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We all know that the “R” in RISC means “reduced.” Lately, as the number of components that can be manufactured on a chip has increased, CPU designers have been looking at ways to make their processors faster by adding features. We have already talked about many of the features such as on-chip multipliers, very fast floating-point, lots of registers, and on-chip caches. Even with all of these features, there seems to be space left over. Also, because much of the design of the control section of the processor is automated, it might not be so bad to add just a “few” new instructions here and there. Especially if simulations indicate a 10% overall increase in speed!

So, what does it mean when they add 15 instructions to a RISC instruction set architecture (ISA)? Would we call it “not-so-RISC”? A suggested term for this trend is FISC, or fast instruction set computer . The point is that reducing the number of instructions is not the goal. The goal is to build the fastest possible processor within the manufacturing and cost constraints. People will argue forever but, in a sense, reducing the instruction set was never an end in itself, it was a means to an end.

Some of the types of instructions that are being added into architectures include:

  • More addressing modes
  • Meta-instructions such as “decrement counter and branch if non-zero”
  • Specialized graphics instructions such as the Sun VIS set, the HP graphics instructions, the MIPS Digital Media Extentions (MDMX), and the Intel MMX instructions

Interestingly, the reason that the first two are feasible is that adder units take up so little space, it is possible to put one adder into the decode unit and another into the load/store unit. Most visualization instruction sets take up very little chip area. They often provide “ganged” 8-bit computations to allow a 64-bit register to be used to perform eight 8-bit operations in a single instruction.

Questions & Answers

Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
Renato
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
?
Kyle
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
Adin
why?
Adin
what school?
Kyle
biomolecules are e building blocks of every organics and inorganic materials.
Joe
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
research.net
kanaga
sciencedirect big data base
Ernesto
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
Bharti
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
Daniel
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
Maciej
characteristics of micro business
Abigail
for teaching engĺish at school how nano technology help us
Anassong
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
NANO
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
s.
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
Tarell
what is the actual application of fullerenes nowadays?
Damian
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
Tarell
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
Virgil
is Bucky paper clear?
CYNTHIA
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
NANO
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Harper
Do you know which machine is used to that process?
s.
how to fabricate graphene ink ?
SUYASH Reply
for screen printed electrodes ?
SUYASH
What is lattice structure?
s. Reply
of graphene you mean?
Ebrahim
or in general
Ebrahim
in general
s.
Graphene has a hexagonal structure
tahir
On having this app for quite a bit time, Haven't realised there's a chat room in it.
Cied
what is biological synthesis of nanoparticles
Sanket Reply
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, High performance computing. OpenStax CNX. Aug 25, 2010 Download for free at http://cnx.org/content/col11136/1.5
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