# Coded Data Stored in a Computer

Topics: Binary numeral system, File format, Audio file format Pages: 20 (4179 words) Published: February 25, 2015
UNIT19
ASSIGNMENT 1

The Devil is in the
Data
Robert Mullins 20179396
1

CODED DATA STORED WITHIN A
COMPUTER

Computer do not understand the alphabet system. When typing letters or numbers into the computer, the computer system instantly translates those inputs into binary so the computer can understand.

The keyboard system is codded and then read by the computer using a dictionary called the ASCII table. This allows the computer to understand what the user inputs and then visual displays the correct data on the screen. An example of this is “A is equal to 65 which would be translated into “1000001” binary or “0110 0101” which is called Binary Coded Decimal (BCD) this is when the computer breaks down each part into a single unit and works it out with binary code “A = 65 F”. Standard ASCII character sets use only 7 bits for each character inputted. Some character sets use 8 bits which in turn gives them a additional 128 characters.

The extra characters that are available are used to represent non-English characters, graphic symbols and also mathematical symbols. Some companies have proposed character extensions for these 128 characters. The operating system DOS uses high ASCII. A more universal standard is the ISO Latin 1 set which is also used by most operating system and web browsers. Every computer is coded using Unicode. The reason being is because there is not enough characters in the ASCII. Nowadays with Unicode you can use any language. Unicode consists of 1,114,112 characters, this covers all languages, emoticons and symbols.

2

PURE BINARY & BINARY
CODED DECIMAL
A pure binary integer is a whole number. It can be any number of binary digits an example of this is as followed. 0000 0010 is 2 0000 0011, 3 each place to the left is double the amount of the previous place from the right. In decimal or base 10 each number is 10x the previous position to the right. So 10b 10 is 10, 110 b10 is 100 or 10x larger than the previous number. In binary, you have the use of two digits: ones and zeroes. A one has the value 1 and a zero has the value 0. The place value of digits in a number therefore increases by powers of two. In decimal, you have units, tens, hundreds, thousands and so on. In binary, this is different. The first digit is "ones" or "units". The second digit (moving leftwards) is "twos", the third is "fours", the fourth is "eights" and so on. (Or, in other words, 2^0, 2^1, 2^2, 2^3, etc.) As an example of the number 42 in binary is below:

101010 = one 32 no 16s one 8 no 4s one 2 no 1s
However, in binary coded decimal, you take each decimal digit of the number and represent it separately in binary. So, taking 42 as the example again, you might represent it like this: 0100 0010
3

DATABUS &
BUS
Bus is a computer bus (which
is a series of lines
that connects two or more devices) that is used in order to

or write to a memory location it will specify that memory
location on the address bus. The width of the address bus will determine the amount of memory that a system can address.
An example of this would be a system with a 32-bit address
bus can address 232 (4,294,967,296) memory locations. If
memory space is 4 GB.
A Data Bus is a computer subsystem that will allow for the
transferring of data from one component to another
motherboard or system board or two computers. This may
include transferring data to and from the memory or
transferring data from the CPU to other components within
the computer system. Each data bus is designed in a way to
handle many bits of data at one given time. The amount of
data that the data bus can handle is called the bandwidth.
In some small processors the data bus and
address bus will be combined into a single bus.
This is called multiplexing.

4

SIGN AND MAGNITUDE
There are many schemes for...