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Welcome students, I look forward to working with you this semester, check this site frequently for updates and assignments.

~  JON ~

Chapter 1 Notes

Chapter 2 Notes
Chapter 2 Notes/Images

Chapter 3 Notes
Chapter 4 Notes
Chapter 5 Notes
Chapter 6 Notes
Chapter 7 Notes
Chapter 8 Notes
Chapter 9 Notes
Port Identification

~ IST ~

Chapter 9

 

•   Computer switches

•                      Switches: Devices inside the computer that can be flipped between these two states: 1 or 0, on or off

•                      Nonmechanical devices in computers that open and close circuits

•                      Types of electrical switches:

•                      Vacuum tubes

•                      Transistors:

•                      Semiconductors

•                      Integrated circuits

•                      Binary number system

•                      Computers work in binary language

•                      Consists of two numbers: 0 and 1

•                      Everything a computer does is broken down into a series of 0s and 1s

•                      Inside the CPU

•                      The CPU Machine Cycle

•                      Fetch

•                      The program’s binary code is “fetched” from its temporary location in RAM and moved to the CPU

•                      Decode

•                      The program’s binary code is decoded into commands that the CPU understands.

•                      Execute

•                      The ALU performs the calculations.

•                      Store

•                      The results are stored in the registers

•                      System Clock

•              Located on the motherboard

•              Controls the CPU’s processing cycles

•              Clock cycle

•          Pulse or tick

•              Clock speed

•            Number of pulses per second

•          Measured in hertz (Hz)

•                      The CPU is the brains of the computer

•                      Different types of CPUs

•                      Intel and AMD chips: Used in most Windows-based PCs

•                      Apple systems use different CPU design

•                      Differentiating CPUs

•                      Processing power

•                      Clock speed and cache

•          The Algorithmic Logic Unit

•          Part of the CPU designed to perform mathematical operations (addition, subtraction, multiplication, division, etc.)

•          Also performs logical OR, AND, and NOT operations

•          Is fed data from the CPU registers

•          Word size: Number of bits a computer can work with at a time

 

•          The Control Unit

•          Manages the switches inside the CPU

•          Is programmed by CPU designers to remember the sequence of processing stages for that CPU

•          Moves each switch to its correct setting (on or off)

•          Then performs the work of that stage

 

•                      American Standard Code for Information Interchange (ASCII)

•                      8 bits = 1 byte = alphanumeric character or symbol

•                      256 different combinations

•                      Unicode

•                      16 bits equal 1 byte

•                      65,000 different combinations, used for all languages

•                      Cache Memory

•          Small amount of memory located on the CPU chip or near it

•          Stores recent or frequently used instructions and data

•          Used for quick access by the CPU

•          Different levels of cache

•                      Types of RAM

•          Volatile: When you turn off your computer, the data is erased

•          Several kinds of RAM exist

•          Each type of RAM has a different design

•          Some types work at much faster speeds

•          Some transfer data more quickly

•          Static RAM (SRAM)

•          Does not lose its electrical charge

•          Faster than DRAM

•          More expensive than DRAM

•          Used only in locations like cache memory

•          Dynamic RAM (DRAM)

•          Cheapest and most basic type of RAM

•          Loses its electrical charge

•          Needs to be refreshed

•          Many types of DRAM

•          SDRAM: Synchronous DRAM

•          DDR SDRAM: Double data rate SDRAM

•                      Computer buses

•          Electrical pathway used to move data between components

•          Local bus: Connects the CPU with the memory

•          Expansion bus: Connects the CPU with peripheral devices

•          Bus clock speed

•          Rate of speed data moves from one location to another

•          Measured in MHz (millions of clock cycles per second)

•          Bus width

•          The number of bits of data moved on a bus at any one time

•          Measured in bits

•          16 bits

•          32 bit

•                      Types of Buses

•          ISA and EISA

•          Found on older computers

•          Connects mouse, modem, and sound card

•          PCI

•          Faster than ISA and EISA

•          Found on modern computers

•          Connects network, modem, and sound cards

•          AGP

•          Used for three-dimensional graphics

•          Connects the graphics card and memory

•                      Creating faster CPUs

•          Pipelining: The CPU processes more than one instruction at a time

•          Dual processing

•          Two CPUs on the same system

•          Each processor shares the workload

•          Parallel processing

•          Network of computers

•          Each computer works on a portion of the problem simultaneously

•          Moores Law

•          Number of transistors on a CPU will double every 18 months

•          First chip had 29,000 transistors

•          Pentium chip 169,000,000 transistors

•          Moore’s Law has been accurate for more than 40 years

•          Law has remained accurate into the 21st century