HDL vs. schematics (was Re: ebay - cardamatic)

From: Dwight K. Elvey <dwight.elvey_at_amd.com>
Date: Wed Feb 16 11:49:58 2005

>From: "Eric Smith" <eric_at_brouhaha.com>
>
>I wrote:
>> In VHDL, if you want an adder with inputs A and B, and output C,
>> you would write:
>> A <= B + C;
>
>Well, fubar. It's going to be hard for me to convince anyone of the
>merits of VHDL if I can't write a simple thing like that correctly.
>It obviously should have been:
> C <= A + B;
>
>Sorry about that. What can I say. It's late and I'm tired. G'nite.
>
>Eric
>
>

Hi Eric
 The bug would have been more obvious when the chips got
hot from the output contention on your TTL method ;)
 Still, designing something like the processors we make
would not even be close to possible without some form of
high level circuit language.
 Even so, there are many places where we end up having
redundant paths and inefficient circuits. This is why
a part such as the K7 or K8 continues to evolve. The
design hasn't really changed much but the wasted stuff
gets weeded out over time.
Dwight

Dwight
Received on Wed Feb 16 2005 - 11:49:58 GMT