汇编语言习题及答案 (3)

MOV CX, I ADD CX,1 MOVE: CLD LODSB STD STOSB LOOP MOVE 4、解： DATA SEGMENT

ARR DW a1, a2, a3, a4, a5, a6, SUM DW ? DATA ENDS CODE SEGMENT

ASSUME DS: DATA, CS: CODE START:

MOV AX, DATA MOV DS, AX LEA BX, ARR MOV CX, 100 MOV AX, 0 AGAIN:

?, a100 ADD AX, [BX] ADD BX, 2 LOOP AGAIN MOV AX, 4C00H INT 21H CODE ENDS END START 5、解：

BEGIN: MOV AH, 01H INT 21H CMP AL,’a’ JB FIN CMP AL,’z’ JA FIN SUB AL, 20H MOV DL, AL MOV AH, 02H INT 21H JMP BEGIN FIN: RET 6、解：

DATA SEGMENT

STRING1 DB ‘HERE YOU ARE’ STRING2 DB ‘HERE YOU AER’ YES DB ‘MATCH’, 0DH, 0AH, ’$’ NO DB ‘NO MATCH’, 0DH, 0AH, ‘$’ DATA ENDS CODE SEGEMTN

ASSUME CS:CODE, DS: DTAT START:

MOV AX, DATA MOV DS, AX BEGIN:

LEA AL, STRING1 LEA DL, STRING2

MOX CX, STRING2 – STRING1 REP CMPSB JNE DISPNO MOV AH, 09H LEA DX, YES INT 21H JMP EXIT DISPNO: MOV AH, 09H

LEA DX, NO INT 21H EXIT:

MOV AX, 4C00H INT 21H CODE ENDS END START

阅读下列各指令序列段，写出它们各完成什么功能1．

SUB AX, CX

SBB DX, BX 2．

PUSH AX

PUSH BX POP AX POP BX

3．

假设DS，ES初始化到同一数据段 CLD MOV CX, 20 LEA SI, STRING1 LEA DI, STRING2 REP MOVSB 4．

CLD

MOV CX,COUNT

MOV AL, ‘ ‘ ;空格 LEA DI, CHAR_FIELD REP STOSB