kicad-developers team mailing list archive

[Wayne Stambaugh <stambaughw@xxxxxxxxx>]

On 5/4/2016 4:11 PM, Tomasz Wlostowski wrote:
> On 04.05.2016 16:48, Wayne Stambaugh wrote:
>> How are you saving this auto generate flag and width/length parameters
>> in the schematic?  If you are using component fields or text that's
>> fine.  However, please keep in mind that using component fields and text
>> is for passing information to third party tools that are not part of
>> kicad.  If we are going to support net ties and micro wave component
>> generation, we should do that as part of KiCad proper rather than treat
>> it like a third party tool which you are proposing. 
> 
> Hi Wayne,
> 
> I would store the microwave dimensions as key:value pairs, just like the
> current schematic fields. I think microwave components will be best
> handled by python scripting. These scripts should be IMHO permanently
> included in Kicad distribution, not a 3rd party tool. I chose component
> fields to pass the dimensions information because with every new exotic
> shape (e.g. a Wilkinson power divider instead of a simple microstrip
> line), we would need to add new tokens to the SCH file format and
> netlist specification.

Hey Tom,

Would it be easier to provide a python script with a UI to input the
dimensional information used to generate these complex microwave
footprints and just associate them with a schematic symbol rather that
trying to squeeze all of that dimensional information into a field?
This may be more natural for the user to handle.  I understand the
temptation to use fields to do this but I'm not sure this is the easiest
path for users.  I just don't see users be comfortable with this in
terms of usability.  Developers will have no issues with it but I'm
trying to see this from a typical user's point of view.  It might be
worth getting some feedback on the users forum.

> 
> For net ties, there's no schematic/netlist format changes, only PCB.
> 
> I'm wondering how to handle the auto_generate flag. Maybe this one
> justifies a separate file format entity connected to a checkbox in the
> sch library editor and a text field specifying which plugin/script to run...

The only risk I see with using a field as an auto_generate flag is field
namespace pollution.  If someone inadvertently uses the auto_generate
field name, I image a bunch of script errors would be a bit confusing.
This risk is low but it is something to consider.  My proposal would
eliminate the need for an auto_generate flag.

> 
>> I don't want the
>> component fields and text used for kicad features.  If you want to
>> provide this as an interim solution, I am OK with that.  However, you
>> may be creating more work for yourself when we finally get around to
>> supporting net ties and micro wave component generation as part of the
>> schematic editor. 
> 
> How do you see the role of the schematic editor in generation of
> microwave components (in my proposal there's none)?

I agree.  I don't pretend to be a microwave expert but AFAIK most if not
all microwave features are complex geometrical shapes which should be
treated as footprints and associated with a schematic symbol.  I don't
see why the schematic editor would need to know anything about microwave
footprints other than possibly passing parametric information via a
field to the board editor.

> 
> Cheers,
> Tom
>