9sjb.asm

几个接口实验的代码。内含：8253、8255、8237、8251、DA0832、AD0809等芯片的实验代码！

code segment
   assume cs:code,ds:code
start:
    mov ax,code
    mov ds,ax
s1:
    mov cx,0ffh

    mov al,0FFH
s2: mov dx,228h  
    out dx,al
    mov dx,229h
    out dx,al
    dec al
    cmp al,0ffh
    jnz s2

    mov al,00h
s3: mov dx,228h
    out dx,al
    mov dx,229h
    out dx,al
    inc al
    cmp al,0ffh
    jnz s3

    jmp s2

code     ends
   end     start