os intallation

7/30/2019 os intallation

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NYIT

Fall 2012

Homework No: 01

Title: Operating Systems Security

Name: Shivapuram Mithilesh

Class ID#: 19

School ID#: 0837622

Course: Operating Systems Security. . . .

Course ID: CSCI-620-M01

Date: 09/24/2012


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Assignment Contents

1. Identify all peripheral connectors on your hardware system and explain their purpose ...... 01

2. John Von Neumann and Computing ..................................................................................... 28

3. Albert Einstein, the swindler? ............................................................................................... 32

4. References ............................................................................................................................. 35


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1.CPU Related Auditing Activities

1.1 Dump your registers in a text file .Present register dump text file and find your CPU databus width (Hint: read look for data width)

Work:

Data Bus width is 64 Bits

1.2 Read your cpu.txt file and find what instruction set does your CPU support (can execute,can understand)? (Hint: Look for Data Width)

Work:

Instructions sets MMX, SSE, SSE2, SSE3, SSSE3, EM64T are supported.

1.3 What is the purpose of MMX CPU instruction set (Assembly) command CPUID What was the first CPU capable of executing this instruction? Does cpuz.exe utility use the result of this command?

Work:

CPUID is an instruction added to Intel Pentiums (and some later 80486's) that enablesprogrammers to determine what kind of features the current CPU supports, who made it,

various extensions and abilities, and cache information .

Yes, cpuz.exe utility does use the result of this command.1.4 Which Intel Pentium CPU has been upgraded by SSE instruction set, (Was not capable ofunderstanding SSE)?

When was SSE instruction set extension introduced? What is your processors CPUID code?

Work:

SSE is a newer SIMD extension to the Intel Pentium III. SSE wasintroduced in 1999 CPUID Code is 6.F.D and code name is Mermom

CPUZ.txt
http://www.intel.com/http://www.intel.com/


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1.5 What is the name of your CPU? Show the screen shot indicating your CPU name.Work:

Name of my CPU: Intel Mobile Core 2 Duo T5870

Fig 1.5


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1.6 How large were transistors used to manufacture your CPU in nano meters [nm]

Work:

Fig 1.6

1.7 Read cpuz.txt and find the following:a) What is your CPU core internal speed?b) What is the rated external system bus speed?c) How many times is internal CPU (core speed) bus speed larger than external system bus speed?

Work:

a) CPU core internal speed is 798.0MHzb) The rated external system bus speed is 798.0MHzc) Internal CPU (core speed) is equal to the rated external system bus.


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1.8 Does your CPU have L1 cache memory inside? If yes, how large is the internal L1 cachememory of your CPU?

Work:

Yes CPU has L1 cache memory inside.

Fig 1.8

The size of the internal L1 cache memory is 2* 32 kBytes


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1.9 What speed does Windows utility system.exe report?a) Does it report internal CPU speed or external data bus speed?b) Check how many processors does the system have?c) Even Processor device has a driver???

Work:

Control panel:

a.)It is the internal CPU speed


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Fig 1.9.a

a.) There are 2 processors available in my system.


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Fig 1.9.b.1

Test System Processors to make sure the devices are working properly


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Fig 1.9.b.2

Fig 1.9.b.3

Fig 1.9.b.4


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Fig 1.9.b.5

a) Yes the processors have device drivers.

1.10 Go to the site: http://support.microsoft.com/kb/192806Execute all listed control panel tools/utilities from the command prompt and document

each with the screen shots shown in the previous slide.Work:

a) Command : control access.cpl , Utility : Accessibility Options
http://support.microsoft.com/kb/192806http://support.microsoft.com/kb/192806


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Fig 1.10.a

b) Command: Change Directory : cd \

Fig 1.10.b


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c) Command: Control Sysdm.cp

Fig 1.10.c.1

Fig 1.10.c.2d) Command: control access.cpl


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Fig 1.10.d.1

Fig 1.10.d.2


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e) Command: control hdwwiz.cpl

Fig 1.10.e.1

Fig 1.10.e.2


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f) Command: control appwiz.cpl

Fig 1.10.f.1

Fig 1.10.f.2


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g) Command: control timedate.cpl

Fig 1.10.g.1

Fig 1.10.g.2


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h) Command: control desk.cpl

Fig 1.10.h.1

Fig 1.10.h.2


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i) Command: control fonts.cpl

