Assembly Language Homework Project (Two)

Assembly Language Homework Project (Two)

键盘输入两个十进制非符号数(≤65535)，计算两数之乘积，分别以十进制、十六进制、二进制输出结果。例如：

输入：
12345
65535

输出：

12345*65535=

809029575

3038CFC7h

0011 0000 0011 1000 1100 1111 1100 0111B

.386data segment use16  buf db 7, 0, 7 dup(0);input the number  s   db 20 dup(0);output the formula  p   db 40 dup(" "), 0Dh, 0Ah, '$';output the decimal result   m   db 40 dup(" "), 0Dh, 0Ah, '$';output the hexadecimal result  n   db 40 dup(" "), 0Dh, 0Ah, '$';output the binary resultdata endscode segment use16assume cs:code, ds:datamain:   mov ax, data   mov ds, ax   mov si, 0   call input   call convert   push ax   call newline   mov s[si],'*'   inc si   call input      call convert   mov s[si], '='   inc si   mov s[si], '$'   mov dx, 0   mov bx, ax   pop ax   mul bx;ax is multipled by bx         ;the result:dx:ax = high 16 digits : low 16 digits   call output   call outputdec   call outputH   call outputB   mov ah, 4Ch   int 21h;------Convert------------------------------;Goal: To convert strings to numbers;Way : Use the multiplication;Parameter: buf, sconvert:   mov bx, 2   mov ax, 0   mov dx, 0  next:   mov dl, buf[bx]   cmp dl, 0Dh   je done   imul ax, ax, 10   mov s[si], dl   sub dl, '0'   add ax, dx   inc bx   inc si   jmp next  done:   ret;------End of Convert----------------------;------Output------------------------------output:   push ax   push dx   mov ax, 0   mov dx, 0   call newline   mov dx, offset s   mov ah, 09h   int 21h   pop dx   pop ax   ret;------End of Output-----------------------;------Outputdec---------------------------;Goal: To output the decimal result;Way : Use the division;Example:  123 -> 123%10 -> 3;          12  -> 12%10  -> 2    ;          1   -> 1%10   -> 1 ;          stack: 123outputdec:   push ax   push dx   mov ah, 2   mov dl, 0Dh   int 21h   mov ah, 2   mov dl, 0Ah   int 21h   pop dx   pop ax   push ax   push dx   xor cx, cx   xor di, diagain:   push cx   mov cx, 10   call divdw   pop cx   add dl, '0'   push dx   mov dx, bx   inc cx   cmp ax, 0   jne againpop_again:   pop dx   mov p[di], dl   inc di   dec cx   jnz pop_again   mov ah, 09h   mov dx, offset p   int 21h   pop dx   pop ax   ret;------End of Outputdec--------------------;------OutputH-----------------------------;Goal: To output the hexademical result;Way : Use the shift;Example: 7FFFh -> FFF7h And 000Fh -> 7;         FFF7h -> FF7Fh And 000Fh -> F;         FF7Fh -> F7FFh And 000Fh -> F;         F7FFh -> 7FFFh And 000Fh -> F;         result: 7FFFhoutputH:   push ax   push dx   push ax   mov ax, dx   mov cx, 4   mov bx, 2   mov di, 0again1:   push cx   mov cl, 4   rol ax, cl   push ax   and ax, 000Fh   cmp ax, 10   jb is_digitis_alpha:   sub al, 10   add al, 'A'   jmp finish_4bitsis_digit:   add al,'0'finish_4bits:   mov n[di], al   pop ax   pop cx   inc di   dec cx   jnz again1   dec bx   cmp bx, 0   je next1   mov cx, 4   pop ax   jmp again1next1:   mov n[di],'h'   mov ah, 9   mov dx, offset n   int 21h   pop dx   pop ax   ret;------End of OutputH------------------;------OutputB-------------------------;Goal: To output the binary result;Way : Use the shfit;Example: 1011B -> 0111B And 0001h -> 1;         0111B -> 1110B And 0001h -> 0;         1110B -> 1101B And 0001h -> 1;         1101B -> 1011B And 0001h -> 1;         result: 1101BoutputB:   push ax   mov ax, dx   mov cx, 10h   mov di, 0   mov bx, 2   mov si, 4again2:   push cx   mov cl, 1   rol ax, cl   push ax   and ax, 0001h   add al, '0'   mov m[di], al   pop ax   pop cx   inc di   dec si   cmp si, 0   jne continue   inc di   mov si, 4 continue:   dec cx     jnz again2   dec bx   cmp bx, 0   je next2   mov cx, 10h   pop ax   jmp again2next2:   dec di   mov m[di], 'B'   mov ah, 9   mov dx, offset m   int 21h   ret;------End of OutputB------------------;------Divdw---------------------------;Goal: To solve the problem---overflow;Way : Use the formula;      X/N=int(H/N)*65535+[rem(H/N)*65535+L]/N;Parameter :dividend: dx:ax = high 16 digits : low 16 digits;           divisor : cx;;Return    :quotient : bx = high 16 digits ax =  low 16 digits;          :remainder: dxdivdw:   push ax   mov ax, dx   xor dx, dx   div cx   mov bx, ax   pop ax   div cx   ret;------End of Divdw--------------------;------Newline-------------------------;Use int 21h ah=02h;Output '\n'newline:   mov ah, 02h   mov dl, 0Dh   int 21h   mov ah, 02h   mov dl, 0Ah   int 21h   ret;------End of Newline-------------------;------Input---------------------------- input:   mov ah, 0Ah   mov dx, offset buf   int 21h   ret;------End of Input---------------------code endsend main

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