zhuan.asm

有关芯片8253/8255/8259的程序

code segment
assume cs:code
start:mov ah,1
      int 21h
      cmp al,7ah
      jg end1
      cmp al,61h
      jb big
      and al,0dfh
      mov dl,al
      mov ah,2
      int 21h
      jmp start
 big:cmp al,5ah
     jg end1
     cmp al,41h
     jb end1
     or al,20h
     mov dl,al
     mov ah,2
     int 21h
     jmp start
 end1:mov ah,4ch
      int 21h
code ends
end start