Fig 1.10.i.1

j) Command: control main.cpl keyboard

Fig 1.10.j.1


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Fig 1.10.j.2

k) Command: control main.cpl


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Fig 1.10.k.1

Fig 1.10.k.2

l) Command: control mmsys.cpl

Fig 1.10.l.1


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Fig 1.10.l.2

m)Command: control printers

Fig 1.10.m.1


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Fig 1.10.m.2

n)

Command: control inetcpl.cpl

Fig 1.10.n.1


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Fig 1.10.n.2

o) Command: control joy.cpl


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Fig 1.10.o.1

Fig 1.10.o.2

p) Command: control modem.cpl


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Fig 1.10.p.1

Fig 1.10.p.2

q) Command: control sticpl.cpl


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Fig 1.10.q.1

Fig 1.10.q.2

r) Command: control intl.cpl


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Fig 1.10.r.1

2.John Von Neumann and ComputingIntroduction:

We can all think clearly, more or less, some of the time, but von Neumann's clarity ofthought was orders of magnitude greater than that of most of us, all the time. For von Neumann it

seemed to be impossible to be unclear in thought or in expression said Paul Halmos. Keeping

up with him was all but impossible. The feeling was you were on a tricycle chasing a racing carsaid Israel Halperin.

John von Neumann (December 28, 1903 February 8, 1957) was a Hungarian Americanmathematician. Von Neumann was the oldest of 3 children of a banker, and his speed of learning

new ideas and of solving problems stood out early. At 6, he could divide two 8-digit numbers in

his head; by 8 he had mastered calculus; by 12 he was at the graduate level in mathematics. Hecould memorize pages on sight. At 17, his father tried to convince him to become something

more financially practical than a mathematician, and von Neumann agreed to study chemistry as

well. He arranged to study chemistry in Berlin and then Zurich and mathematics in Budapest. In

1926, at 23, he received a degree in chemical engineering in Zurich and a Ph.D. in mathematicsin Budapest. From the start, mathematics provided well enough for him, and he never had to

resort to the chemistry.

John von Neumann was unquestionably one of the most brilliant scientists of the twentiethcentury. He made major contributions to quantum mechanics and mathematical physics and in

1943 began a new and all-too-short career in computer science.He is generally regarded as one of

the greatest mathematicians in modern history.


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The mathematician Jean Dieudonn called von Neumann "the last of the great

mathematicians",while Peter Lax described him as possessing the most "fearsome technicalprowess" and "scintillating intellect" of the century.Even in Budapest, in the time that produced

geniuses like Theodore von Krmn, Le Szilrd, Eugene Wigner, and Edward Teller, his

brilliance stood out.

Von Neumann was a pioneer of the application of operator theory to quantum mechanics,

in the development of functional analysis, a principal member of the Manhattan Project and theInstitute for Advanced Study in Princeton (as one of the few originally appointed), and a key

figure in the development of game theory and the concepts of cellular automata and the universal

constructor. Along with Teller and Stanisaw Ulam, von Neumann worked out key steps in the

nuclear physics involved in thermonuclear reactions and the hydrogen bomb.

For the next 3 years, von Neumann worked mainly in the new field of operator theory inmathematics and on applying it to the new field of quantum theory in physics. His first book,

published in 1932, was on quantum mechanics. In 1930, von Neumann visited Princeton for a

year and then became a professor there.In 1933, the Institute for Advanced Study was formed,

and he became one of the 6 full-time people in the School of Mathematics.

World War II drastically changed von Neumann's areas of interest. Until 1940 he had

been a great pure mathematician and had made a number of important theoretical contributions

in physics. During and after the war, he became one of the best applied mathematicians. He also

had a superb grasp of practicalities, and, when some of the best engineers in the world were atLos Alamos trying to decide how to bring the atomic fuel together quickly enough to create an

explosion the (A bomb), this mathematician came up with the workable answer -- implosion. He

even had time to found the area of game theory, "one of the major scientific contributions of the

first half of the 20th century."

Neumann and Computers:

Apart from all the above he is the father of computing theory and practice.Any discussion

of computer architectures, of how computers and computer systems are organized, designed, and

implemented, inevitably makes reference to the "von Neumann architecture" as a basis for

comparison. And of course this is so, since virtually every electronic computer ever built has

been rooted in this architecture. The name applied to it comes from John von Neumann,w as the

first to spell out the requirements for a general purpose electronic computer.

