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

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

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

System program 평가 참고 사항 추가 시험 없음미응시자는 과락 재수강을 위한 학점 변경 불가 강의노트 Mid-term exam 30% Final-term exam 40% Term/Report 20% 출석 5% 퀴즈 5% 참고 사항 추가 시험 없음미응시자는 과락 재수강을 위한 학점 변경 불가 강의노트 http://apple.cs.pusan.ac.kr

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

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

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

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

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

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

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)

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)

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

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

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

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

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)

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

Instruction set Arithmetic operation Mnemonic format Opcode effect ADD m 3,4 18 A (A) +(m..m+2) ADD SEVEN SUB m 3,4 1C A (A) – (m..m+2) SUB ONE DIV m 3,4 24 A (A)/(m..m+2) DIV TWO MUL m 3,4 20 A (A) * (m..m+2) MUL TWO

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 3,4 30 P C  m If CC set to = JEQ EXIT JGT m 3,4 34 PC  m if CC set to > JGT LOOP