assume cs:code
code segment
start: mov al, 06dh
call showbyte
mov ax, 4c00h
int 21h
showbyte: jmp short show
table db '0123456789ABCDEF'
show: push bx
push es
mov ah, al
shr ah, 1
shr ah, 1
shr ah, 1
shr ah, 1
and al, 00001111b
mov bl, ah
mov bh, 0
mov ah, table[bx]
mov bx, 0b800h
mov es, bx
mov es:[160*12+40*2], ah
mov bl, al
mov bh, 0
mov al, table[bx]
mov es:[160*12+40*2+2], al
pop es
pop bx
ret
code ends
end start
我在cmd和command下都不能显示,最后在dos实模式下才显示,是代码写错了吗?还是其他原因? |