3.3.1

.ASM .OBJ .EXE

SEGMENT ENDS

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CPUCPU

[] [] [][] [ ]

[] [] [ ]

,31,,(,,)

CPU

,,

AABCDASCII41H42H43H44H

+-*/MOD ANDORNOTXORMOV AL8 AND 4 MOV AL8+4-1

0FFFFHEQNELTGTLEGE

OFFSET SEG TYPE LENGTH SIZE

MOV AXSEG DATA MOV DSAX MOV BXOFFSET DATA LEA BXDATA

BUFFER BUFFER DW 200 DUP(0) TYPE BUFFER 2 LENGTH BUFFER200 SIZE BUFFER400

PTR MOV BYTE PTR[BX]12H

[ ]

[ ]

3.3.2

DB DW DD 4DQ 48DT 10

DATA1 DB 11H22H33H44HDATA2 DW 11H22H3344HDATA3 DD 11H*222H33445566H

DB DATA1 DB ABCD66HABCD41H42H43H44H66H

[] n DUP DW 20 DUP0 DB 3 DUP22H11H

MEM1 DB 34HA DW 20 DUP40

EQU CONSTANTEQU100 VAR EQU 30H+99HEQU

SEGMENT [] [] []

ENDS

PARA 16 1BYTE WORDPAGE 256 1

NONE PUBLIC LINKCOMMON STACK AT MEMORY

DATA SEGMENTMEM1 DB 11H22HDATA ENDS

ASSUME []

END []

DSEG SEGMENTDATA1 DB 12DATA2 DW 1234HDSEG ENDSESEG SEGMENT DB 20 DUPESEG ENDSSSEG SEGMENT STACK STACK Dw 200 DUPSSEG ENDS

CSEG SEGMENT ASSUME CSCSEGDSDSEG ESESEGSSSSEG STARTMOV AXDSEG MOV DSAX MOV AXESEG MOV ESAX MOV AXSSEG MOV SSAX CSEG ENDS END START

PROC [ NEAR / FAR ] RET ENDPP166

-------- MACRO ENDMP167

ORG ------- ORG ORG 2000H

NAME------- NAME

TITLE------- TITLE P169

4.3 DOS BIOS

DOS 21HC

DOS

DOS MOV AH INT 21H

1. MOV AH01 INT 21HAL

GET_KEY: MOVAH,1 INT21H CMPAL,Y JZ YES CMPAL,N JZ NO JNZGET_KEY YES: jmp exit NO: exit

2. AH OAHDSDX INT 21H

0DHN1N2

DAT1 DB 2020 DUP

LEA DXDAT1 MOV AH0AH INT 21H

14H 20

3. AH O2HDL INT 21H

MOVAH02 MOVDL41H INT21HA

4. AH O9HDSDX INT 21H

$,ASCII

DATA SEGMENTMESS1 DB Input String: 0DH0AH,$DATA ENDSCODE SEGMENT MOVAH09MOVDXOFFSET MESS1INT21H

4.4

D:\masm>EDIT D:\masm>MASM D:\masm>LINK D:\masm>TD