- You saw the physical appearance of
a computer in the last webpage:
- The Functional/logical origanization
of a computer is as follows:
This architecture is known as:
- The von Neumann
architecture
(because it was first defined by John von Neumann in 1945)
Wikipedia page: click here
- The von Neumann
architecture
- A computer
consists of
4 types of
components:
- The Central Processing Unit (CPU) --- also known as a processor.
- Memory (a.k.a. Random Access Memory (RAM)
- Input devices (e.g., mouse, key board, scanner, disks...)
- Output devices (e.g., terminal, printer, disks, ...)
- The components in a
computer can be grouped
into 2 categories
according to their
function:
- The Computer System
(the core system)
- The Central Processing Unit (CPU) --- also known as a processor.
- Memory (a.k.a. Random Access Memory (RAM)
The computer system performs the main (computational) function of the computer
- Peripheral devices
(a.k.a.: Input/output devices)
- Input devices (e.g., mouse, key board, scanner, disks...)
- Output devices (e.g., terminal, printer, disks, ...)
Peripheral devices are auxiliary devices that allow users to:
- Enter inputs into the computer
- Obtain outputs from the computer
Peripheral devices do not perform computations....
- The Computer System
(the core system)
- Function of the
CPU:
- The CPU will fetch the next instructions in a program from the memory and execute the (fetched) instruction
- Function of the
computer memory (RAM):
- The memory
is a huge storage component that
stores:
- Instructions of computer programs
- Variables (= data) used in the computer programs
- The CPU can
retrieve (= read)
instructions from
the computer memory
and execute them
The CPU can also retrieve (= read) and store (= write) data from/to the computer memory
- The memory
is a huge storage component that
stores:
- Function of
input devices:
- Enables human users
to enter data
into the computer (= machine)
Important:
- The data will be stored inside the computer in such a way that the computer can use it effectively.
- There many different forms of inputs: text (keyboard), pointing (mouse), graphics (scanner), stored information (disk files), etc.
- Enables human users
to enter data
into the computer (= machine)
- Function of
output devices:
- Enables the computer to
show data stored inside the computer
to a human user
in a "humanly" way
- There are many different forms of outputs: text (terminal), audio (speakers), visual (graphic displays), ..., etc.
- Enables the computer to
show data stored inside the computer
to a human user
in a "humanly" way