- 实验任务1
1 assume cs:code, ds:data 2 3 data segment 4 x dw 1020h, 2240h, 9522h, 5060h, 3359h, 6652h, 2530h, 7031h 5 y dw 3210h, 5510h, 6066h, 5121h, 8801h, 6210h, 7119h, 3912h 6 data ends 7 code segment 8 start: 9 mov ax, data 10 mov ds, ax 11 mov si, offset x 12 mov di, offset y 13 call add128 14 15 mov ah, 4ch 16 int 21h 17 18 add128: 19 push ax 20 push cx 21 push si 22 push di 23 24 sub ax, ax 25 26 mov cx, 8 27 s: mov ax, [si] 28 adc ax, [di] 29 mov [si], ax 30 31 inc si 32 inc si 33 inc di 34 inc di 35 loop s 36 37 pop di 38 pop si 39 pop cx 40 pop ax 41 ret 42 code ends 43 end start
- line31~line34的4条inc指令，能否替换成如下代码？你的结论的依据/理由是什么？
不能替换，因为add命令可能会改变标志位CF
- 在debug中调试，观察数据段中做128位加之前和加之后，数据段的值的变化。给出调试观察截图
- 实验任务2
1 assume cs:code, ds:data 2 data segment 3 str db 80 dup(?) 4 data ends 5 6 code segment 7 start: 8 mov ax, data 9 mov ds, ax 10 mov si, 0 11 s1: 12 mov ah, 1 13 int 21h 14 mov [si], al 15 cmp al, '#' 16 je next 17 inc si 18 jmp s1 19 next: 20 mov ah, 2 21 mov dl, 0ah 22 int 21h 23 24 mov cx, si 25 mov si, 0 26 s2: mov ah, 2 27 mov dl, [si] 28 int 21h 29 inc si 30 loop s2 31 32 mov ah, 4ch 33 int 21h 34 code ends 35 end start
① 汇编指令代码line11-18，实现的功能是？
从输入里读入一串字符，直到#时候停止。
② 汇编指令代码line20-22，实现的功能是？
输出换行符。
③ 汇编指令代码line24-30，实现的功能是？
打印刚刚输入的字符。
- 实验任务3
1 assume cs:code,ds:data 2 3 data segment 4 x dw 91, 792, 8536, 65521, 2021 5 len equ $ - x 6 data ends 7 8 code segment 9 start: 10 mov ax, data 11 mov ds, ax 12 mov si, offset x 13 14 mov cx, len/2 15 s: mov ax, [si] 16 call printNumber 17 call printSpace 18 inc si 19 inc si 20 loop s 21 mov ax, 4c00h 22 int 21h 23 24 printNumber: 25 push cx 26 mov cx, 0 27 28 s1:mov dx, 0 29 mov bx, 10 30 div bx 31 push dx 32 inc cx 33 cmp ax, 0 34 jne s1 35 36 mov ah, 2 37 s2:pop dx 38 add dx, 48 39 int 21h 40 loop s2 41 42 pop cx 43 ret 44 45 printSpace: 46 mov ah, 2 47 mov dl, 20h 48 int 21h 49 ret 50 code ends 51 end start
- 实验任务4
1 assume cs:code,ds:data 2 data segment 3 str db "assembly language, it's not difficult but tedious" 4 len equ $ - str 5 data ends 6 7 stack segment 8 db 8 dup(?) 9 stack ends 10 11 code segment 12 start: 13 mov ax, data 14 mov ds, ax 15 mov si, 0 16 mov cx, len 17 call strupr 18 call printStr 19 20 mov ax, 4c00h 21 int 21h 22 23 strupr: 24 push cx 25 push si 26 s: 27 mov al, ds:[si] 28 cmp al, 97 29 jl c 30 cmp al, 122 31 jg c 32 and al, 0dfh 33 mov ds:[si], al 34 c: 35 inc si 36 loop s 37 38 pop si 39 pop cx 40 ret 41 42 43 printStr: 44 push cx 45 push si 46 s2: 47 mov ah, 2 48 mov dl, ds:[si] 49 int 21h 50 inc si 51 loop s2 52 53 pop si 54 pop cx 55 ret 56 57 code ends 58 end start
- 实验任务5
1 assume cs:code, ds:data 2 3 data segment 4 str1 db "yes", '$' 5 str2 db "no", '$' 6 data ends 7 8 code segment 9 start: 10 mov ax, data 11 mov ds, ax 12 13 mov ah, 1 14 int 21h 15 16 mov ah, 2 17 mov bh, 0 18 mov dh, 24 19 mov dl, 70 20 int 10h 21 22 cmp al, '7' 23 je s1 24 mov ah, 9 25 mov dx, offset str2 26 int 21h 27 28 jmp over 29 30 s1: mov ah, 9 31 mov dx, offset str1 32 int 21h 33 over: 34 mov ah, 4ch 35 int 21h 36 code ends 37 end start
【功能】判断输入的字符是不是7，如果结果为是，打印yes，否则就输出no。
- 实验任务6
1 assume cs:code 2 3 code segment 4 start: 5 int 42 6 7 mov ah, 4ch 8 int 21h 9 code ends 10 end start
1 assume cs:code 2 code segment 3 start: 4 ; 42 interrupt routine install code 5 mov ax, cs 6 mov ds, ax 7 mov si, offset int42 ; set ds:si 8 mov ax, 0 9 mov es, ax 10 mov di, 200h ; set es:di 11 mov cx, offset int42_end - offset int42 12 cld 13 rep movsb 14 ; set IVT(Interrupt Vector Table) 15 mov ax, 0 16 mov es, ax 17 mov word ptr es:[42*4], 200h 18 mov word ptr es:[42*4+2], 0 19 mov ah, 4ch 20 int 21h 21 int42: 22 jmp short int42_start 23 str db "welcome to 2049!" 24 len equ $ - str 25 ; display string "welcome to 2049!" 26 int42_start: 27 mov ax, cs 28 mov ds, ax 29 mov si, 202h 30 mov ax, 0b800h 31 mov es, ax 32 mov di, 24*160 + 32*2 33 mov cx, len 34 s: mov al, [si] 35 mov es:[di], al 36 mov byte ptr es:[di+1], 2 37 inc si 38 add di, 2 39 loop s 40 iret 41 int42_end: 42 nop 43 code ends 44 end start