Computer Organization & Assembly Language Lecture # 9 By Muhammad Jafer

Quiz (15-15) What is pipelining. How inlet Implemented pipelining Calculate Physical Address for each instructions. What will be the value of AX, AH, AL, IP & CS after executing the last instruction Logical Address CS:IP Assembly Language 1ABC:0000 MOV AX, 99D xxxx:0100 ADD Al,A2 xxxx:010A SUB Al,02 xxxx:0200 ADD AX,FF10

STACK Temporary memory for Processors Stored in RAM Importance & alternate of Register-Register Design Every Register can be stored except SS&SP Logical Addresses VS Physical Addresses SS:SP Overlapping Intel Architecture Stack Increments and then add Show & decrement Stack Pointer

Flag Registers Conditional Flags CF PF AF ZF SF OF Control Flags TF IF DF

X86 Addressing Modes Register Address Mode MOV BX,DX Immediate Mode MOV AX,2550H Direct Mode MOV AX,[2550] Register Indirect Addressing Mode MOV AL,[BX] Based Relative Addressing Mode MOV CX,[BX]+10 Based Index Addressing Mode MOV CX,[BX][DX]+10 Segment Overrides

Chapter Review The x86 PC Assembly Language, Design & Interfacing by Muhammad Ali Mazidi, Janice Gillispie Mazidi & Danny Causey Chapter # 1 The Stack Flag Registers X86 Addressing Modes

Assembly Program Concepts [label:] mnemonic [operands] [;comments] Mnemoics can be directives Directive give direction to assembler Assembly Program Model Definition Segment Definition .STACK .DATA .CODE

MODEL DEFINITION .MODEL SMALL How much space is required MEDIUM >64k for memory COMPACT >64k for data LARGE >64k for both but one at a time HUGE >64k for both at same time TINY >COM File concepts (Will not be used in this course)

Segmentation DEFINITION Can work with only one segment. Good programing practices .STACK 64k .DATA [label/Name] [length] [values] DATA1 DB 55H DATA2 DW ? .CODE MOVE DS,@DATA

Chapter Review The x86 PC Assembly Language, Design & Interfacing by Muhammad Ali Mazidi, Janice Gillispie Mazidi & Danny Causey Chapter # 2 Directives & A Sample Program