Re: gEDA: Simple text attached to pins allowed?

[Stephen Meier <smeier-at-NOSPAMAlchemyResearch_dot_com>]

 From a parsing standpoint ambiguities are bad very very very bad... So 
i think only deffined attributes should be allowed. Adding new 
definitions is very easy...now I feal like Dr Sues... very very very 
easy. (if the gate don't flop go ask your pop)

in system-gschemrc in the attribute-name section

add a line like

(attribute-name "eatmyshorts")

Now I wonder what Vref used to do (was ment to do)? I know for a number 
of pecl devices they have output pins that provide a reference voltage. 
The MC10EL32 pin 4 is labbled as Vbb where Vbb is a reference voltage 
output that is between 3.65 and 3.75 v at 25 degrees C. Logic High in 
should be greater then 3.87 V Logic Low in should be lower then 3.52 V. 
SO it looks like the reference voltage is a good comparitor voltage to 
differentiate the logic levels.

Steve Meier


p.s. I think when i have lots and lots of free time i will rewrite the 
documentation in Dr Sues fassion.



Stuart Brorson wrote:

>Guys --
>
>I recently came across some symbols with strange pin syntax which made
>gattrib segfault.  I have fixed gattrib to be robust against this
>syntax, but I am now wondering if the syntax is valid or not. 
>
>Pins can have attribs attached to them.  Here is an example pin with
>attribs:
>
>P 300 4200 0 4200 1 0 1
>{
>T 136 4250 5 8 1 1 0 0 1
>pinnumber=1
>T 136 4250 5 8 0 0 0 0 1
>pinseq=1
>}
>
>On certain symbols I have found pins with simple text also attached.
>For example, here is a snippet of analog/CS5396-1.sym:
>
>P 300 4200 0 4200 1 0 1
>{
>T 136 4250 5 8 1 1 0 0 1
>pinnumber=1
>T 136 4250 5 8 0 0 0 0 1
>pinseq=1
>T 375 4150 3 8 1 0 0 0 1
>Vref
>}
>
>It has text "Vref" attached to the pin.  Is this valid?
>
>Many other symbols have this construct also.
>
>More generally, is this syntax a good idea?  That is, doing this means
>that pins can be complexes, or at least have "primitive objects"
>besides attributes.  Does this serve a purpose?  I was under the
>impression that "primitive objects" only made sense for complexes
>(components).  
>
>If it were me, I would say that pins may only have valid attribs
>attached, and nothing else.  But I might be wrong.  Is there ever a
>time that pins would need to have anything more than attributes
>attached?
>
>Stuart
>
>  
>