Chapter 1Data Storage(1)

Yonsei University

1st Semester, 2015 Sanghyun Park

Outline Bits and their storage Main memory Mass storage (next file) Representing information as bit patterns (next file) Binary system (next file) Storing integers (next file) Storing fractions (next file)

Bits and Their Storage Today’s computers represent information as patterns of

____

A bit (binary digit) is either one of two _____ – 0 and 1

Storing a bit within a machine requires a device that can be in one of two ______, such as a switch (on or off) ora relay (open or closed)

Bit Operations

Gates (1/3) We think of the digit 0 as representing the value _____

and the digit 1 representing the value ____

Operations that manipulate true/false values are called ________ operations

A device that produces the output of a Boolean operation is called a ____

Gates (2/3) Gates can be constructed from a variety of technologies

such as gears, relays and optic devices

Current technology implements gates as small electronic _______

Gates are building ______ from which computers are constructed

Gates (3/3)

Flip-Flop Circuit (set of connected _____) whose output will flip or

flop between ___ values under control of external stimuli

Flip-flop can be used to store value of a ___

Flip-Flop Output If both inputs are 0, output will ___ ______

Placing 1 on _____ input forces output to be 1

Placing 1 on _____ input forces output to be 0

Setting the Output to 1 (1/3)

Setting the Output to 1 (2/3)

Setting the Output to 1 (3/3)

Another Way of Constructing Flip-Flop

Hexadecimal Notation Long bit streams are difficult to make sense of

The lengths of most bit streams used in a machine are multiples of _____

____________ notation is a shorthand notation for streams of bits

Hexadecimal notation is more ________, and_____ ___________ to manually read, copy, or write

Hexadecimal Coding System

Main Memory: Cells Cells are manageable units (typically _ bits) into which a

computer’s main memory is arranged

A _____ is a string of 8 bits

The left end of the conceptual row in which the contents of a cell are laid out is called the ________ end

The right end of the conceptual row in which the contents of a cell are laid out is called the _______ end

The bit at the low-order end is called the ___ significant bit

Byte-Size Memory Cell

Main Memory Addresses An _______ is a “name” to uniquely identify one cell in

the computer’s main memory

Addresses are __________ numbers, usually starting at ____

Cells have an _____: “previous cell” and “next cell” have reasonable meanings

Memory where any cell can be accessed independently is called _______ access memory

Memory Cells Arranged By Address

Measuring Memory Capacity “_____” normally means 1,000;

Kilobyte = 210 = 1,024

“_____” normally means 1,000,000;Megabyte = 220 = 1,048,576

“_____” normally means 1,000,000,000;Gigabyte = 230 = 1,073,741,824