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Explains how digital systems such as the computer represent numbers. Covers the basics of boolean algebra and binary math.

Computer architecture

To understand digital signal processing systems, we must understand a little about how computers compute. The moderndefinition of a computer is an electronic device that performs calculations on data, presenting theresults to humans or other computers in a variety of (hopefully useful) ways.

Organization of a simple computer

Generic computer hardware organization.

The generic computer contains input devices (keyboard, mouse, A/D (analog-to-digital) converter, etc.), a computational unit , and output devices (monitors, printers, D/A converters). Thecomputational unit is the computer's heart, and usually consists of a central processing unit (CPU), a memory , and an input/output (I/O) interface. What I/O devices might be present on a givencomputer vary greatly.

  • A simple computer operates fundamentally in discrete time. Computers are clocked devices, in which computational steps occur periodically according to ticksof a clock. This description belies clock speed: When you say "I have a 1 GHz computer," you mean that your computertakes 1 nanosecond to perform each step. That is incredibly fast! A "step" does not, unfortunately,necessarily mean a computation like an addition; computers break such computations down into several stages, whichmeans that the clock speed need not express the computational speed. Computational speed is expressed inunits of millions of instructions/second (Mips). Your 1 GHz computer (clock speed) may have a computational speedof 200 Mips.
  • Computers perform integer (discrete-valued) computations. Computer calculations can be numeric (obeying the laws of arithmetic), logical (obeyingthe laws of an algebra), or symbolic (obeying any law you like). An example of a symbolic computation is sorting a list of names. Each computer instruction that performs an elementary numeric calculation --- an addition, a multiplication, or adivision --- does so only for integers. The sum or product of two integers is also an integer, but the quotient oftwo integers is likely to not be an integer. How does a computer deal with numbers that have digits to the rightof the decimal point? This problem is addressed by using the so-called floating-point representation of real numbers. At its heart, however, this representation relies on integer-valued computations.

Representing numbers

Focusing on numbers, all numbers can represented by the positional notation system . Alternative number representation systems exist. For example, we could use stick figure counting orRoman numerals. These were useful in ancient times, but very limiting when it comes to arithmetic calculations: ever triedto divide two Roman numerals? The b -ary positional representation system uses the position of digits ranging from0 to b -1 to denote a number. The quantity b is known as the base of the number system. Mathematically, positional systems represent the positiveinteger n as

d k d k 0 b 1 n k 0 d k b k
and we succinctly express n in base- b as n b d N d N 1 d 0 . The number 25 in base 10 equals 2 10 1 5 10 0 , so that the digits representing this number are d 0 5 , d 1 2 , and all other d k equal zero. This same number in binary (base 2) equals 11001( 1 2 4 1 2 3 0 2 2 0 2 1 1 2 0 )and 19 in hexadecimal (base 16). Fractions between zero and one are represented the same way.
d k d k 0 b 1 f k -1 d k b k
All numbers can be represented by their sign, integer and fractional parts. Complex numbers can be thought of as two real numbers that obey special rules to manipulate them.

Questions & Answers

Three charges q_{1}=+3\mu C, q_{2}=+6\mu C and q_{3}=+8\mu C are located at (2,0)m (0,0)m and (0,3) coordinates respectively. Find the magnitude and direction acted upon q_{2} by the two other charges.Draw the correct graphical illustration of the problem above showing the direction of all forces.
Kate Reply
To solve this problem, we need to first find the net force acting on charge q_{2}. The magnitude of the force exerted by q_{1} on q_{2} is given by F=\frac{kq_{1}q_{2}}{r^{2}} where k is the Coulomb constant, q_{1} and q_{2} are the charges of the particles, and r is the distance between them.
Muhammed
What is the direction and net electric force on q_{1}= 5µC located at (0,4)r due to charges q_{2}=7mu located at (0,0)m and q_{3}=3\mu C located at (4,0)m?
Kate Reply
what is the change in momentum of a body?
Eunice Reply
what is a capacitor?
Raymond Reply
Capacitor is a separation of opposite charges using an insulator of very small dimension between them. Capacitor is used for allowing an AC (alternating current) to pass while a DC (direct current) is blocked.
Gautam
A motor travelling at 72km/m on sighting a stop sign applying the breaks such that under constant deaccelerate in the meters of 50 metres what is the magnitude of the accelerate
Maria Reply
please solve
Sharon
8m/s²
Aishat
What is Thermodynamics
Muordit
velocity can be 72 km/h in question. 72 km/h=20 m/s, v^2=2.a.x , 20^2=2.a.50, a=4 m/s^2.
Mehmet
A boat travels due east at a speed of 40meter per seconds across a river flowing due south at 30meter per seconds. what is the resultant speed of the boat
Saheed Reply
50 m/s due south east
Someone
which has a higher temperature, 1cup of boiling water or 1teapot of boiling water which can transfer more heat 1cup of boiling water or 1 teapot of boiling water explain your . answer
Ramon Reply
I believe temperature being an intensive property does not change for any amount of boiling water whereas heat being an extensive property changes with amount/size of the system.
Someone
Scratch that
Someone
temperature for any amount of water to boil at ntp is 100⁰C (it is a state function and and intensive property) and it depends both will give same amount of heat because the surface available for heat transfer is greater in case of the kettle as well as the heat stored in it but if you talk.....
Someone
about the amount of heat stored in the system then in that case since the mass of water in the kettle is greater so more energy is required to raise the temperature b/c more molecules of water are present in the kettle
Someone
definitely of physics
Haryormhidey Reply
how many start and codon
Esrael Reply
what is field
Felix Reply
physics, biology and chemistry this is my Field
ALIYU
field is a region of space under the influence of some physical properties
Collete
what is ogarnic chemistry
WISDOM Reply
determine the slope giving that 3y+ 2x-14=0
WISDOM
Another formula for Acceleration
Belty Reply
a=v/t. a=f/m a
IHUMA
innocent
Adah
pratica A on solution of hydro chloric acid,B is a solution containing 0.5000 mole ofsodium chlorid per dm³,put A in the burret and titrate 20.00 or 25.00cm³ portion of B using melting orange as the indicator. record the deside of your burret tabulate the burret reading and calculate the average volume of acid used?
Nassze Reply
how do lnternal energy measures
Esrael
Two bodies attract each other electrically. Do they both have to be charged? Answer the same question if the bodies repel one another.
JALLAH Reply
No. According to Isac Newtons law. this two bodies maybe you and the wall beside you. Attracting depends on the mass och each body and distance between them.
Dlovan
Are you really asking if two bodies have to be charged to be influenced by Coulombs Law?
Robert
like charges repel while unlike charges atttact
Raymond
What is specific heat capacity
Destiny Reply
Specific heat capacity is a measure of the amount of energy required to raise the temperature of a substance by one degree Celsius (or Kelvin). It is measured in Joules per kilogram per degree Celsius (J/kg°C).
AI-Robot
specific heat capacity is the amount of energy needed to raise the temperature of a substance by one degree Celsius or kelvin
ROKEEB
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Source:  OpenStax, Fundamentals of electrical engineering i. OpenStax CNX. Aug 06, 2008 Download for free at http://legacy.cnx.org/content/col10040/1.9
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