Re: gEDA-user: 74xx symbols

[John Sheahan <jrsheahan@optushome.com.au>]

On Tue, Jul 30, 2002 at 10:18:44PM -0700, Jim Battle wrote:
> 
> Some parts, for example, the 7474 and the 74175, have complementary 
> outputs.  The symbol in the library shows one with a bubble and one 
> without, but the label near the bubble is "/Q".  Although I understand what 
> was meant, it seems like a double negative.  I would label both outputs as 
> "Q" and have a bubble on the negated one.  It is clear in these two cases 
> what is meant, but being consistent is important if "bubble notation" is 
> used more extensively, especially with parts that don't have complementary 
> pins like this.

Be careful here. These are different pins. Doing something that
could connect them together (2 pins with the same name) in netlisting 
tools is a dangerous idea.

Need a compromise between a clean schematic and conveying information
to subsequent steps, be they pcb or simulation or synthesis or just 
eyeballing.

john


> 
> Jim Battle == frustum@pacbell.net