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Re: gEDA-user: European symbols?

Johnny Rosenberg wrote:

> here's a  
> new try, which I tested several times:
> http://ubuntuone.com/p/W8l/

I just looked at 7400-IEC-1.sym. Some comments:

* some lines of invisible text is not on 100 grid. 

* the footprint attribute is invisible

* pin labels are invisible

* if pin labels were visible, they'd collide with the box

* pin length is 200 units. IMHO, these lengthy pins result in 
awkward artwork, when there is little space on the canvas. This
is of course a matter of taste.

* the slot attribute is invisible. I like to make it visible, so 
it is explicitly shown on the schematic and can be edited on mouse

* there is no value attribute --> this attribute is used in the bill of 

* the visible string 7400 is simple text. That way, it cannot be edited 
in the schematic. In a real circuit it should read 74HC00 or whatever 
flavor of TTL logic should be used.

* the supply nets are implicitly given with the net attribute. IMHO, 
this approach hides information that should be visible in the 
schematic. I prefer to put the power pins in a dedicated 74er 
power symbol.

* suggestion: If the symbol complies to a specific IEC norm. How about 
a comment, that refers to the specific norm?

* what is the intended use of the attribute device=7400 ?

Kai-Martin Knaak
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