2. Overview
All Computer components deal with at least
one of the following functions:
Input
Processing
Output
Storage
All of these components function together to
serve the user’s needs..
3. Input Devices
The keyboard and mouse are the most
commonly known input devices
Other input devices include multimedia inputs
such as:
Sound and voice inputs
Video inputs and
scanners
4. Input Devices
Cards and Ports: external components (keyboard, mouse, cameras,
microphones, musical instrument interfaces) connect to cards through the ports in the back of
each computer.
Keyboard and mouse cards
Video input cards
Sound and music cards
Voice Recognition devices
5. Input Devices
Input components connect to the “typical” AT or ATX
motherboard through ports in the back of the computer,
and PCI express slots, or an APG slot for graphics.
6. Input Devices
Hard drives, CD-ROMs,
floppy disk drives, and
“flash drives” can be
considered input devices,
too, because they store
information that can later
be retrieved by the
computer’s processor and
memory components
(more on processing and
storage devices later).
7. Processing
The motherboard connects all the computer’s electronic components
in order to function. It takes the input, processes the information
and/or commands, and renders an output. Below is a basic side-by-side
diagram of the locations of the input/output, processing, and memory
components on a PC.
The Central
Processing
Unit (CPU)
goes here.
This is con-
sidered the
computer’s
brain.
8. CPU & Memory
•The central processing unit (CPU) is often called
the brain or heart of the computer.
•It executes functions and directs the flow of
information.
•The CPU is made up of:
• the Control Unit, and,
•the Arithmetic/Logic unit.
9. Input/Output (the CPU)
The Control Unit
Controls the
“machine cycle”
It takes many cycles
to do even simple
calculations or
functions
The Arithmetic/Logic unit
Executes commands
as:
Arithmetic operations
(+,-,x,/), or
Logical comparisons
(>,<, =, not=)
10. Storage and Memory
The main memory interacts with the CPU in several ways. It is
made up of random access memory (RAM) chips, read and write
devices (like the hard drive, some CD and DVD drives, and “flash
drives”), and Read Only Memory devices (CD-ROM drives, or
other permanent storage devices).
•RAM chips (also called RAM cards, or integrated circuits) only store
information on a temporary basis– that is– while the computer is on.
•This is called volatile memory, because it is unstable and disappears
when the computer is turned off.
11. Machine Cycle (the CPU)
The control unit receives
input and translates to
computer commands
The ALU processes and
executes the command
The main memory stores and/or fetches information to
further execute the command, and returns information
to the control unit.
One cycle is completed.
12. Main Memory
CPU
RAM cards &
caches
Hard drive,
CD/DVD
Writer,
CD-ROM,
Floppy,
Flash drive
The main memory is the combination of various random access memory
devices, “read & write” devices, and some “read only” (ROM) devices.
The CPU interacts
With the main
Memory.
13. Processing (Motherboard)
The Motherboard makes input, processing, and output possible
by connecting all the components. Information is shared through
Busses. Busses are any “wires or cables” that transport information
between various components.
14. Storage Devices (RAM)
Random Access Memory means memory that is
temporary and can be stored in random cells.
Considered volatile and unstable
Memory is gone when computer is turned off.
RAM components have included RAM cards, SDRAM
Cards, and more.
15. Storage
The hard drive disc contains the operating
system and critical software programs to make
the computer function.
The hard drive includes a disk and the
hardware that turns, reads and writes to the
disk.
16. Storage
CD-ROM discs and drives
ROM stands for “read only memory”. This means
the memory is permanent and cannot be
changed.
Flash drives- the new “floppy discs”
Older storage devices included magnetic
floppy discs
19. References
Textual information
http://www.jegsworks.com
http://buildyourowncomputer.net
http://www.docstoc.com/docs/679377/How-do-
Computers-Work
Graphic Information
www.en.wikipedia.org/wiki/Personal_computer
www.en.wikipedia.org/wiki/Central_processing-
unit
Continued next slide
20. References
Graphic Information continued
Input devices from www.jegsworks.com
Hardware lessonPowerPoint
http://www.google.comr/#hl=en&source=hp&q=ha
rdware+lesson+ppt.
+and+cs1313&btnG=Google+Search&aq=f&aqi=
&aql=&oq=hardware+lesson+ppt.
+and+cs1313&gs_rfai=Cu_PkivUJTLDcF5-
yMZX6pcIKAAAAqgQFT9AHCLw&fp=88daed737
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Continued next slide
