hx.asm

微机原理——接口应用编程源码

stack segment stack
dw 64 dup(?)
stack ends
data segment
table db 4dh
data ends
code segment
 assume cs:code,ds:data
start: mov ax,data
       mov ds,ax
       push ds
       mov ax,0000h
       mov ds,ax
       mov ax,offset irq7
       add ax,2000h
a2:    mov si,003ch
       mov [si],ax
       mov ax,0000h
       mov si,003eh
       mov [si],ax
       
       mov al,13h
       out 20h,al
       mov al,08h
       out 21h,al
       mov al,09h
       out 21h,al
       mov al,7fh
       out 21h,al
       sti
       mov dx,43h
       mov al,10010001b
       out dx,al
       mov dx,42h
       mov al,05h
       out dx,al

   a1: jmp a1
irq7:   mov ax,014dh
        int 10h
        mov al,20h
        out 20h,al
       jmp a2
 iret
 code ends
 end start