint.html</a></div>
1632 </li>
1633 <li class="level1"><div class="li"> <a href="http://pcb.gpleda.org/faq.html" class="urlextern" title="http://pcb.gpleda.org/faq.html" rel="nofollow">http://pcb.gpleda.org/faq.html</a></div>
1634 </li>
1635 </ul>
1639 You can get fast responses from the geda-user email list. If you haven’t found an answer to your question about PCB on this page, or in the other documentation, then post to the list! Note that you must subscribe to the geda-user e-mail list before you can post to the list. The gEDA e-mail lists, and their archives, are at: <a href="http://geda.seul.org/mailinglist/index.html" class="urlextern" title="http://geda.seul.org/mailinglist/index.html" rel="nofollow">http://geda.seul.org/mailinglist/index.html</a>
1641 </p>
1643 </div>
1644 <!-- EDIT665 SECTION "You didn't answer my question. What other resources exist for PCB information?" [69188-] --></body>
1645 </html>