From the beginning von Neumann took a wider and more theoretical view than other

computer pioneers. In the now famous EDVAC report of 1945, von Neumann clearly stated the

idea of a stored program that resides in the computer's memory along with the data it was to

operate on. This stored program computer was described in terms of idealized neurons,

highlighting the analogy between the digital computer and the human brain. Aspray describes

von Neumann's development during the next decade, and almost entirely alone, of a theory of

complicated information processing systems, or automata, and the introduction of themes such as


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learning, reliability of systems with unreliable components, self-replication, and the importance

of memory and storage capacity in biological nervous systems; many of these themes remain at

the heart of current investigations in parallel or neurocomputing.

During the last part of the war he became involved with the development of computing

machines and made several fundamental contributions.It was his idea to store the program (thesequence of instructions) in the machine as simply another kind of electronic data. Until then, in

order to reprogram a computer a person had to physically rewire it. Computers which perform

their operations sequentially are called "von Neumann machines" as opposed to recent types

which can perform several operations at once using "parallel processing." He, together with Stan

Ulam, developed the Monte Carlo technique, a commonly used means of simulating complex

situations in science and business.

After the war, von Neumann continued his work with computers, and was generally very

active in government service.When Von Neumann finished building his computer he had to find

a use for it. In his eyes the only useful thing to do was mathematics so he and fellowmathematicans Fermi and Ulam invented a simulation method that they called the Monte Carlo

method. This method simulates random events using the computer.

In Buffon's needle problem the JAVA applet uses Von Neumann's simulation method to

validate the correct value of pi. Von Neumann's pervading contribution was promoting

computers for military and scientific research. As the United States entered World War II,

computers were primitive. Typically used to calculate mathematical tables, they required

operators manually to plug in connector cables for each task. Von Neumann's group put the

commands controlling the computer's action sequence into its electronic memory, making it fast

and flexible. In 1951, a computer simulated the triggering of the first thermonuclear explosion.Von Neumann pioneered the abstract study of computation, with his British student Alan Turing,

and founded game theory,used to analyze deterrence and escalation.

EDSAC, in full Electronic Delay Storage Automatic Calculator, the first full-size stored-

program computer, built at the University of Cambridge, Eng., by Maurice Wilkes and others to

provide a formal computing service for users. EDSAC was built according to the von Neumann

machine principles became operational in 1949. Wilkes built the machine chiefly to study

computer programming issues, which he realized would become as important as the hardware

details.

Von Neumann devoted most of his "Preliminary Discussion" to the design of the

arithmetic unit.The details of this are the least interesting part of the paper from the standpoint of

the organization of his computer, and its influence on future developments. The capabilities of

the arithmetic unit were limited to the performance of some arbitrary subset of the possible

arithmetic operations. He observes that "the inner economy of the arithmetic unit is determined


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by a compromise between the desire for speed of operation...and the desire for simplicity, or

cheapness, of the machine" [Burks, et al., p. 36].

What is interesting, and important, is that this issue continued to dominate design

decisions for many years. It is less true now that hardware costs have become a substantially less

critical concern.The concepts put forth by von Neumann were, for their time, quite remarkable--so much so that they provided the foundations for all of the early computers developed, and for

the most part are still with us today. Why then do we require something different? What is it

about this architecture that we find constraining and counterproductive? Why must there be new,

different, "non-von Neumann" machines?

The final phase of Von Neumann's work was represented by the Silliman lectures which

he was to have given at Yale in 1956 and which were embodied in his posthumous The

Computer and the Brain (1958). His terminal illness made the lectures impossible but the book

made clear the form they would have taken. The work was that of the mathematician operating in

the field of brain studies and emphasized the differences and similarities between brains andcomputers. The nerve impulse is primarily electrical, apparently digital, and has time

characteristics not unlike the pulses in a computer. Overall, computer speeds then were slower at

performing the range of functions performed by the braina state of affairs that has gradually

changed. The languages of the brain involve mathematical, logical, and statistical methods, and

Von Neumann foresaw that in describing the brain and the nervous system new forms of

mathematics would be developed. This has occurred in the forms of uncertainty logics and

empirical logics. The precision of brain operation he thought of as logical, its computational

working as arithmetic, and the functional description as statistical.

