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GND plane

bdoubleu

I try to make a ground plane like in this video   https://youtu.be/CCTs0mNXY24?t=691  and I get it to make the plane fine.  I hit the ratsnest button and you can see the little lines connect my ground stuff to the plane, and it also shows the clearances and stuff around components like this video show.  but here's where the problem comes in.  If I auto route, I get no traces to the components... if I go delete all the work from the ground plane and auto route it routes just fine and it connects all the grounded components through this long and winding traces... so why won't it route with the ground plane... seems like that would be easier... am I missing a setting that allow it to route around and through this ground plane?  what gives?

 

EDIT:  Since I did not get any replies, I set the video to the time of when the ground plane is being made....so you don't have to watch the whole video to see what I'm getting at.  If you don't want to watch the video, basically, I draw a polygon, then rename it as GND (same as my grounds) and it makes the whole board a ground plane, then I ratsnest and autoroute and it won't autoroute anything... if I remove/undo the ground plane it autoroutes fine and connects a long ground trace to all of my grounds.  I supposed I don't have to have the ground plane but thought it would be nice.

 

thoughts?  note that I'm a rookie at this.. and this board is for educational purposes for my 12 year old son... trying to get him interested in programming and engineering.

  • 0

    well i think i got it... i changed the "effort" from low to high and it actually put traces down on the board.... so not sure why low wouldn't do it... don't even know what that setting does other than the obvious...

  • 0 in reply to bdoubleu

    On 26/08/15 01:17, Brandon Wilson wrote:

    well i think i got it... i changed the "effort" from low to high and it

    actually put traces down on the board.... so not sure why low wouldn't

    do it... don't even know what that setting does other than the

    obvious...

     

    I'm not a user of autorouting - it always produces bad layouts that take

    longer to fix than I would take routing by hand - but it seems to me

    that there would be occasions when you want to "have a go" at routing

    new airwires without major disruption of what's already there. If that

    fails, you may choose to manually help it along, rather than letting it

    randomly rip up everything until it hits on a poor solution. That could,

    I suppose, be described as "have a go but don't put much effort into

    it", so the "effort" setting could be for that.

     

    What you did by filling the ground plane before routing, was to block

    all the possible routes it could take. Then, by asking it not to put in

    much effort, you set an impossible task, which it failed at. Allowing

    more effort lets it rip up your ground plane to find a route.

     

    Now somebody who's actually used the autorouter will come along and

    correct all my misunderstandings.

     

     

  • 0 in reply to bdoubleu

    Am 26.08.2015 um 02:17 schrieb Brandon Wilson:

    well i think i got it... i changed the "effort" from low to high and it

    actually put traces down on the board.... so not sure why low wouldn't

    do it... don't even know what that setting does other than the

    obvious...

     

    --

    To view any images and attachments in this post, visit:

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    I suppose that the routing grid was too coarse and the Autorouter

    could not connect to the pads. With the change of "effort" EAGLE

    created more routing jobs and I assume that there were also

    different grid settings used. So this could be the reason why

    it workled then.

     

    Basically I'ld recommend to check the grid settings in the jobs.

    Therefore click onto th >> button and look into the parameters.

     

    How the get an idea of a fitting grid? Look into your layout

    and check the smallest or fine-pitched components. Display the grid

    and play around with the settings. Best is, if each pad has

    a centered grid line and at leat one between adjacent pads.

    If the compnent is not placed on the grid exactly, use Ctrl + MOVE

    to bring it into the current grid

     

    Hope this helps.

     

    --

    Mit freundlichen Gruessen / Best regards

    Richard Hammerl

      CadSoft Support -- hotline@cadsoft.de

      FAQ: http://www.cadsoft.de/training/faq/

     

  • 0 in reply to autodeskguest

    thank you for the extra input.  I have definitely read that more advanced users of Eagle CAD do not auto route, to have more control of what signals go where.  I will likely getting into manually routing a board here soon.

     

    an additional question... along the lines of auto routing, what would be the method to the madness if I wanted to do a simple two layer board like this, put the ground plane in on both sides, then manually route.  I haven't tried this yet, but I would assume I put the ground plane in like I did before, then just start putting down traces and it will remove the ground plane as necessary?  or is there something else I would want to do?

     

    tonight we will be trying to print off the top and bottom layers to make sure the auto router algorithm at least connected everything properly...  stay tuned.

  • 0 in reply to bdoubleu

    Am 26.08.2015 um 16:31 schrieb Brandon Wilson:

    thank you for the extra input.  I have definitely read that more

    advanced users of Eagle CAD do not auto route, to have more control of

    what signals go where.  I will likely getting into manually routing a

    board here soon.

     

    an additional question... along the lines of auto routing, what would be

    the method to the madness if I wanted to do a simple two layer board

    like this, put the ground plane in on both sides, then manually route.

    I haven't tried this yet, but I would assume I put the ground plane in

    like I did before, then just start putting down traces and it will

    remove the ground plane as necessary?  or is there something else I

    would want to do?

     

    tonight we will be trying to print off the top and bottom layers to make

    sure the auto router algorithm at least connected everything

    properly...  stay tuned.

     

    --

    To view any images and attachments in this post, visit:

    http://www.element14.com/community/message/158740

     

     

     

    I would suggest to route first and then define the ground planes.

    If you use RATSNEST in order to recaculate the airwires while routing

    for example, the polygons will be calculated and filled as well.

    So you have to rip them up each time. I you leave the polygons

    calculated it's hard to recongnize where you can route...

     

     

    --

    Mit freundlichen Gruessen / Best regards

    Richard Hammerl

      CadSoft Support -- hotline@cadsoft.de

      FAQ: http://www.cadsoft.de/training/faq/