← Back to team overview

kicad-developers team mailing list archive

Re: PCB Layer Stackup UI


Dick Hollenbeck a écrit :

jean-pierre. charras@gipsa- lab.inpg. fr <mailto:jean-pierre.charras%40gipsa-lab.inpg.fr> wrote:
> Dick Hollenbeck a écrit :
>> jean-pierre. charras@gipsa- lab.inpg. fr
>> <mailto:jean- pierre.charras% 40gipsa-lab. inpg.fr> wrote:
>>> Dick Hollenbeck a écrit :
>>>> I meant to say specctra syntax, not specctra format. There is no
>>>> specctra format that can fully describe a board. Briefly, there is the
>>>> DSN format and the SES format. The DSN describes the copper layers
>>>> only, no technical layers. No text. The SES format describes a subset
>>>> of the copper layers and has less information in it.
>>> I did not understood that.
>>> So, I do not see any problem to use the Specctra syntax.
>> One or more sample board files should be created then before any coding
>> is done IMO, using a text editor and a brain.
> Ok. I have already a text editor.
>> I think this process is easiest to create the sample(s):
>> 1) load a DSN file from the specctra_export into a text editor or have
>> it as a hardcopy printout nearby for reference.
>> 2) load an existing board file, one with multiple layers, components,
>> tracks, vias, drawings, and multiple zones.
>> 3) copy the board file to a new window, and convert it to the new
>> syntax, but incorporate some new concepts. This is an object
>> conversion, not so much a line by line conversion.
>> New concepts in the file:
>> ** Special layer names. Any technical layers, plus front and back
>> copper, should get fixed names rather than layer numbers
>> ** Layer sets as discussed.
>> ** unit_res see this in the specctra spec, it allows different regions
>> in the file to to have different units. each unit_res has a limited
>> scope of applicability.
>> ** use concise element names, pay attention to frequency of use. no
>> element should have a lot of unnamed parameters, but instead use nested
>> elements to make the file self documenting.
>> ** the first copper layer is number 0 but has a special name 'front', in
>> addition to any name the user gives it.
> We also can use keywords instead of numbers like in Gencad format (see
> export_gencad. cpp)
> layer identification use TOP, BOTTOM, INNER1, INNER2, SOLDERPASTE_ TOP ...
> and no numbers.

Yes, but I wonder if you are reading my posts.

lower case only.

UI will be using the terms front and back. So to introduce TOP and
BOTTOM is silly.

> So use 0 for the first copper or the last or negative values for non
> copper layers or disabled layers ... is just a coding design
> and does not appears in files.

The copper layer number are indices into the layer definition block.
Specctra does this, to replicate a copper layer name everywhere there is
a layer will balloon the file size. To use a fixed copper layer name
for internals is silly.


Mails take some time to be received, they have a latency time.
My mail was sent before i received your mail.

TOP and others key words are just what GenCad uses, not what I want to use.
See what other guys made is always interesting:
- If this is a good idea remember it.
- If this is a bad idea, just not not use it.

Jean-Pierre CHARRAS

Maître de conférences
Directeur d'études 2ieme année.
Génie Electrique et Informatique Industrielle 2
Institut Universitaire de Technologie 1 de Grenoble
BP 67, 38402 St Martin d'Heres Cedex

Recherche :
Rue de la Houille Blanche
38400 Saint Martin d'Heres

Follow ups