HONORS:

The John von Neumann Theory Prize of the Institute for Operations Research and the

Management Sciences (INFORMS, previously TIMS-ORSA) is awarded annually to an

individual (or group) who have made fundamental and sustained contributions to theory in

operations research and the management sciences.

The IEEE John von Neumann Medal is awarded annually by the IEEE "for outstanding

achievements in computer-related science and technology."The John von Neumann Lecture is

given annually at the Society for Industrial and Applied Mathematics (SIAM) by a researcher

who has contributed to applied mathematics, and the chosen lecturer is also awarded a monetaryprize. The crater Von Neumann on the Moon is named after him. The John von Neumann

Computing Center in Princeton, New Jersey was named in his honour.The professional society

of Hungarian computer scientists, John von Neumann Computer Society, is named after John

von Neumann.On February 15, 1956, Neumann was presented with the Presidential Medal of

Freedom by President Dwight Eisenhower.


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On May 4, 2005 the United States Postal Service issued the American Scientists commemorative

postage stamp series, a set of four 37-cent self-adhesive stamps in several configurations. The

scientists depicted were John von Neumann, Barbara McClintock, Josiah Willard Gibbs, and

Richard Feynman.The John von Neumann Award of The Rajk Lszl College for Advanced

Studies was named in his honour, and has been given every year since 1995 to professorswho

have made an outstanding contribution to the exact social sciences and through their work have

strongly influenced the professional development and thinking of the members of the college.He

received numerous awards, was president of the American Mathematical Society and was a

member of the Atomic Energy Commission.Any one of several of his contributions would have

been enough to earn him a firm place in history.

This brief summary can never do full justice to the achievements of this great human mind .What

amazes is that human brain capabilities are far superior to any computer that he created. Neuman

stands as a true example for this and inspires the reader to look beyond the lines and challenge

our minds. Von Neumann will be remembered as one of the greatest minds of this century.Von

Neumann really was a legend in his own time

3.Albert Einstein, the swindler?

Albert Einstein is today revered as the Father of Modern Science. His wrinkled

face and wild hair has become a symbol for scientific genius and his famous E = mc^2

equation is repeatedly used as the symbol for something scientific and intellectual. And yet there

has for years been mounting evidence that this Father of Modern Science was nothing but a

con man, lying about his ideas and achievements, and stealing the work and the research of

others. The most glaring evidence against Einstein concerns his most famous equation. One

websitenotes The equation E=mc^2, which has been forever linked to Einstein & his Theory of

Relativity was not originally published by Einstein. According to Umberto Bartocci, a professor

at the University of Perugia and a historian of mathematics, this famous equation was first

published by Olinto De Pretto two years prior to Einsteins publishing of the equation. In 1903

De Pretto published his equation in the scientific magazine Atte and in 1904 it was republished

by the Royal Science Institute of Veneto. Einsteins research was not published until 1905Einstein was well versed in Italian and even lived in Northern Italy for a brief time.

It is unheard of to pass over the original inventor of an equation and to give credit

to someone, who claims to have derived it AFTER the equation and its derivation have been

published. The equation E=mc^2 should be called the De Pretto Equation not the Einstein

Equation. This raises the question: What sort of man was Einstein? Is there evidence that he

may have been prone to unethical behavior? One website reports Einstein was still far from
http://www.italiansrus.com/articles/emc2.htmhttp://www.italiansrus.com/articles/emc2.htmhttp://www.italiansrus.com/articles/emc2.htmhttp://www.italiansrus.com/articles/emc2.htm


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the ideal husband. A year before they married, Maric gave birth to a daughter, Lieserl, while

Einstein was away. The childs fate is unknown she is presumed to have been given up for

adoption, perhaps under pressure from Einstein, who is thought to have never seen his first born.

After the marriage, Mileva bore two sons but the family was not to stay together. Einstein began

an affair with his cousin Elsa Lowenthal while on a trip to Berlin in 1912, leaving Mileva and hisfamily two years later. Einstein and Mileva finally divorced in 1919, but not until after Einstein

sent his wife a list of conditions under which he was willing to remain married. The list

included such autocratic demands as You are neither to expect intimacy nor to reproach me in

any way. After the divorce, he saw little of his sons. The elder, Hans Albert, later reflected

Probably the only project he ever gave up on was me. The younger, Eduard, was diagnosed

with schizophrenia and died in an asylum. Einstein married Elsa soon after the divorce, but a few

years later began an affair with Betty Neumann, the niece of a friend Accusations of

plagiarism arent limited to Mileva its also been claimed that Einstein stole the work of a host

of other physicists. One question which may remain moot is quite how much Einstein drew from

the work of Hendrik Lorentz and Henri Poincare in formulating the theory of special relativity.

