Re: gEDA-user: Light vs heavy gschem symbols?

[John Doty <jpd@xxxxxxxxxxxxx>]

John Dozsa wrote:

> It seems to me that the concept of a "release library" and a
> "development library" could support both the newbies and the more
> experience user that wants more freedom.  The newbie would be directed
> to use "release library" symbols with specific footprint attributes and
> the experienced user could do his own with "development library" parts.

The problem is that this doesn't scale to multiple organizations working
on wildly different *kinds* of projects. A standard "heavy" library would
need billions of symbols to be useful. There are too many options.

What I now do in gEDA (and used to do in Viewlogic) is to create a library
of symbols that corresponds to the parts stock that is to be procured and
used for a project or a related set of projects. A "heavy" symbol library
is thus an abstract representation of a stockroom. I'll start with the
standard "light" library symbols, copy them as needed to the project
library, and then add the required attributes. Often I'll include a .txt
file with a brief description of how requirements led to the part
specification (useful when a substitute must be found).

The only other practical solution I can see is inheritance. Something
like:

TL07X-1.sym inherits graphics and pinorder from opamp-1.sym, adds a SPICE
model.

TL072-1.sym inherits the above from TL07X-1.sym and inherits slotting from
8_pin_dual_opamp.sym (which has no graphic).

TL072CP-1.sym inherits from TL072-1.sym, adds a footprint.

etc.

John Doty          Noqsi Aerospace Ltd.