1.顯示字元串:
代碼:
assume cs:code
data segment
db 'welcome to masm!',0
data ends
code segment
start: mov dh,8
mov dl,3
mov cl,2
mov ax,data
mov ds,ax
mov si,0
call show_str
mov ax,4c00h
int 21h
show_str: push dx
push cx
push si
mov di,0
mov bl,dh
dec bl
mov al,160
mul bl
mov bx,ax
add dl,dl
add bl,dl
mov ax,0b800h
mov es,ax
mov al,cl
s: mov ch,0
mov cl,ds:[si]
jcxz ok
mov es:[bx+di],cl
mov es:[bx+di+1],al
add di,2
inc si
loop s
ok: pop dx
pop cx
pop si
ret
code ends
end start
2.解決除法溢出問題:
代碼:
assume cs:code,ss:stack
stack segment
dw 8 dup (0)
stack ends
code segment
start: mov ax,stack
mov ss,ax
mov sp,16
mov ax,4240h
mov dx,00fh
mov cx,0ah
call divdw
mov ax,4c00h
int 21h
divdw: push ax
mov ax,dx
mov dx,0
div cx
mov bx,ax
pop ax
div cx
mov cx,dx
mov dx,bx
ret
code ends
end start
3.數值顯示:
代碼:
assume cs:code
data segment
db 10 dup (0)
data ends
stack segment
dw 8 dup(0)
stack ends
code segment
start: mov ax,42243
mov bx,data
mov ds,bx
mov bx,stack
mov ss,bx
mov sp,10h
mov si,0
call dtoc
mov dh,8
mov dl,3
mov cl,2
call show_str
mov ax,4c00h
int 21h
dtoc: push ax
push bx
push si
mov bx,10
mov si,0
s0: mov dx,0
div bx
add dx,30h
push dx
mov cx,ax
inc si
inc cx
loop s0
mov cx,si
mov si,0
s1: pop ds:[si]
inc si
loop s1
pop si
pop bx
pop ax
ret
show_str: push ax
push dx
push cx
push si
mov di,0
mov bl,dh
dec bl
mov al,160
mul bl
mov bx,ax
add dl,dl
add bl,dl
mov ax,0b800h
mov es,ax
mov al,cl
s: mov ch,0
mov cl,ds:[si]
jcxz ok
mov es:[bx+di],cl
mov es:[bx+di+1],al
add di,2
inc si
loop s
ok: pop si
pop cx
pop dx
pop ax
ret
code ends
end start