Elements of Einsteins 1905 paper paralleled parts of a 1904 paper by Lorentz and a

contemporary paper by Poincare. Although Einstein read earlier papers by the two, he claimed

not to have seen these later works before writing the 1905 paper. One apparently damning fact is

that the 1905 paper on special relativity had no references, suggesting that Einstein was

consciously hiding his tracks.

One source notes David Hilbert submitted an article containing the correct field

equations for general relativity five days before Einstein. Another source notes Einstein

presented his paper on November 25, 1915 in Berlin and Hilbert had presented his paper on

November 20 in Gttingen. On November 18, Hilbert received a letter from Einstein thanking

him for sending him a draft of the treatise Hilbert was to deliver on the 20th. So, in fact, Hilbert

had sent a copy of his work at least two weeks in advance to Einstein before either of the two

men delivered their lectures, but Einstein did not send Hilbert an advance copy of his.

Apparently Hilberts work was soon to become Einsteins work.

The historic record is readily available and the truth is known to many scientists and

historians, even if they are afraid to say anything. The idea that light had a finite speed was

proven by Michelson and Morley decades before Einstein. Hendrik Lorentz determined the

equations showing relativistic time and length contractions which become significant as the

speed of light is approached. These gentlemen along with David Hilbert and Olinto De Pretto

have been airbrushed out of the picture so that Einstein could be given the credit for what they

had done.


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Einstein appeared to latch onto his first wife, a much more talented student three years his

senior, to compensate for his own limited abilities. Another website notes: in 1927, H.

Thirring wrote, H. Poincare had already completely solved the problem of time several years

before the appearance of Einsteins first work (1905). . . . Sir Edmund Whittaker in his detailed

survey, A History of the Theories of Aether and Electricity, Volume II, (1953), included achapter entitled The Relativity Theory of Poincare and Lorentz. Whittaker thoroughly

documented the development of the theory, documenting the authentic history, and demonstrated

through reference to primary sources that Einstein held no priority for the vast majority of the

theory. Einstein offered no counter-argument to Whittakers famous book. . .

Einstein was a minor contributor at best and in any case an intellectual thief and pretentious

braggart. Einstein was still alive when Whitakers book was published and he said NOTHING

about it. No libel suit, no refutation, no public comment at all.

Einstein was the first great fraudster and idea-thief in modern science. His theft of Olinto

De Prettos equation E = mc^2 gave him considerable scientific credibility which he built a

career on. De Pretto was not a career physicist and spent his life as an industrialist, passing away

in 1921. De Pretto had published his equation twice before Einstein and was no doubt amazed

that someone could claim credit for his work. Einstein used and eventually discarded his first

wife, Mileva, who was a much more brilliant student than Einstein and is suspected of writing

much of Einsteins early work. (She may have been reluctant to expose Einstein since he was

still the father of her children.) David Hilberts work on the equations for Special Relativity was

submitted for publication before Einstein and was sent to Einstein as correspondence. Einstein

claimed credit for the equations which Hilbert derived. (David Hilbert passed away in 1943.)

Some university professors have stolen work from their graduate students and it would be

interesting to see if any of Einsteins students complained of such thievery. A plagiarist seldom

stops plagiarizing especially when he keeps getting away with it. Complaints against Einstein

however seem to disappear down the Orwellian memory hole. Einstein is clearly a sacred cow to

many. A few have even used the word heresy to describe serious well -documented criticism

and charges of plagiarism against Einstein. The truth eventually wins out and Einstein will

someday be best known as a great fraud instead of a great physicist.


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4. Status register

Work:

A status register or flag register (also: condition code register,program status word, PSW, etc.)is a collection offlag bits for a processor. An example is the FLAGS register of the x86

architecture.

