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Re: gEDA-user: weird names in PCB part library
Here is my take on the pcb libraries; it basically agrees with Steve's.
I personally do not know the ins and outs of M4 - I know just
enough to toy with the M4 based libraries. That does not mean that
M4 is bad, but I agree that *users* of pcb should not need to know M4.
Surprise! They don't. That's why I wrote the new style libraries, so nobody
would be *required* to write M4 macros, including me. That I did not
gut the M4 macro libraries from pcb was a good thing. Eventually it will be
possible to remove them (at least to a separate tool folder), but anyone can
safely ignore them now. I marked them all with ~ because many of the
old library parts are just plain wrong and I want to avoid having any bad
elements appear in the new libraries. Even so, the old libraries were very
useful and it would have been a huge penalty to pcb to remove them
and I had no chance of having the time and energy to validate the good ones.
So they are still there. To the extent that keeps people from using pcb,
really the fault of poor documentation. That's partly my fault too, but time
hard to find. You see I have 3 jobs and that doesn't include pcb
teaching evening graduate school, and consulting). I really, really hope to
an actual manual from scratch some day but it keeps getting put off.
What needs to happen is to build an extensive library of known good land
patterns. That's a lot harder than it sounds. I've previously proposed that
a separate project on sourceforge be created specifically for pcb
There are many troubles to overcome in this approach, but I think it is the
best approach. Simply figuring out a workable organization of them is
going to be tough. Unfortunately I don't have the time to administer such
a project; I can barely keep up with pcb coding.
To specifically answer Karel's question on e,b,c pin labeling: it's funny I
changed the 2N3904 to an E,B,C style pin numbering when I first introduced
alpha-numeric pin numbering. But I got so many complaints that I changed it
back to numeric. What I recommend is that you do this: find a good TO92
package in the library (my recollection is that the "standard" M4 based one
runs the silkscreen right across the pads so that's not good), then save it
a file, then edit that file and change the pin numbers to the desired
and put that file into the new library.