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Universal logic modules vs NAND-like modules

Started by Candida Ferreira May 15, 2005
Hi everyone,

Is there a proper name to distinguish NAND-like universal modules from
ordinary ones, that is, the ones formed by a function F, plus NOT, plus ONE,
and ZERO?

Thanks,
Candida
---
Candida Ferreira, Ph.D.
Chief Scientist, Gepsoft
http://www.gene-expression-programming.com/author.asp

GEP: Mathematical Modeling by an Artificial Intelligence
http://www.gene-expression-programming.com/gep/Books/index.asp
Modeling Software
http://www.gepsoft.com/gepsoft/
                          Get APS 3.0 Std free with the book!



Question doesn't make sense to me.

Try again or pick up a logic book.

Maybe you refer to fixed logic v tablelogic?

So what brings someone in your esteemed field down into the hw
trenches.

johnjakson at usa dot com

NAND and NOR functions by themselves can be used to describe any other
function, including NOT, ZERO and ONE. But, for instance, the 3-multiplexer,
which is also by definition an ULM, can not by itself describe a NAND gate
as it is unable to create a NOT gate. But there are other functions that
behave exactly like NAND or NOR gates in the sense that, by themselves, they
can also describe any other function. Do such functions have a name? I think
there is something special about them and I would like to distinguish them
from the ordinary ULMs.

Candida
---
Candida Ferreira, Ph.D.
Chief Scientist, Gepsoft
http://www.gene-expression-programming.com/author.asp

GEP: Mathematical Modeling by an Artificial Intelligence
http://www.gene-expression-programming.com/gep/Books/index.asp
Modeling Software
http://www.gepsoft.com/gepsoft/
                          Get APS 3.0 Std free with the book!


"JJ" <johnjakson@yahoo.com> wrote in message
news:1116236810.947060.102680@o13g2000cwo.googlegroups.com...
> Question doesn't make sense to me. > > Try again or pick up a logic book. > > Maybe you refer to fixed logic v tablelogic? > > So what brings someone in your esteemed field down into the hw > trenches. > > johnjakson at usa dot com >
Candida Ferreira wrote:
> NAND and NOR functions by themselves can be used to describe any
other
> function, including NOT, ZERO and ONE. But, for instance, the
3-multiplexer,
> which is also by definition an ULM, can not by itself describe a NAND
gate
> as it is unable to create a NOT gate. But there are other functions
that
> behave exactly like NAND or NOR gates in the sense that, by
themselves, they
> can also describe any other function. Do such functions have a name?
I think
> there is something special about them and I would like to distinguish
them
> from the ordinary ULMs.
I don't follow. Multiplexers are as complete as any logic element. I'm not sure what you mean by a 3-multiplexer, but I will assume you mean a 2 input mux with a single control input. You can get a NOT function by putting a 1 on the I0 input and a 0 on the I1 input and your signal on the sel input.
Candida Ferreira wrote:

> NAND and NOR functions by themselves can be used to describe any other > function, including NOT, ZERO and ONE.
True. NCR once produced a computer using only NAND gates.
> But, for instance, the 3-multiplexer, > which is also by definition an ULM, can not by itself describe a NAND gate > as it is unable to create a NOT gate.
A four to one mux can make any boolean function of two variables. The mux selector takes the two inputs and the mux inputs become a function code.
> But there are other functions that > behave exactly like NAND or NOR gates in the sense that, by themselves, they > can also describe any other function.
A NAND or NOR is the simplest case, but requires multiple instances. A 4:1 mux is the simplest complete case for two inputs. There are cases in between and redundant cases, but those are not very interesting.
> Do such functions have a name? I think > there is something special about them and I would like to distinguish them > from the ordinary ULMs.
Not in digital electronics. Do some research on "Lattice Theory" -- Mike Treseler
"rickman" wrote:

> I don't follow. Multiplexers are as complete as any logic element. > I'm not sure what you mean by a 3-multiplexer, but I will assume you > mean a 2 input mux with a single control input. You can get a NOT > function by putting a 1 on the I0 input and a 0 on the I1 input and > your signal on the sel input.
That's true and does not contradict the definition of a ULM, but you need the 1 and the 0 to create a NOT. Without them you cannot create a NOT with the 3-multiplexer. But there are other functions, such as the NAND and the NOR functions that, by themselves, can create any other function, without needing the NOT, the ZERO and the ONE. These are the ULMs I want to distinguish from the more ordinary ones. Candida --- Candida Ferreira, Ph.D. Chief Scientist, Gepsoft http://www.gene-expression-programming.com/author.asp GEP: Mathematical Modeling by an Artificial Intelligence http://www.gene-expression-programming.com/gep/Books/index.asp Modeling Software http://www.gepsoft.com/gepsoft/ Get APS 3.0 Std free with the book!
On Mon, 16 May 2005 14:42:37 GMT, "Candida Ferreira"
<cferreira@seehomepage.com> wrote:

