Chapter 1Data Storage(2)
Yonsei University
1st Semester, 2014 Sanghyun Park
Outline Bits and their storage (prev. file) Main memory (prev. file) Mass storage Representing information as bit patterns Binary system Storing integers (next file) Storing fractions (next file)
Mass Storage Systems Non-volatile; data _______ when power is off
Usually much ______ than main memory
Usually _______ disks Hard disk, floppy disk, CD-ROM Much ______ than main memory because
(1) data access must wait for _____ time (head positioning), and(2) data access must wait for ________ latency
Disk Storage
CD Storage
Magnetic Tape Storage
Representing Text ASCII (adopted by American National Standards Institute
ANSI) American Standard Code for Information Interchange _____ to represent each symbol Upper and lower case letters of English alphabet,
punctuation symbols, digits 0 to 9, and other symbols Can represent 256 (28) different symbols
Unicode _____ to represent each symbol Can represent 65,536 (216) different symbols
ISO (International Organization for Standardization) _____ to represent each symbol Can represent more than 17 million symbols
Representing Numeric Values Binary notation –
uses bits to represent a number in base ____
Limitationsof computer representations of numeric values ________ happens when a number is too big to be represented _________ happens when a number is between two
representable numbers
Representing Images Bitmap techniques
Image is a collection of ______ (picture element) Each pixel can be represented as a number of bits
1 bit/pixel Black and white8 bits/pixel Gray scale24 bits/pixel 1-byte for each of the primary colors RGB
Size? (need for ___________)
Vector techniques Image represented as collection of _____ and curves Fonts on printers _______ fonts (True Type, PostScript) CAD (Computer Aided Design) _______ problem
Representing Sound
Base Ten and Base Two Systems
Decoding the Binary Representation
Finding Binary Representation ofPositive Integers
Finding Binary Representationof Thirteen
Binary Addition Facts
Fractions in Binary (1/3) Use _____ point just like decimal To the _____ of radix point positions are numbered
as -1, -2, -3, …
Fractions in Binary (2/3) Express the following binary notation
Convert the integer part Convert the fraction part;
Try to map the fraction as a sum of ___________________using the given ___________ as a guide.
Put a radix point in between
1653
310 is 112
20101.041
161
164
161
165
20101.111653
Fractions in Binary (3/3) Addition of binary numbers with radix points
_____ radix point Apply binary addition process
0010.011
+ 100.110
0111.001