Joseph L. Lindo Assembly Programming Sir Joseph Lindo University of the Cordilleras

Joseph L. Lindo Data + and - Section 1 Assembly Programming Registers Named storage locations inside the CPU, optimized for speed. High speed storage locations directly inside the MPU Registers

Joseph L. Lindo Data + and - Section 1 Assembly Programming Registers There are 8 general purpose registers, 6 segment registers, Eflags registers and instruction pointers. Registers

Joseph L. Lindo Data + and - Registers Assembly Programming Instruction Operand Types: Immediate – a constant integer (8, 16, or 32 bits) Register – the name of a register is converted to a number and encoded within the instruction Memory – reference to a location in memory Data

Joseph L. Lindo Data + and - Registers Assembly Programming Data Transfer Mnemonics Data

Joseph L. Lindo Data + and - Registers Assembly Programming Addition and Subtraction + and -

Joseph L. Lindo Assembly Programming --end-- Sir Joseph Lindo University of the Cordilleras

Joseph L. Lindo Assembly Programming --end na to-- Sir Joseph Lindo University of the Cordilleras

Joseph L. Lindo CPU vs MPU Online Task Provide the differences between CPU and MPU. Post it as comment on our FB Group. (COAL) Due on February 21, 2012

Joseph L. Lindo General Purpose Registers Registers Primarily used for arithmetic and data movement. Each register could be addressed as either 8, 16 or 32 bit value.

Joseph L. Lindo General Purpose Registers Registers

Joseph L. Lindo MOV Data Transfer Moves data fro source to destination Syntax: MOV destination,source Rules: Destination should not be an immediate operand

Joseph L. Lindo MOV Data Transfer.data count BYTE 100 wVal WORD 2.code mov bl,count mov al,wVal mov ax,wVal mov count,al mov ax,count mov eax,count

Joseph L. Lindo MOV Data Transfer CodeAXBX MOV ah,10 MOV ax,35 MOV bh,al MOV bx,1234 MOV bl,04 MOV bh,55

Joseph L. Lindo XCHG Data Transfer XCHG exchanges the values of two operands. Syntax: XCHG operand1,operand2 Rules: At least one operand must be a register. No immediate operands are permitted.

Joseph L. Lindo XCHG Data Transfer.data var1 WORD 1000h var2 WORD 2000h.code xchg ax,bx xchg ah,al xchg var1,bx xchg 3,100 xchg eax,ebx xchg var1,var2

Joseph L. Lindo XCHG Data Transfer CodeAXBX MOV bx,4810 MOV ax,35 XCHG bh,bl XCHG bh,ah MOV bl,04 XCHG bl,al

Joseph L. Lindo INC and DEC Add and Sub Add 1, subtract 1 from destination operand operand may be register or memory INC destination Logic: destination  destination + 1 DEC destination Logic: destination  destination – 1

Joseph L. Lindo INC and DEC Add and Sub.data myWord WORD 1000h myDword DWORD h.code inc myWord dec myWord inc myDword mov ax,00FFh inc ax mov ax,00FFh inc al

Joseph L. Lindo INC and DEC Add and Sub CodeAXBX MOV ah,10 MOV al,35 INC al MOV bx,1234 DEC bl INC bh

Joseph L. Lindo ADD and SUB Add and Sub ADD destination, source Logic: destination  destination + source SUB destination, source Logic: destination  destination – source Same operand rules as for the MOV instruction

Joseph L. Lindo ADD and SUB Add and Sub.data var1 DWORD 10000h var2 DWORD 20000h.code mov eax,var1 add eax,var2 add var2,var1 add ax,0FFFFh sub 1,2 sub var1,var2 add eax,1 sub ax,1

Joseph L. Lindo ADD and SUB Add and Sub CodeAXBX MOV ah,10 MOV al,35 ADD ah,al MOV bx,1294 SUB bl,ah ADD ax,bh

Joseph L. Lindo MOV and XCHG Comprehension Check

Joseph L. Lindo INC, DEC ADD and SUB Comprehension Check

Joseph L. Lindo Assembly Programming --end-- Sir Joseph Lindo University of the Cordilleras

Joseph L. Lindo Back Integer Expressions

Joseph L. Lindo INC and DEC MOV Reserved Word and Identifiers Directives Character and String Constants ADD and SUB More XCHG