1. Prof . Ki-Dong Chung Pusan Nat’l University kdchung@pusan.ac.kr
System Software
Prof . Ki-Dong Chung
Pusan Nat’l University

2. System software Text 참고교재 한국어판 : 시스템 소프트웨어
홍릉과학출판사(2007), 유원희 외 2명
참고교재
System Software:An Introduction to Systems Programming
Leland L. Beck

3. System program 강의 내용 제1-3주: Assembly 프로그래밍
제4-6주: Assembly 프로그래밍과 Assembler
제7주: Loaders and linkers
제 8주 : 중간고사
제9주: Macro Processor
제 10-11주: Compiler
제 12-13주: 운영체제
제 14주: Software 공학
제 15주: 기말고사

4. System program 평가 참고 사항 추가 시험 없음미응시자는 과락 재수강을 위한 학점 변경 불가 강의노트
Mid-term exam %
Final-term exam %
Term/Report %
출석 %
퀴즈 %
참고 사항
추가 시험 없음미응시자는 과락
재수강을 위한 학점 변경 불가
강의노트

5. Computer system Hardware system Software system CPU Memory I/O devices
Application software
System software

6. System software System software ? H/W와 S/W사이의 Gap 존재
Resource Optimization
다양한 사용자 요구 수용
Multimedia data
Video
Audio
Graphics
Text
Ubiquitous computing
다양한 N/W
다양한 device들

7. System software • Environment제공  효율적인 사용자 Interface
- Program execution
- Access to I/O devices
- Controlled access to files
- System access;
 whole system or specific resources
 protection, unauthorized access, resolve conflicts
- Error detection and response
- Accounting
• Efficiency: Resource manager
- Memory: OS S/W(kernel), Program, Data
- Processor
- I/O controller/devices

8. System software
1. Types
- Language Processor : Compiler, Interpreter, Assembler, Macro processor
- Operating System
- Loader/Linker
- DBMS
- Utility Programs
2. 특징
- Machine Dependent
- Large Volume
- Performance 고려
- 분산처리/병렬처리/멀티미디어 수용/Realtime 수용

9. 2. SIC (Simplified Instructional Computer)
SIC :Standard Model
SIC /XE(Extra Equipment)
Virtual memory
Concurrency
Indirect I/O
Upward compatible
SI C 프로그램이 SI C /XE에서 실행 가능
1. SIC :Hypothetical computer
1) Memory:
- Byte addressing/word(3byte)/215 = 32KB addressing space

10. 2. SIC(Simplified Instructional Computer)
2) Registers
- A:Accumulator
- X:Index register  Indexed addressing
- L:Linkage register  Return address(JSUB instruction)
- PC:Program Counter  Next instruction to be fetched for execution
- SW:Status Word  Condition Code, Interrupt Code

11. 2. SIC(Simplified Instructional Computer)
3) Data format
- 2's complement/ASCII code/No floating point H/W
4) Instruction format
5) Addressing mode
- Direct addressing x=0 TA(Target Address) = address
- Indexed addressing x=1 TA = address + (x)

12. 2. SIC(Simplified Instructional Computer)
6) Instruction set
Load/Store
Arithmetic operations
C ompare instruction
Jump instruction
JSUB/RSUB
7) I/O:Direct I/O  Polling
- TD(Test Device): '=' Not ready/'<' Ready
- RD(Read)/WD(Write)

13. 2. SIC (Simplified Instructional Computer)
2. SIC / XE
1) Memory:1MB(220 = 1MB)
2) Registers
- B:Base register  Virtual Memory
- S:General register  I/O용
- T:General register  Synchronization용
- F:Floating point registers
3) Data format
- Floating point number지원

14. 2. SIC(Simplified Instructional Computer)
4)Instruction format
(1) Format1(1byte)
(2) Format2(2byte)
(3) Format3(3byte)
(4) Format4(4byte)

15. 2. SIC(Simplified Instructional Computer)
5) Addressing mode
(1) Base relative b=1,p=0 TA=(B) + disp(0 disp 4095)
(2) PC relative b=0,p=1 TA=(PC) + disp
(3) Direct addressing b=p=0(b,p,e는 address의 일부로 간주)
(4) Indirct addressing i=0,n=1
(5) Immediate addressing: i=1,n=0
(6) Simple addressing:i=n=1->neither immediate nor indirect
6) Instruction set
- LDB/STB
- ADDR/SUBR/MULR/DIVR
- SVC(Supervisor call)
7) I/O:Indirect I/O
- SIO/HIO/TIO

16. Assembly programming Machine language Assembly language
Low level language
Binary representation
Assembly language
Symbolic language
Assembly source program  Assembler  Machine language object program
Assembler:Translator
High level source program  Compiler  Low level object program

17. Instruction set Description Uppercase letters : specific register
m : memory address
n : integer between 1 and 16
r1, r2 : register identifier
ex) A  (m..m+2) means m through m+2 are loaded into register A
* Registers
Mnemonic
Number
Special use A
Accumulator;used for arithmetic operation X 1
Index register; used for addressing L 2
Linkage register; the Jump to Subroutine(JSUB)
Instruction stores the return address in this register PC 8
Program counter; contains the address of the next instruction to be fetched for execution SW 9
Status word; contains a variety of information, including a Condition Code(CC)

18. Instruction set Load & Store register operation
Mnemonic format Opcode effect
LDA m 3,4 00 A (m..m+2)
LDA FIVE
LDX m 3,4 04 X (m..m+2)
LDX ONE
STA m 3,4 0C m..m+2  (A)
STA ONE
STX m 3,4 10 m..m+2  (X)
STX TWO

19. Instruction set Arithmetic operation Mnemonic format Opcode effect
ADD m 3, A (A) +(m..m+2)
ADD SEVEN
SUB m , C A (A) – (m..m+2)
SUB ONE
DIV m , A (A)/(m..m+2)
DIV TWO
MUL m 3, A (A) * (m..m+2)
MUL TWO

20. Instruction set Conditional jump instruction
Mnemonic format Opcode effect
COMP m 3,4 28 (A) : (m..m+2)
Compare the value in register A with a word in memory
This instruction sets a condition code CC
COMP FIVE
JLT m 3,4 38 PC  m if CC set to <
JLT LOOP
JEQ m ,4 30 P C  m If CC set to =
JEQ EXIT
JGT m ,4 34 PC  m if CC set to >
JGT LOOP