The status register is a hardware register which contains information about the state of

the processor. Individual bits are implicitly or explicitly read and/or written by the machine

code instructions executing on the processor. The status register in a traditional processor design

includes at least three central flags: Zero, Carry, and Overflow, which are set or cleared

automatically as side effects of arithmetic operations. They may then be tested via conditional

branch or jump instructions. A status register may often have other fields as well, such as more

specialized flags, interruptenable bits, and similar types of information. During an interrupt, the

status of the thread currently executing can be preserved (and later recalled) by storing the

current value of the status register along with the program counter and other active registers into

the machine stackor a reserved area of memory.

^ S: Status flag C: Control flag X: System flag

Where some bits are discussed below:

Bit 0CF: In computer processors the carry flag (usually indicated as the C flag) is a single bit

in a system status (flag) register used to indicate when an arithmetic carry or borrow has beengenerated out of the most significant ALU bit position. When used after an arithmetic operation

it could be considered to be the unsigned equivalent of the overflow flag. In some machines such

as the MOS Technology 6502, after a subtract operation the carry flag indicates the absence of a

borrow.

Bit 2In computer processors the parity flag indicates if the number of set bits is odd or even in

the binary representation of the result of the last operation. It is normally a single bit in a

processor status register.For example, assume a machine where a set parity flag indicates even

parity. If the result of the last operation were 26 (11010 in binary), the parity flag would be 0

since the number of set bits is odd. Similarly, if the result were 102 (1100110 in binary) then theparity flag would be 1.

Bit 4The Adjust flag (also known as the Auxiliary flag) is a flag stored in the FLAGS register

on all x86 compatible CPUs. It is bit 4. It is used to indicate when an arithmetic carry or borrow

has been generated out of the 4 least significant bits. It is primarily used in BCD arithmetics.
http://en.wikipedia.org/wiki/Status_registerhttp://en.wikipedia.org/wiki/Flag_(computing)http://en.wikipedia.org/wiki/Bithttp://en.wikipedia.org/wiki/Central_processing_unithttp://en.wikipedia.org/wiki/FLAGS_register_(computing)http://en.wikipedia.org/wiki/X86_architecturehttp://en.wikipedia.org/wiki/X86_architecturehttp://en.wikipedia.org/wiki/Hardware_registerhttp://en.wikipedia.org/wiki/Central_processing_unithttp://en.wikipedia.org/wiki/Machine_codehttp://en.wikipedia.org/wiki/Machine_codehttp://www.surfcanyon.com/search?f=slc&q=status%20register&p=wtigckhttp://en.wikipedia.org/wiki/Interrupthttp://en.wikipedia.org/wiki/Program_counterhttp://en.wikipedia.org/wiki/Call_stackhttp://en.wikipedia.org/wiki/Call_stackhttp://en.wikipedia.org/wiki/Program_counterhttp://en.wikipedia.org/wiki/Interrupthttp://www.surfcanyon.com/search?f=slc&q=status%20register&p=wtigckhttp://en.wikipedia.org/wiki/Machine_codehttp://en.wikipedia.org/wiki/Machine_codehttp://en.wikipedia.org/wiki/Central_processing_unithttp://en.wikipedia.org/wiki/Hardware_registerhttp://en.wikipedia.org/wiki/X86_architecturehttp://en.wikipedia.org/wiki/X86_architecturehttp://en.wikipedia.org/wiki/FLAGS_register_(computing)http://en.wikipedia.org/wiki/Central_processing_unithttp://en.wikipedia.org/wiki/Bithttp://en.wikipedia.org/wiki/Flag_(computing)http://en.wikipedia.org/wiki/Status_register


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Bit 6The Zero Flag is a flag stored in the FLAGS register on all x86 compatible CPUs. It is bit

6. When it is set to 1, it means that the result of an instruction was zero. The Zero Flag is

changed by all math instructions and the CMP instruction (a compare instruction works by

subtracting the two values).

Bit 7In computer processor the negative flag or sign flag is a single bit in a system status (flag)register used to indicate whether the result of last mathematic operation resulted in a value whose

most significant bit was set. In a two's complement interpretation of the result, the negative flag

is set if the result was negative.

Bit 8The Trap Flag is a flag defined in the x86 processor's flags register.The trap flag's state is

used when using the x86's debugging features. When set, the x86 processor will execute only one

instruction at a time and then call interrupt 1 (the debug interrupt) to allow an attached debugger

to inspect the program as it executes.The trap flag can also be set by the x86's debug registers.

