This document provides an overview of basic computer architecture. It discusses the history of computers, components like the CPU, motherboard, and connections between parts. The document outlines CPU architecture including the fetch-decode-execute cycle and components like the ALU, control unit, and registers. It also describes memory, addressing, cache, and different memory types like RAM, ROM, and CMOS.

1. Basic Computer
Architecture
Yong Heui Cho @ Mokwon University

2. 2
Basic Computer Design
1. History of Computers
2. Introduction to Arduino
3. Basic Computer Architecture
4. Combinational Logic Circuit

3. 3
Computer Components
• Input/output units
• Memory/storage units
• CPU (Central Processing Unit)

4. 4
Motherboard Diagram
• Northbridge
– Connected to CPU in high
speed
• Southbridge
– Connected in low speed
• Bus
– Related to “omnibus”
– Communication system
between components

5. 5
Computer System

6. 6
Connection of Components
Northbridge
South
bridge

7. 7
CPU Architecture

8. 8
von Neumann Architecture

9. 9
Harvard Architecture

10. 10
CPU: 3 Major Components
• ALU (Arithmetic Logic Unit)
– Performs calculations and comparisons (data changed)
• CU (Control Unit): performs fetch/execute cycle
– Functions:
• Moves data to and from CPU registers and other hardware comp
onents (no change in data)
• Accesses program instructions and issues commands to the ALU
– Subparts:
• Memory management unit: supervises fetching instructions and d
ata
• I/O Interface: sometimes combined with memory management u
nit as Bust Interface Unit
• Registers
– Example: Program Counter (PC) or instruction pointer determi
nes next instruction for execution
□ Courtesy to Basic Computer Architecture, slideshare.

11. 11
Machine Cycle
• Fetch-decode-execute-store

12. 12
Concept of Registers
• Small, permanent storage locations withi
n the CPU used for a particular purpose
• Manipulated directly by the CU
• Wired for specific function
• Size in bits or bytes (not MB like memor
y)
• Can hold data, an address or an instructi
on
□ Courtesy to Basic Computer Architecture, slideshare.

13. 13
Register Operations
• Stores values from other locations (regist
ers and memory)
• Addition and subtraction
• Shift or rotate data
• Test contents for conditions such as zero
or positive
□ Courtesy to Basic Computer Architecture, slideshare.

14. 14
Registers in CPU
• Program
Counter (PC)
register
• Instruction
Register (IR)
• Status register:
status, flags

15. 15
Cache Memory
• Cache level
– L1 cache: fastest and smallest
– L2 cache: next fastest and smallest

16. 16
Operation of Memory
• Each memory location has a unique addr
ess
• Address from an instruction is copied to
the MAR (Memory Address Register) whi
ch finds the location in memory
• CPU determines if it is a store or retrieval
• Transfer takes place between the MDR (
Memory Data Register) and memory
• MDR is a two way register
□ Courtesy to Basic Computer Architecture, slideshare.

17. 17
MAR, MDR, Memory
Address Data
□ Courtesy to Basic Computer Architecture, slideshare.

18. 18
MAR-MDR Example
□ Courtesy to Basic Computer Architecture, slideshare.

19. 19
Individual Memory Cell
□ Courtesy to Basic Computer Architecture, slideshare.

20. 20
Memory Capacity
• Determined by two factors
1. Number of bits in the MAR
• 2K where K = width of the register in bits
2. Size of the address portion of the instruction
• 4 bits allows 16 locations
• 8 bits allows 256 locations
• 32 bits allows 4,294,967,296 or 4 GB
• Important for performance
– Insufficient memory can cause a processor to w
ork at 50% below performance
□ Courtesy to Basic Computer Architecture, slideshare.

21. 21
Random Access Memory
• DRAM (Dynamic RAM)
– Most common, cheap
– Volatile: must be refreshed (recharged with pow
er) 1000’s of times each second
• SRAM (Static RAM)
– Faster than DRAM and more expensive than DR
AM
– Volatile
– Frequently small amount used in cache memory
for high-speed access used
□ Courtesy to Basic Computer Architecture, slideshare.

22. 22
Read Only Memory
• Non-volatile memory to hold software th
at is not expected to change over the life
of the system
• Magnetic core memory
• EEPROM
– Electrically Erasable Programmable ROM
– Slower and less flexible than Flash ROM
• Flash ROM
– Faster than disks but more expensive
– Uses
• BIOS: initial boot instructions and diagnostics
• Digital cameras
□ Courtesy to Basic Computer Architecture, slideshare.

23. 23
CMOS Memory
• CMOS (Complimentary Metal Oxide
Semiconductor) TR (Transistor)
– Low power consumption, cheap TR
• BIOS (Basic I/O System) and system
settings that users can change

24. 24
Arduino: 직렬 통신으로 문자 받기

25. 25
Arduino: 기계 엡실론 구하기