汇编语言——1~7音阶

; 1~7音阶
assume cs:codeseg
data segment
       dw 262,294,330,349,392,440,494,524        ;1~7频率
data ends
codeseg segment
start: 
       mov ax, data
       mov ds, ax
       mov si, 0
       mov bl, 8
play:
       mov al,0b6h          ;8253芯片初始化
       out 43h,al           ;43H是8253芯片控制口的端口地址
       mov dx,12h
       mov ax,34dch
       div word ptr [si]    ;设置声音的频率
       out 42h, al
       mov al, ah
       out 42h, al

       in al, 61h           ;读设备控制器端口原值
       mov ah, al           ;保存原值
       or al, 3             ;打开扬声器和定时器
       out 61h, al          ;接通扬声器，发声

       mov dx, 10           ;延时
delay0:
       mov cx, 60000
delay1:
       nop
       loop delay1
       dec dx
       jne delay0

       mov al, ah           ;恢复端口原值
       out 61h, al

       add si, 2
       dec bl
       jne play

       mov ax, 4c00h
       int 21h
codeseg ends
end start