CS271 ASSEMBLY LANGUAGE PROGRAMMING - PowerPoint PPT Presentation

CS271ASSEMBLY LANGUAGE PROGRAMMING

Class hour: 9:30-10:45 am TR.

Hyer Hall Room 210

• Identify the major component of a PC-based system, describe the steps involving in assembling, linking, and executing a program
• Write/Debug programs in assembly language to perform the given task and run them

Textbook:

IBM PC Assembly Language and Programming. Peter Abel. 2001. Fifth Edition. Prentice Hall. ISBN: 0-13-030655-X

Software:

Emu8086 microprocessor assembler and emulator software. Available at www.emu8086.com

Tell me about yourself and what you expect to get out from this course

• Recently graduated from the University of Connecticut (05 Class), Ph.D in Computer Science and Engineering

• Master of Computer Science from UW-Milwaukee (96-99)

• Bachelor of Science from Hanoi University of Technology (86-91)

• Research Experience:
• User Modeling, Information Retrieval, Decision Theory, Collaborative Filtering, Human Factors
• Teaching Experience:
• CS 271,172, and 181 at UWW (Fall 2005)
• Introduction courses at UOP and Devry
• TA for Computer Architecture, OO Design, Compiler, Artificial Intelligence

• Teaching philosophy:
• Interactive
• Adaptive
• Pro-active
• Collaborative
• Other hobbies (non-academic related)
• Movies
• College Basketball
• Family activities

nguyenh@uww.edu

Baker Hall 324

Office Hours: 2:15-4:15MWF or by appointment

262 472 5170

Write

a program

in assembly language

Understanding

of a PC-based

system

Fundamentals of

assembly

language & program

Specific

Applications

• Attend the class regularly and actively participate
• in the class discussion (ask questions, answer
• questions, etc..)
• Don’t give up on programming assignments.
• Pay attention to detail
• Try many options when doing programming
• assignments

• Binary and Hexadecimal Number Systems
• Bits/bytes
• Binary number systems
• Hexadecimal
• ASCII
• PC Components
• Processor
• Memory

• Bits: 0(off) & 1(on)
• Bytes:
• Represents a storage location in memory and devices.
• 8 bits => 28 combination of 0/1.

Address

40 Husky Road

Storrs, CT 06329

00000100 00000000

Word

Doubleword

Quadword

Paragraph

Kilobyte

Megabyte

Bit value

Position value

Bit number

0+0=0

1+1=10

1+0=1

01010101

10101010

Add 1

10101011

Operations

Negative binary numbers

2’s complement’s notation

Reverse the bit values and add 1

1. What is the value of 01010101?

2. How to represent -25 in 2’s complement

notation?

Bit value

Position value

Bit number

Parity bit: forcing the number of bits always odd

Example: 01010101

Parity bit = 1

00010101

Parity bit = 0

• Disadvantage of binary representation:
• Is not “user-friendly”
• Complicated when computing manually
• Hexadecimal representation

Hexadecimal arithmetic

7+1=8

7+2=9

7+3=A

7+4=B

7+8=F

7+9=?

• Convert from decimal to hexadecimal

23 = ????

254 = ????

• Adding hexadecimal value

13B4H + 0033H = ????

DCBEH + 35B5H = ????

• ASCII—American Standard Code for Information Interchange
• EBCDIC—Extended Binary Coded Decimal Interchange Code
• Unicode—coding scheme capable of representing all world’s languages

Step 1.The user presses the capital letter D (shift+D key) on the keyboard.

Step 4.After processing, the binary code for the capital letter D is converted to an image, and displayed on the output device.

Conversion from letter to binary format and back

Step 2.An electronic signal for the capital letter D is sent to the system unit.

Step 3.The signal for the capital letter D is converted to its ASCII binary code (01000100) and is stored in memory for processing.

Question?

system unit

PC camera

speaker

printer

monitor

keyboard

modem

scanner

mouse

microphone

digital camera

speaker

• What are two main components on the motherboard?

• Central Processing Unit (CPU)
• Also called a processor
• Carries out instructions that tell computer what to do

• Memory
• Temporary holding place for data and instructions

Processor

Control Unit

Arithmetic Logic Unit (ALU)

Control Unit

Arithmetic Logic Unit (ALU)

InstructionsDataInformation

InstructionsDataInformation

Memory

InputDevices

OutputDevices

Data

Information

StorageDevices

Central processing unit (CPU) (Processor)

• Interprets and carries out basic instructions that operate a computer

• Control unit directs and coordinates operations in computer

• Arithmetic logic unit (ALU) performs arithmetic, comparison, and logical operations

Operating system

Data

• Temporary storage place for data, instructions, and information
• Consists of one or more chips on the motherboard or some other circuit board

Applications

• Three basic items stored in memory

• Size of memory is measured by the number of bytes available
• Kilobyte - 1,024 bytes
• Megabyte – approximate one million bytes

Volatile Memory

Loses its contents when the computer's power is turned off

volatile memory

Loses its contents when the computer's power is turned off

nonvolatile memory

Does not lose its contents when the computer’s power is turned off

What are the two types of memory in the system unit?

Memory chips that can be read from and written to by the processor and other devices

When the computer starts, operating system files are loaded from a hard disk into RAM

As additional programs and data are requested, they also load from storage into RAM

Most RAM is volatile

What is random access memory (RAM)?

• Difference between address of a memory
• Location and its content
• Processor stores the data in memory in
• reverse by sequence
• Two types of addressing schemes
• absolute address
• segment-offset address

• Code segment (CS)
• Data segment (DS)
• Stack segment (SS)
• Extra segment (ES)
• Actual address = segment address + offset

• Segment register
• CS,DS,SS,ES, FS and GS
• Pointer register
• IP,SP,BP
• General purpose register
• AX,BX,CX,DX
• Index register
• SI, DI

OF, DF, IF, SF, ZF,AF,PF,CF

If cleared: NV,UP,EI,PL,NZ,NA,PO,NC

If set: OV,DN,EI,NG,ZR,AC,PE,CY