Re: gEDA-user: Newbie PCB DRC questions
Ah, my mistake then. Maybe they were auto routed segments I'd ripped up and manually routed. Apologies for the unwarranted slur on the auto router. I don't believe these small segments are due to the autoroute process. I see them a lot and I've never used the auto-router. I believe they can occur when: You add a line containing several segments with snap to pins and pads turned on. This can put a short ( 1 grid long) segment in the line. ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
Re: gEDA-user: Newbie PCB DRC questions
Peter, I don't believe these small segments are due to the autoroute process. I see them a lot and I've never used the auto-router. I believe they can occur when: You add a line containing several segments with snap to pins and pads turned on. This can put a short ( 1 grid long) segment in the line. Then if you move or delete one of the longer line segments attached to short segment the short segment can be left behind. If it is under a pad or via, it is of little consequence to the photoplotter, but is still seen by the DRC. Sometimes moving a segment next to an off-grid segment like this will make a mess as it moves the line segment on the far side of the short segment. (This appears to be an issue caused by the vertex selection code - see the mailing list archives [http://archives.seul.org/geda/user/Jun-2006/msg00058.html] where this was brought up a few months ago.) As you've found, turning off pads and or vias, and drawing with line filling off can let you see these hidden features and delete them. Joe Peter Baxendale wrote: 3. Sometimes when DRC reports copper areas too close, I go to the coordinates specified in the message and I cannot for the life of me find anything closer than 10 mils. (And I still have it checking for 5 mil spacings.) Does DRC sometimes get fooled into thinking that connected lines should be separated? Or am I misinterpreting the errors? I've seen similar things with auto routed tracks. Sometimes, if I zoom right in and play about with layer visibility a bit I can see a very small piece of track under/over a via. Deleting this makes the drc error go away. I assume these bits of track are some kind of artifacts of the auto route process. I don't know why this should produce that particular error. ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
Re: gEDA-user: Newbie PCB DRC questions
On Oct 3, 2006, at 8:32 PM, John Griessen wrote: I think the way some of these come into being is faster-than-the- eye-can-see action sorta-like contact bounce, but it's mouse- contact-bounce. Sounds like a deviant kind of ball game. But really, who knows? ?quien sabe? como estan mouse bounce... And then there are all those messy remains -- some swept under the via rugs...hiding there. Hmm, I see I'm not the only one who's drinking tonight. ;) -Dave -- Dave McGuire Cape Coral, FL ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
gEDA-user: Newbie PCB DRC questions
Hello everyone: I've been checking my board layout with the Design Rule Checker command in PCB. I was encountering some mysterious behavior and wondering if anybody could explain this a little. 1. The default minimum spacing is 10 mils, yet DRC flags everything that is exactly 10 mils. This is a problem because the auto-router put traces 10 mils apart in many places. I tried changing the minimum spacing to 9.9 or 9, but apparently that's not valid because it does not retain that value. (In fact, the preferences dialog experiences an error if I do this, and refuses to close the second time I bring it up.) So I set the min-spacing to 5 mils and DRC found a few problems in the lines I'd added manually, which I was able to correct. Does this mean the actual minimum spacing should be 15 mils or something like that, so that auto-routed traces will pass the DRC 10 mil guideline? 2. I've been seeing potential for broken trace error a lot. In some cases I can see that a line has some unnecessary jags in it which I've then straightened out. In other cases the only problem seems to be that two connecting lines that go in the same direction have for some reason not been merged into a single line. It's my understanding that if the trace _looks_ continuous (at a pretty high zoom) it _is_ continuous. Is DRC flagging nonexistent errors here or is my understanding incorrect? 3. Sometimes when DRC reports copper areas too close, I go to the coordinates specified in the message and I cannot for the life of me find anything closer than 10 mils. (And I still have it checking for 5 mil spacings.) Does DRC sometimes get fooled into thinking that connected lines should be separated? Or am I misinterpreting the errors? Thanks! Vaughn T ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
