assembly/DIVISION.ASM at main · mavyfaby/assembly · GitHub

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
jmp start

    dvs     db      0
    dvn     db      0
    quo     db      0
    rmd     db      0

    ms1     db      'Enter dividend: $'
    ms2     db      'Enter divisor: $'
    ms3     db      'Answer: $'
    clf     db      13,10,'$'

start:

    ; clear registers
    call clear_r
    call clear_v

    ; print message
    lea dx,ms1
    mov ah,9
    int 21h

    ; accept dividend
    mov ah,1
    int 21h

    ; store dividend to dvn
    sub al,30h
    mov dvn,al

    ; print line
    call n_line

    ; clear registers
    call clear_r

    ; print message
    lea dx,ms2
    mov ah,9
    int 21h

    ; accept divisor
    mov ah,1
    int 21h

    ; store divisor to dvs
    sub al,30h
    mov dvs,al

    ; print line
    call n_line
    call n_line

    ; clear registers
    call clear_r

    ; perform division
    mov al,dvn
    mov bl,dvs
    div bl

    ; store quotient and remainder
    or al,30h
    mov quo,al

    or ah,30h
    mov rmd,ah

    ; print result message
    lea dx,ms3
    mov ah,9
    int 21h

    ; print quotient
    mov dl,quo
    mov ah,2
    int 21h

    ; print dot
    mov dl,'.'
    mov ah,2
    int 21h

    ; set loop counter
    mov cx,5

    ; perform division
    call pf_div

    ; stop program
    int 20h

pf_div:

    ; clear registers except cx
    xor ax,ax
    xor bx,bx
    xor dx,dx

    ; multiply remainder by 10
    sub rmd,30h
    mov al,rmd
    mov bl,10
    mul bl

    ; divide it by the divisor
    mov bl,dvs
    div bl

    ; store remainder to rmd
    or ah,30h
    mov rmd,ah

    ; print qoutient
    or al,30h
    mov dl,al
    mov ah,2
    int 21h

    ; loop until cx is 0
    loop pf_div

    ret

n_line:
    lea dx,clf
    mov ah,9
    int 21h
    ret

clear_r:
    xor ax,ax
    xor bx,bx
    xor cx,cx
    xor dx,dx
    ret

clear_v:
    mov ax,3
    int 10h
    ret