1. Princess Sumaya Univ. Computer Engineering Dept. Chapter 4:

2. Princess Sumaya University 22342 – Computer Org. & Assembly Lang. Computer Engineering Dept. 1 / 20 Direct Data Transfers  Immediate Operands ●Constant Values ●Exclude Segment Registers Example:

3. Princess Sumaya University 22342 – Computer Org. & Assembly Lang. Computer Engineering Dept. 2 / 20 Direct Data Transfers  Direct Memory Addressing ●Numerical Value ●Variable Name Example: Memory 0000 0001 0002 0003 0004 0005 Program File.Data DB0 CountDB5 SUMDW1234h.Code END

4. Princess Sumaya University 22342 – Computer Org. & Assembly Lang. Computer Engineering Dept. 3 / 20 Direct Data Transfers  MOV Instruction ●MOVreg, reg ●MOVmem, reg ●MOVreg, mem ●MOVmem, imm ●MOVreg, imm ●MOVreg, sreg ●MOVsreg, reg ●MOVmem, sreg ●MOVsreg, mem

5. Princess Sumaya University 22342 – Computer Org. & Assembly Lang. Computer Engineering Dept. 4 / 20 Direct Data Transfers  XCHG Instruction ●XCHGreg, reg ●XCHGreg, mem ●XCHGmem, reg

6. Princess Sumaya University 22342 – Computer Org. & Assembly Lang. Computer Engineering Dept. 5 / 20 Direct Data Transfers  Direct-Offset Memory Addressing ●Effective Address Example: Memory 0000 0001 0002 0003 0004 0005 Program File.Data Grades DB0 DB0 Profits DW0 DW0 END

7. Princess Sumaya University 22342 – Computer Org. & Assembly Lang. Computer Engineering Dept. 6 / 20 Increment & Decrement  INC and DEC Instructions ●INCreg ●INCmem ●DECreg ●DECmem Program File.Data Var1 DB5 DB6 DB7 Var2 DW1 Var3 DW2 Var4 DW3 END

8. Princess Sumaya University 22342 – Computer Org. & Assembly Lang. Computer Engineering Dept. 7 / 20 Addition  ADD Instruction ●ADDreg, reg ●ADDreg, mem ●ADDreg, imm ●ADDmem, reg ●ADDmem, imm Program File.Data Var1 DB5 DB6 DB7 Var2 DW1 DW2 DW3 END

9. Princess Sumaya University 22342 – Computer Org. & Assembly Lang. Computer Engineering Dept. 8 / 20 Subtraction  SUB Instruction ●SUBreg, reg ●SUBreg, mem ●SUBreg, imm ●SUBmem, reg ●SUBmem, imm  NEG Instruction ●NEGreg ●NEGmem Program File.Data Var1 DB5 DB6 DB7 Var2 DW1 DW2 DW3 END

10. Princess Sumaya University 22342 – Computer Org. & Assembly Lang. Computer Engineering Dept. 9 / 20 Implementing Arithmetic Expressions Example: Result = - X + (Y – Z) Program File.Data X DW5 Y DW6 Z DW7 Result DW1 DW2 DW3 END

11. Princess Sumaya University 22342 – Computer Org. & Assembly Lang. Computer Engineering Dept. 10 / 20 Flags After Arithmetic Operations  INC and DEC Instructions ●Zero Flag ●Sign Flag Program File.Data Var1 DB- 1 DB0 DB7Fh Var2 DW1 Var3 DW2 Var4 DW3 END

12. Princess Sumaya University 22342 – Computer Org. & Assembly Lang. Computer Engineering Dept. 11 / 20 Flags After Arithmetic Operations  ADD and SUB Instructions ●Zero Flag ●Sign Flag ●Carry (Borrow) Flag ●Overflow Flag Program File.Data Var1 DB- 1 DB1 DB7Fh Var2 DW1 Var3 DW2 Var4 DW3 END

13. Princess Sumaya University 22342 – Computer Org. & Assembly Lang. Computer Engineering Dept. 12 / 20 Flags After Arithmetic Operations  NEG Instruction ●Zero Flag ●Sign Flag ●Carry (Borrow) Flag ●Overflow Flag Program File.Data Var1 DB- 1 DB1 DB7Fh Var2 DW1 Var3 DW2 Var4 DW3 END

14. Princess Sumaya University 22342 – Computer Org. & Assembly Lang. Computer Engineering Dept. 13 / 20 Indirect Addressing  Indirect Memory Addressing ●SI, DI, BX Example: Memory 0000 0001 0002 0003 0004 0005 Program File.Data T DB5 DB7 DB2 V DW8 DW3 DW4 END

15. Princess Sumaya University 22342 – Computer Org. & Assembly Lang. Computer Engineering Dept. 14 / 20 Indirect Addressing Array Example: Var1 = Σ Array1 Program File.Data Array1 DB5 DB6 DB7 Var1 DB0 Var2 DW0 Var3 DW0 END

16. Princess Sumaya University 22342 – Computer Org. & Assembly Lang. Computer Engineering Dept. 15 / 20 Indirect Addressing  Indexed Memory Addressing ●Constant + Pointer Example: Memory 0000 0001 0002 0003 0004 0005 Program File.Data X DB10 DB11 DB12 Y DW20 DW21 DW22 END

17. Princess Sumaya University 22342 – Computer Org. & Assembly Lang. Computer Engineering Dept. 16 / 20 Indirect Addressing  Base-Index Memory Addressing ●BX + (SI or DI) Example: Memory 0000 0001 0002 0003 0004 0005 Program File.Data Array1 DB11 DB12 DB13 DB21 DB22 DB23 END Array1 111213 212223 313233

18. Princess Sumaya University 22342 – Computer Org. & Assembly Lang. Computer Engineering Dept. 17 / 20 Transferring Control  Unconditional Transfer ●Jump ●Call Routine ●Return Example:

19. Princess Sumaya University 22342 – Computer Org. & Assembly Lang. Computer Engineering Dept. 18 / 20 Transferring Control  Conditional Transfer ●Jump on Condition Example:

20. Princess Sumaya University 22342 – Computer Org. & Assembly Lang. Computer Engineering Dept. 19 / 20 Transferring Control  Conditional Transfer ●Repeat a number of times Example:

21. Princess Sumaya University 22342 – Computer Org. & Assembly Lang. Computer Engineering Dept. 20 / 20 Transferring Control  Conditional Transfer ●Repeat While (Another Chapter)

22. Princess Sumaya University 22342 – Computer Org. & Assembly Lang. Computer Engineering Dept. Chapter 4