为什么不一样呢~？

wth1150 2003-04-04 01:35:32

cseg segment
assume cs:cseg

start: MOV AX,1000h
MOV DS,AX
MOV SI,2345h
MOV AX,2000h
MOV es,AX
MOV di,3456h
MOV CX,0400h
next: MOV AL,ds:[SI]
MOV es:[di],al
INC SI
INC di
LOOP next
INT 3
mov ah,4ch
int 21
cseg ends
end start

第1段：
-u 1000:2345
1000:2345 0000 ADD [BX+SI],AL
1000:2347 0000 ADD [BX+SI],AL
1000:2349 0000 ADD [BX+SI],AL
1000:234B 0000 ADD [BX+SI],AL
1000:234D 0000 ADD [BX+SI],AL
1000:234F 0000 ADD [BX+SI],AL
1000:2351 00FF ADD BH,BH
1000:2353 7801 JS 2356
1000:2355 100A ADC [BP+SI],CL
1000:2357 0000 ADD [BX+SI],AL
1000:2359 8700 XCHG AX,[BX+SI]
1000:235B 820065 ADD BYTE PTR [BX+SI],65
1000:235E 0470 ADD AL,70
1000:2360 006504 ADD [DI+04],AH
1000:2363 7000 JO 2365

第2段（执行程序后）
-u 2000:3456
2000:3456 0000 ADD [BX+SI],AL
2000:3458 0000 ADD [BX+SI],AL
2000:345A 0000 ADD [BX+SI],AL
2000:345C 0000 ADD [BX+SI],AL
2000:345E 0000 ADD [BX+SI],AL
2000:3460 0000 ADD [BX+SI],AL
2000:3462 00FF ADD BH,BH
2000:3464 7801 JS 3467
2000:3466 100A ADC [BP+SI],CL
2000:3468 0000 ADD [BX+SI],AL
2000:346A 8700 XCHG AX,[BX+SI]
2000:346C 820065 ADD BYTE PTR [BX+SI],65
2000:346F 0470 ADD AL,70
2000:3471 006504 ADD [DI+04],AH
2000:3474 7000 JO 3476

有人能帮我解释下吗？

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