Re: gEDA-user: 74xx series

[Magnus Danielson <cfmd@bredband.net>]

From: Dan McMahill <dan@mcmahill.net>
Subject: Re: gEDA-user: 74xx series
Date: Thu, 24 Jun 2004 20:53:16 -0400
Message-ID: <20040625005316.GA3237@bondage.mcmahill.net>

Dan,

> On Fri, Jun 25, 2004 at 02:47:48AM +0200, Paul Surgeon wrote:
> > How does one wire up the power on the 74xx series of chips in gschem?
> > There are no power pins on these logic ICs.
> 
> see http://www.geda.seul.org/docs/20040111/netattrib/index.html
> 
> personally I think implicit connections are EVIL, but that is
> a religous war.

They are not only evil, but they are becoming "A really bad thing" now that we
have chips with core voltage, various different IO-voltages and where important
system properties is decided on this. Also, even for the same voltage each
power-pin may require special care just as much as the signal-carrying pins.

I think it should be phased out as the main principle, but for some designs
you may still consider it usefull.

Cheers,
Magnus