单片机编音乐程序

6＝440Hz,#6＝440*1.059463＝466.2Hz,7＝440*1.059463*1.059463＝493.9Hz 
#5＝440÷1.059463＝415.3Hz
5＝440÷1.059463÷1.059463＝392Hz
相邻半音阶的关系为1.059463倍,只要知道"A"＝440Hz,即可算出其余半音阶的频率,比A高的用"*",比A低的用"÷"
1.059463＝12√2(即2开12次根)
440Hz为钢琴中央C组的A(即"6"音)
ok
这是本人一个产品中的音乐单元,很完整,供爱好者参考. 

       ORG     0000H
        AJMP    CSH             主程序进入点
        ORG     000BH
        LJMP    TIM0            定时中断T0入口
;
;**********
;* 初始化 *
;**********
;
        ORG     0020H
CSH:    MOV     R0,#7FH         内部RAM(00H～7FH)清零
CSH1:   MOV     @R0,#00H
        DJNZ    R0,CSH1
    MOV     SP,#60H         堆栈60H～7FH,【使用89C51】
        MOV     TMOD,#01H       TMOD=11H,T0作16位计数器(4M晶振)
        CLR     TCON.4          T0禁止动作
        SETB    IE.1            T0允许中断
        SETB    PT0             T0中断优先
        SETB    IE.7            系统允许中断
;
;**********
;* 主程序 *
;**********
;
MAIN:   MOV     5CH,#00         取简码谱指针
        LCALL   MUSIC
    MOV     5CH,#49         取简码谱指针
        LCALL   MUSIC
    MOV     5CH,#66         取简码谱指针
        LCALL   MUSIC
    MOV     5CH,#100        取简码谱指针
        LCALL   MUSIC
    MOV     5CH,#108        取简码谱指针
        LCALL   MUSIC
    MOV     5CH,#136        取简码谱指针
        LCALL   MUSIC
    MOV     5CH,#174        取简码谱指针
        LCALL   MUSIC
        AJMP    MAIN
;
;*************************
;* 音乐子程序 MUSIC      *
;* 入口: 5CH←简码谱指针 *
;*************************
;
MUSIC:  MOV     A,5CH           简码谱指针装入A
        MOV     DPTR,#TABLE     至TABLE取简码
        MOVC    A,@A+DPTR
        MOV     R2,A            取到的简码暂存于R2
        JZ      END1            是否取到00(结束码)?
        ANL     A,#0FH          不是,则取低四位(节拍码)
        MOV     R6,A            将节拍码存入R6
        MOV     A,R2            将取到的简码再装入R2
        SWAP    A               高低四位交换
        ANL     A,#0FH          取低四位(音符码)
        JNZ     SING            取到的音符码是否为0?
        CLR     TR0             是,则不发音
        AJMP    D1              跳到D1
;
SING:   DEC     A               取到的音符码减1
        MOV     4BH,A           存入(4BH)
        RL      A               乘2
        MOV     DPTR,#TABLE1    至TABLE1取相对的高字节计数值
        MOVC    A,@A+DPTR
        MOV     TH0,A           取到的高字节存入TH0
        MOV     4AH,A           取到的高字节存入(4AH)
        MOV     A,4BH           再装入取到的音符码
        RL      A               乘2
        INC     A               加1
        MOVC    A,@A+DPTR       至TABLE1取相对的低位
        MOV     TL0,A           取到的低字节存入TL0
        MOV     49H,A           取到的低字节存入(49H)
        SETB    TR0             启动TIMER0
D1:     CALL    DELAY           基本单位时间1/4拍187毫秒
        INC     5CH             取简码谱指针加1
        AJMP    MUSIC           取下一个码
DD1:    RET
;
STOP:   NOP
;    JB      P3.7,STOP1    在软件延时中掺插做其他动作
;       SETB    P2.7            P2.7←"1"
        NOP
        NOP
STOP0:  NOP
        RET
STOP1:  NOP
;    JB      P3.6,STOP0    在软件延时中掺插做其他动作
;       SETB    P2.6            P2.6←"1"
        RET
;
END1:   CLR     TR0             停止TIMER0
        RET
;
TIM0:   PUSH    A               将A的值暂存于堆栈区
        PUSH    PSW             将PSW的值暂存于堆栈区
        MOV     TL0,49H         重设计数值
        MOV     TH0,4AH
        CPL     P1.7            将输出端P1.1取反(P1.7接至无源蜂鸣器)
        POP     PSW             至堆栈区取回PSW的值
        POP     A               至堆栈区取回A的值
        RETI                    返回主程序
;
DELAY:  MOV     R7,#02          187毫秒
D2:     MOV     R4,#24
D3:     MOV     R3,#48
        DJNZ    R3,$
        ACALL   STOP        在软件延时中掺插做其他动作
        DJNZ    R4,D3
        DJNZ    R7,D2
        DJNZ    R6,DELAY        决定节拍
        RET
;                 .5   .6     .7    1
TABLE1: DW      65111,65150,65199,65217   4M晶振时的定时中断时间常数
;                  2    3     4     5     若采用其它频率,则要根据乐音的
        DW      65252,65283,65297,65323   频率计算,例中央C的A音为440Hz,
;                  6    7     1`    2`    440Hz＝2.273ms,把T0设置为2.273ms
        DW      65347,65367,65377,65394   中断即可发出A音.