>"rickman" wrote: > >> I don't follow. Multiplexers are as complete as any logic element. >> I'm not sure what you mean by a 3-multiplexer, but I will assume you >> mean a 2 input mux with a single control input. You can get a NOT >> function by putting a 1 on the I0 input and a 0 on the I1 input and >> your signal on the sel input. > >That's true and does not contradict the definition of a ULM, but you need >the 1 and the 0 to create a NOT. Without them you cannot create a NOT with >the 3-multiplexer. But there are other functions, such as the NAND and the >NOR functions that, by themselves, can create any other function, without >needing the NOT, the ZERO and the ONE. These are the ULMs I want to >distinguish from the more ordinary ones.
I've seen them named "complete logic gate set" or "primitive logic gate set". I am not sure whether there is a universally accepted name.
"Candida Ferreira" <cferreira@seehomepage.com> writes:

> "rickman" wrote: > > > I don't follow. Multiplexers are as complete as any logic element. > > I'm not sure what you mean by a 3-multiplexer, but I will assume you > > mean a 2 input mux with a single control input. You can get a NOT > > function by putting a 1 on the I0 input and a 0 on the I1 input and > > your signal on the sel input. > > That's true and does not contradict the definition of a ULM, but you need > the 1 and the 0 to create a NOT. Without them you cannot create a NOT with > the 3-multiplexer. But there are other functions, such as the NAND and the > NOR functions that, by themselves, can create any other function, without > needing the NOT, the ZERO and the ONE. These are the ULMs I want to > distinguish from the more ordinary ones.
Do you mean, they are _generators_ for whole family of binary functions ? MB PS: there's a booklet by Emil Post on this subject of binary functions. Forgot the title, sorry. -- Michel BILLAUD billaud@labri.fr LABRI-Universit&#4294967295; Bordeaux I tel 05 4000 6922 / 05 5684 5792 351, cours de la Lib&#4294967295;ration http://www.labri.fr/~billaud 33405 Talence (FRANCE)
> Do you mean, they are _generators_ for whole family of binary functions ?
Yes, exactly like NAND and NOR. Just to give another example, you can also do that with the function a'c'+b'c. Candida --- Candida Ferreira, Ph.D. Chief Scientist, Gepsoft http://www.gene-expression-programming.com/author.asp GEP: Mathematical Modeling by an Artificial Intelligence http://www.gene-expression-programming.com/gep/Books/index.asp Modeling Software http://www.gepsoft.com/gepsoft/ Get APS 3.0 Std free with the book! Michel Billaud wrote:
> "Candida Ferreira" <cferreira@seehomepage.com> writes: > > > "rickman" wrote: > > > > > I don't follow. Multiplexers are as complete as any logic element. > > > I'm not sure what you mean by a 3-multiplexer, but I will assume you > > > mean a 2 input mux with a single control input. You can get a NOT > > > function by putting a 1 on the I0 input and a 0 on the I1 input and > > > your signal on the sel input. > > > > That's true and does not contradict the definition of a ULM, but you
need
> > the 1 and the 0 to create a NOT. Without them you cannot create a NOT
with
> > the 3-multiplexer. But there are other functions, such as the NAND and
the
> > NOR functions that, by themselves, can create any other function,
without
> > needing the NOT, the ZERO and the ONE. These are the ULMs I want to > > distinguish from the more ordinary ones. > > Do you mean, they are _generators_ for whole family of binary functions ? > > MB > > PS: there's a booklet by Emil Post on this subject of binary > functions. Forgot the title, sorry. > > -- > Michel BILLAUD billaud@labri.fr > LABRI-Universit&#4294967295; Bordeaux I tel 05 4000 6922 / 05 5684 5792 > 351, cours de la Lib&#4294967295;ration http://www.labri.fr/~billaud > 33405 Talence (FRANCE)
Mike Treseler wrote:
> Candida Ferreira wrote: > > > NAND and NOR functions by themselves can be used to describe any
other
> > function, including NOT, ZERO and ONE. > > True. NCR once produced a computer using only NAND gates. >
It's a good bet that they didn't use any NAND gates to generate ones or zeroes! This sounds like a mathematician kind of question rather than engineering...