-------------------------------------------- On Mon, 9/2/13, Brian Sidebotham <[email protected]> wrote:
Subject: Re: [Kicad-developers] Experiments and considerations for more layer To: "Kicad Developers" <[email protected]> Date: Monday, September 2, 2013, 5:30 PM On 2 September 2013 10:02, Lorenzo Marcantonio <[email protected]> wrote: At last I tried to broke the 32 layer barrier in pcbnew. Needed the assembly and courtyard on both sides, so the ECO are not enough. Also they need to be flippable, too. Result: succesful, learnt things that could be useful later. [snip] -- Lorenzo Marcantonio Logos Srl Hi Lorenzo, I could really do with more layers too. Although when I say *more* layers, I mean that I could really do with dedicated assembly and courtyard layers. The assembly layer needs the reference field on, as you say, at the insertion point of the component as well as a physical bounding box; This should flip when the component is flipped. Thanks for spending the time investigating it, because I'll sure be glad of any work that goes into supporting these layers. Best Regards, Brian. ===== While we're on the topic of layers, is anyone interested in IDF3.0 import/export? I was thinking of implementing it since I'll have a little free time in the next few months. If I implement it I'd like to draw regions on a top and bottom 'mechanical keepout' layer. Alternatively I guess I could create a hatched region or some such on the silk layers but I'd rather not pollute the silks. The IDF specification allows TOP, BOTTOM, or BOTH specifications for the keepout; there is also a height (0 = absolutely nothing can go there, >0 means max. height of components) but I don't see how height restrictions can be supported in KiCAD nor is it the responsibility of the ECAD to handle this. I see the mech. keepout as merely a reminder to the layout designer that there are mechanical restrictions within certain regions; it is the responsibility of the mechanical drafter to provide all relevant information in other documents. Using IDF also gives us another method of specifying the board outline, but to be honest the specification has severe defects; for example, arcs are not correctly constrained so for any arc specified in IDF there are 4 different ways to draw the arc if we assume a circular arc; for elliptical arcs there are an infinite number of ways to draw the arc and every single one will conform to the standard as written. Nice work Lorenzo. As for how many layers we can ultimately use, I imagine at least twice as many as the copper layers in a pathological case thanks to things like 'no route' areas underneath ICs. But with 64 layers total I think we'll be safe for a long time. - Cirilo _______________________________________________ Mailing list: https://launchpad.net/~kicad-developers Post to : [email protected] Unsubscribe : https://launchpad.net/~kicad-developers More help : https://help.launchpad.net/ListHelp
