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Computer image - Coggle Diagram
Computer
Bus System
Features
Bus width
is the number of bit that it can transfer at a time
The limitation of bus is only one transmission at a time
Speed
of a bus is measured in megahertz(
MHz
)
Definition
A collection of
wires
or
electrical pathways
through which
data is transmitted
Types
System Bus
(Internal Bus)
Definition
Collection of buses work together
within a computer system
Types
Address Bus
Carries memory addresses from the CPU to memory, specifying the location of data to be read from or written to
Unidirectional
Width of an address bus
->
determine the
capacity of a main memory
Data Bus
Sends the actual data to and from the memory
Bidirectional
Width of a data bus
->
determine the
word length of a CPU
Control Bus
Used to carry the control signals and timing signals
Timing Signals are used to synchronize the memory and IO operations with a CPU clock.
Control signals indicate the type of operation
Controlling Address Bus and Data Bus
Bidirectional
I/O Bus
(External)
Definition
(Peripheral bus)
Data pathway that connects
peripheral devices
to the CPU
(such as the keyboard, mouse, display, and storage devices)
The I/0 buses differ from the system bus in speed. Their
speed will always be lower than the system bus speed.
Types
PCI
PCIe
ISA
USB
SATA
PATA
Ethernet
....
CPU
Function
Instruction Execution:
The CPU fetches instructions from the computer's memory,
decodes them, and executes the necessary operations.
Arithmetic and Logic Operations:
The CPU performs various arithmetic operations, including addition, subtraction, multiplication, and division. It also executes logical operations such as AND, OR, NOT, and XOR
Control Unit:
The CPU contains a control unit that coordinates and manages the execution of instructions. It controls the flow of data and instructions within the CPU and between the CPU and other components of the computer system.
Instruction Pipelining:
To improve performance, modern CPUs use a technique called instruction pipelining. It breaks down the execution of instructions into a series of stages, allowing multiple instructions to be processed simultaneously.
Memory Management:
The CPU interacts with the computer's memory to read data and instructions from it and write the results back.
Cache Management
CPUs often have multiple levels of cache memory, which are small and fast memory units used to store frequently accessed data.
Types
Desktop CPUs:
x86 CPUs
AMD
Intel
Server CPUs
Intel Xeon
AMD EPYC
Mobile CPUs:
ARM CPUs (Advanced RISC Machines)
Intel
AMD
Defition
is the brain of the computer
processes all the commands that the CPU receives from hardware and software
Process computer programs and computer input data
I/O Module
I/O Device
Type of I/O Devices
Input device
Send the data from user or others program to computer. At the end of the process is CPU
Both Input and Output device
Output device
Send the data from computer to user or others program.
Definition
Allow user to interact with a computer
delivery and receiving data from a computer.
Definition
manage the communication between a CPU and a network
the transfer of data
the management of power loads
the control of machine functions.
Function
Control and Timing
:one: CPU asks module to check status of attached
devices
:two: Module tells the status
:three: CPU request for data transfer to module if
device is ready
:four: Module gathers the data and transfer to CPU
CPU Communication
:one: Command decoding (read/write)
:two: Data (exchange between CPU and module)
:three: Status reporting (to CPU since peripherals is
slow)
:four: Address recognition for the devices connected
to it
Device Communication
:arrow_right: Involves command,status information and data transfer
Error Detection
:arrow_right: Paper jam or bad data
Data Buffering
:arrow_right: Essential function to overcome speed mismatch
Memory
Primary Memory
Cache memory
Cache memory is a small but extremely fast memory located on the CPU chip or in close proximity to it
Random Access Memory (RAM)
RAM is the main form of primary memory in a computer system.
Read-Only Memory (ROM)
ROM is non-volatile memory that contains permanent instructions or data.
Secondary Memory
SSD
SSD is a non-volatile storage device that uses flash memory technology to store data.
HHD
HDD is a non-volatile storage device that uses magnetic storage to store data
Optical Drives
Use optical storage media to store and retrieve data
Virtual Memory
Virtual memory is a technique that allows the computer to use secondary storage as an extension of primary memory.
Memory Hierarchy
Computer systems often employ a memory hierarchy that consists of multiple levels of memory.
