kicad-developers team mailing list archive

[Tomasz Wlostowski <tomasz.wlostowski@xxxxxxx>]

On 14.12.2015 14:40, Strontium wrote:
> Hi Thomas,
> 
> I considered this, but tracking zones is non trivial.
> 
> For example, imagine the stackup:
> 
> GND
> VCC
> GND
> VCC
> 
> A Through Via, from top to bottom could be connected validly connected
> to either GND or VCC.
> 
> Once the net is removed from the via by the reassignment pass, there is
> no longer any information left to tell kicad which pair of zones was
> connected by the via.

Indeed, in case of such a conflict retaining the via's net is IMHO the
only good solution.

> 
> The approach I suggest will fix this problem, because it just wont
> change the net for those vias.  It wont consider if there is a zone or
> not, it just says "hey, you gave it the GND net, so i will leave it as
> GND."

It also seems Altium is managing via's nets this way. I would vote for
merging the patch.

Cheers,
Tom

> 
> 
> On 14/12/15 21:21, Tomasz Wlostowski wrote:
>> On 12.12.2015 02:41, Strontium wrote:
>>> This change should not break or modify any current behaviour, EXCEPT to
>>> retain the nets of tracks/vias which Kicad is otherwise incapable of
>>> determining automatically.
>> Hi Steven,
>>
>> Thanks for the patch, it also (partially) fixes the via stitching issue
>> many people have been complaining about. The origin of the problem is
>> that the net propagation code does not take zones into account - so a
>> via that is not connected to any pad with a chain of tracks is treated
>> as disconnected.
>>
>> Adding zone support in the net calculation code should AFAIK fix this
>> for good, but it may also require enhancing the DRC (so that it will
>> report every object with no pad connection) and the 'clean tracks&vias'
>> tool code.
>>
>> Regards,
>> Tom
>>
>