请高手注释下这个汇编程序!

你应该把所用的器件，端口，说明一下，这应该是演奏音乐的程序，mus_freq负责需要的分频数，mus_time则是演奏时间

老大，写了要给分哦！！！！！重点啊

stack segment para stack 'stack' ；堆栈段

db 64 dup('stack...')

stack ends

*******************************************************************

dseg segment para 'data' ；数据段

mus_freq dw 262,294,330,262,262,294,330,262 频率

dw 330,349,392,330,349,392,392,440

dw 392,349,330,262,392,440,392,349

dw 330,262,294,196,262,294,196,262,-1

mus_time dw 25,25,25,25,25,25,25,25,25,25演奏时间

dw 50,25,25,50,12,12,12,12,25,25

dw 12,12,12,12,25,25,25,25,50,25,25,50

dseg ends

*******************************************************************

cseg segment para 'code'代码段

assume cs:cseg,ss:stack,ds:dseg；关联

-------------------------------------------------------------------

music proc far；远过程

mov ax,dseg

mov ds,ax将数据段基址非DS

lea si,mus_freq；将mus_freg的偏移地址非si

lea bp,ds:mus_time；将mus_time的偏移地址给bp

freq:

mov di,[si] ；读取数据段mus_freq的第一个值给di

cmp di,-1 ；是否为-1

je end_mus；为1则结束

mov bx,ds:[bp]；不相等则将数据段mus_time的第一个值给bx

call soundf；调用soundf

add si,2 ；si加一

add bp,2；bp加一

jmp freq ；循环啦

end_mus: ；退出exit

mov ax,4c00h

int 21h

music endp

******************************************************

soundf proc near

push ax

push bx；压栈保存ax，bx，cx，dx。di

push cx

push dx

push di

mov al,0b6h ；写控制字

out 43h,al ；43h应该为控制字端口

mov dx,12h

mov ax,348ch ；这应该是原始时钟

div di ；除mus_freq的值得到输出频率

out 42h,al ；将获得频率分两次给42h端口

mov al,ah

out 42h,al

in al,61h ；读取61h状态

mov ah,al 给ah

or al,3 将其与3相加

out 61h,al ；在将其输出到61h端口

wait1:

mov cx,6630 ；延时吧？cx控制延时长度

call waitf

dec bx ，bx为演奏的时间吧

jnz wait1 演奏完了，下一个

mov al,ah

out 61h,al

pop di

pop dx

pop cx

pop bx

pop ax

ret

soundf endp

******************************************************

waitf proc near

push ax

waitf1:

in al,61h 读取61h状态

and al,10h与10h与

cmp al,ahal是否和ah相等

je waitf1相等则继续等待

mov ah,al 不相等则将al给ah

loop waitf1 cx减一，循环

pop ax

ret返回

waitf endp

******************************************************

cseg ends

******************************************************

end music

令 T1 定时，到时，对输出端，取反即可。

ORG 0000H

JMP START

ORG 001BH

CPL P1.7

JNB F0, F2

MOV TH1, #0FEH

MOV TL1, #34H

RETI

F2:

MOV TH1, #0FEH

MOV TL1, #98H

RETI

START:

MOV TMOD, #10H

SETB TR1

MOV IE, #88H

LOOP:

MOV R5, #5

DJNZ R7, $

DJNZ R6, $ - 2

DJNZ R5, $ - 4

CPL F0

SJMP LOOP

END

---