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In term of CPU action, data transfer operations are perhaps the simplest type. If both source and destination are registers, then the CPU simply causes data to be transferred from one register to another; this is an operation internal to the CPU. If one or both operands are in memory, then (he CPU must perform some or all of following actions:

1. Calculate the memory address, based on the address mode

2. If the address refers to virtual memory, translate from virtual to actual mem­ory address.

3. Determine whether the addressed item is in cache.

4. If not, issue a command lo the memory module.

Example:

Operation mnemonic Name Number of bits transferred Description
L Load 32 Transfer from memory in register
LH Load half-word 16 Transler from memory to register
ST Store 32 Transfer from register to memory
STH Store half-word 16 Transfer from register to memory

3.2 arithmetic

Most machines provide the basic arithmetic operations of add, subtract, multiply, and divide. These are invariably provided for signed integer (fixed-point) numbers, Often they are also provided for floating-point and packed decimal numbers.

Other possible operations include a variety of single-operand instructions: for example.

• Absolute: Take the absolute value of the operand.

• Negate: Negate the Operand.

• Increment.: Add 1 to the operand.

• Decrement: Subtract 1 from the operand

3.3 logical

Most machines also provide a variety of operations for manipulating individual bits of a word or other addressable units, often referred to as "bit twiddling." They are based upon Boolean operations.

Some of the basic logical operations that can be performed on Boolean or binary data are AND, OR, NOT, XOR, …

These logical operations can be applied bitwise to n-bit logical data units. Thus, if two registers contain the data

(R1) - 10100101 (R2) - 00001111

then

(R1) AND (R2) – 00000101

In addition lo bitwise logical operations, most machines provide a variety of shifting and rotating functions such as shift left, shift right, right rotate, left rotate…

3.4 conversion

Conversion instructions are those that change the format or operate on the format of data. An example is converting from decimal to binary.

3.5 input/output

As we saw, there are a variety of approaches taken, including isolated programmed IO, memory-mapped programmed I/O, DMA, and the use of an I/O processor. Many implementations provide only a few I/O instructions, with the specific actions spec­ified by parameters, codes, or command words.

3.6 system controls

System control instructions are those that can he executed only while the proces­sor is in a certain privileged state or is executing a program in a special privileged area of memory, typically, these instructions are reserved for the use of the oper­ating system.

Some examples of system control operations are as follows. A system control instruction may read or alter a control register. Another example is an instruction to read or modify a storage protection key, such us is used in the S/390 memory system. Another example is access to process control blocks in a multiprogramming system.

Questions & Answers

Do somebody tell me a best nano engineering book for beginners?
s. Reply
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
s.
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
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
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
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
China
Cied
types of nano material
abeetha Reply
I start with an easy one. carbon nanotubes woven into a long filament like a string
Porter
many many of nanotubes
Porter
what is the k.e before it land
Yasmin
what is the function of carbon nanotubes?
Cesar
I'm interested in nanotube
Uday
what is nanomaterials​ and their applications of sensors.
Ramkumar Reply
what is nano technology
Sravani Reply
what is system testing?
AMJAD
preparation of nanomaterial
Victor Reply
Yes, Nanotechnology has a very fast field of applications and their is always something new to do with it...
Himanshu Reply
good afternoon madam
AMJAD
what is system testing
AMJAD
what is the application of nanotechnology?
Stotaw
In this morden time nanotechnology used in many field . 1-Electronics-manufacturad IC ,RAM,MRAM,solar panel etc 2-Helth and Medical-Nanomedicine,Drug Dilivery for cancer treatment etc 3- Atomobile -MEMS, Coating on car etc. and may other field for details you can check at Google
Azam
anybody can imagine what will be happen after 100 years from now in nano tech world
Prasenjit
after 100 year this will be not nanotechnology maybe this technology name will be change . maybe aftet 100 year . we work on electron lable practically about its properties and behaviour by the different instruments
Azam
name doesn't matter , whatever it will be change... I'm taking about effect on circumstances of the microscopic world
Prasenjit
how hard could it be to apply nanotechnology against viral infections such HIV or Ebola?
Damian
silver nanoparticles could handle the job?
Damian
not now but maybe in future only AgNP maybe any other nanomaterials
Azam
Hello
Uday
I'm interested in Nanotube
Uday
this technology will not going on for the long time , so I'm thinking about femtotechnology 10^-15
Prasenjit
can nanotechnology change the direction of the face of the world
Prasenjit Reply
At high concentrations (>0.01 M), the relation between absorptivity coefficient and absorbance is no longer linear. This is due to the electrostatic interactions between the quantum dots in close proximity. If the concentration of the solution is high, another effect that is seen is the scattering of light from the large number of quantum dots. This assumption only works at low concentrations of the analyte. Presence of stray light.
Ali 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, Computer architecture. OpenStax CNX. Jul 29, 2009 Download for free at http://cnx.org/content/col10761/1.1
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