;                 3`    4`    #6
        DW      65410,65417,65357
;
;***************************************************************
;* 音符代码  1  2  3  4  5  6  7  8  9  A  B  C  D  E  F   0   *
;* 音高     .5 .6 .7  1  2  3  4  5  6  7  1` 2` 3` 4` 5` 休止 *
;*-------------------------------------------------------------*
;* 节拍代码  1   2   3  4   5      6    8   A    C   F         *
;* 节拍     1/4 2/4 3/4 1 1(1/4) 1(1/2) 2 2(1/2) 3 3(3/4)      *
;*-------------------------------------------------------------*
;* 结束代码 00H                                                *
;*-------------------------------------------------------------*
;* 乐谱格式  每字节的高字节为音符代码,低字节为节拍代码         *  
;*-------------------------------------------------------------* 
;* 例子:        ⑴  ⑵  ⑶  ⑷  ⑸  ⑹  ⑺  ⑻  ⑼  ⑽  ⑾     *
;*      DB      A4H,02H,84H,02H,A4H,02H,84H,02H,D8H,04H,00H    *
;*      ⑴ A→唱"7" , 4→ 1 拍                                 *
;*      ⑵ 0→休止  , 2→2/4拍                                 * 
;*      ⑶ 8→唱"5" , 4→ 1 拍                                 * 
;*      ⑷ 0→休止  , 2→2/4拍                                 * 
;*      ⑸ A→唱"7" , 4→ 1 拍                                 *
;*      ⑹ 0→休止  , 2→2/4拍                                 *
;*      ⑺ 8→唱"5" , 4→ 1 拍                                 * 
;*      ⑻ 0→休止  , 2→2/4拍                                 *
;*      ⑼ D→唱"3`", 8→ 2 拍                                 *
;*      ⑽ 0→休止  , 4→ 1 拍                                 *
;*      ⑾ 00H→乐曲结束                                       *
;***************************************************************  
;
TABLE:
;【00】 
        DB      98H,02H,B4H,01H,94H,01H,68H,02H,94H,01H
        DB      64H,01H,48H,02H,64H,01H,44H,01H,28H,02H
        DB      64H,01H,94H,01H,B4H,01H,94H,01H,B4H,01H
        DB      94H,01H,B4H,01H,D4H,01H,94H,01H,64H,01H
        DB      44H,01H,64H,01H,98H,02H,01H,01H,00H
;【49】 
        DB      A4H,02H,84H,02H,A4H,02H,84H,02H,D8H,04H
        DB      C8H,01H,01H,01H,01H,01H,00H
;【66】 
        DB      42H,52H,62H,72H,82H,92H,A2H,B2H,42H,52H
        DB      62H,72H,82H,92H,A2H,B2H,00H
;【100】
        DB      61H,81H,B1H,D1H,B1H,81H,61H,00H
;【108】
        DB      11H,41H,61H,81H,61H,41H,11H,00H
;【136】
        DB      24H,04H,34H,04H,44H,04H,54H,04H,64H,04H,44H,04H,64H,04H,94H,04H
        DB      83H,01H,93H,01H,83H,01H,63H,01H,46H,02H,66H,02H
        DB      91H,21H,91H,21H,91H,21H,91H,21H,94H,00H
;【174】
        DB      94H,04H,A4H,04H,B4H,04H,C4H,04H,D4H,04H
        DB      B4H,04H,D8H,08H,C4H,04H,F4H,04H,CCH,00H
;
    END