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.
Dick
