assume cs:code
stack segment
db 128 dup (0)
stack ends
data segment
dw 0,0
data ends
code segment
start:mov ax,data
mov ds,ax
mov ax,stack
mov ss,ax
mov sp,128
mov ax,0
mov es,ax
mov ax,0b800h
mov es,ax
mov ah,'a'
show:mov es:[160*12+40*2],ah
call delay
inc ah
cmp ah,'z'
jna show
mov ax,0
mov es,ax
push ds:[0]
push es:[9*4]
push ds:[2]
pop es:[9*4+2]
mov ax,4c00h
int 21h
delay:push ax
push dx
mov dx,1000h
mov ax,0
m:sub ax,1 ;如果将此处换成dec ax，程序不可用,大家试。
sbb dx,0
cmp ax,0
jne m
cmp dx,0
jne m
pop dx
pop ax
ret
code ends
end start |