Bit 9 IF (Interrupt Flag) is a system flag bit in the x86 architecture's FLAGS register, whichdetermines whether or not the CPU will handle maskable hardware interrupts.The bit, which is

bit 9 of the FLAGS register, may be set or cleared by programs with sufficient privileges, as

usually determined by the Operating System.

If the flag is set to 1, maskable hardware interrupts will be handled. If cleared (set to 0), such

interrupts will be ignored. IF does not affect the handling of non-maskable interrupts or software

interrupts generated by the INT instruction.

Bit 10DF: When it is set to 0, it means that instructions, that autoincrement the source index

and destination index (like movs) will increase both of them. In case it is set to 1, the instruction

will decrease them. This flag is used to determine the direction (forward or backward) in which

several bytes of data will be copied from one place in the memory, to another. The direction is

important mainly when the original data position in memory and the target data position overlap.

Bit 11OF: It is used to indicate when an arithmetic overflow has occurred in an operation.Theoverflow flag is set when the Most Significant Bit (MSB) is set or cleared.

Bit 12, 13 IOPL: In protected and long mode, it shows the I/O privilege level of the current

program or task. The CPL (Current Privilege Level) of the task or program must be less than or

equal to the IOPL in order for the task or program to access I/O ports

Bit 17In the 80386 microprocessor and later, virtual 8086 mode (also called virtual real mode,V86-mode or VM86) allows the execution of real mode applications that are incapable of

running directly in protected mode while the processor is running a protected mode operatingsystem.

Program Status Word: The program status word (PSW) is an area of memory or a hardware

register which contains information about program state used by the operating systemand the


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underlying hardware. It will normally include a pointer (address) to the next instruction to be

executed. The program status word typically contains an error status field and condition codes

such as the interrupt enable/disable bit and a supervisor / user mode bit. In general, the PSW is

used to control instruction sequencing and to hold and indicate the status of the system in relation

to the program currently being executed. The active or controlling PSW is called the current

PSW. By storing the current PSW during an interruption, the status of the CPU can be preserved

for subsequent inspection. By loading a new PSW or part of a PSW, the state of the CPU can be

initialized or changed.


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5.References1. www.msdn2.microsoft.com2. http://support.microsoft.com/kb/2883023. http://en.wikipedia.org/wiki/FLAGS_register_(computing)4. http://us.altermedia.info/news-of-interest-to-white-people/albert-einstein-plagiarist-and-

%20fraud_1295.html

5. http://en.wikipedia.org/wiki/Carry_flag6. http://en.wikipedia.org/wiki/Parity_flag7. http://en.wikipedia.org/wiki/Adjust_flag8. http://en.wikipedia.org/wiki/Zero_flag9. http://en.wikipedia.org/wiki/Sign_flag10.http://en.wikipedia.org/wiki/Trap_flag11.http://en.wikipedia.org/wiki/IF_(x86_flag)12.http://en.wikipedia.org/wiki/Direction_flag13.http://en.wikipedia.org/wiki/Overflow_flag14.http://en.wikipedia.org/wiki/IOPL15.http://en.wikipedia.org/wiki/Virtual_8086_mode16.http://publib.boulder.ibm.com/infocenter/zvm/v5r3/index.jsp?topic=/com.ibm.zvm.v53.h

cpb6/hcsa4b1042.htm17.http://www.keil.com/support/man/docs/is51/is51_ov_cpupsw.htm18.http://www.maddes.net/m6809pm/sections.htm19.http://softpixel.com/~cwright/programming/simd/cpuid.php20.http://www.techterms.com/definition/isa21.http://www.kids-online.net/learn/click/details/isa2.html22.http://www.computer-hardware-explained.com/pci-slots.htmlhttp://en.wikipedia.org/wiki/Universal_Serial_Bus

23.http://en.wikipedia.org/wiki/Serial_port24.http://www.spectronicsinoz.com/article/computer-connectors-guide25.http://en.wikipedia.org/wiki/John_von_Neumann26.http://www.computinghistorymuseum.org/bookinfo/bio1.pdf27.http://mitpress.mit.edu/catalog/item/default.asp?ttype=2&tid=4961


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28.http://support.microsoft.com/kb/19280629.http://en.wikipedia.org/wiki/JACK_Audio_Connection_Kit30.http://en.wikipedia.org/wiki/Socket_7

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