单片机比如51系列都有定时器，因此可以利用它来控制扬声器按一定频率发声，以下就是一个例程，用按键的按下和抬起来模拟电子琴的控制程序。
T0H EQU 30H
T0L EQU 31H
ORG 0000H
LJMP MAIN
ORG 000BH
LJMP T0ISR
ORG 0030H
MAIN:
MOV SP,#5FH
MOV TMOD,#01H
SETB ET0
SETB EA
LOOP:
MOV DPTR,#FREQ
MOV A,P2 ;控制高中低音区
MOV R1,#0
ANL A,#03H
JB ACC.0,LOOP01
MOV R1,#14
SJMP LOOP0
LOOP01:
JB ACC.1,LOOP0
MOV R1,#28
LOOP0:
JB P0.0,LOOP1 ;控制音频1234567
MOV A,R1
MOVC A,@A+DPTR
MOV T0H,A
INC DPTR
MOV A,R1
MOVC A,@A+DPTR
MOV T0L,A
LJMP LOOP
LOOP1:
JB P0.1,LOOP2
MOV A,R1
ADD A,#2
MOVC A,@A+DPTR
MOV T0H,A
INC DPTR
MOV A,R1
ADD A,#2
MOVC A,@A+DPTR
MOV T0L,A
LJMP LOOP
LOOP2:
JB P0.2,LOOP3
MOV A,R1
ADD A,#4
MOVC A,@A+DPTR
MOV T0H,A
INC DPTR
MOV A,R1
ADD A,#4
MOVC A,@A+DPTR
MOV T0L,A
LJMP LOOP
LOOP3:
JB P0.3,LOOP4
MOV A,R1
ADD A,#6
MOVC A,@A+DPTR
MOV T0H,A
INC DPTR
MOV A,R1
ADD A,#6
MOVC A,@A+DPTR
MOV T0L,A
LJMP LOOP
LOOP4:
JB P0.4,LOOP5
MOV A,R1
ADD A,#8
MOVC A,@A+DPTR
MOV T0H,A
INC DPTR
MOV A,R1
ADD A,#8
MOVC A,@A+DPTR
MOV T0L,A
LJMP LOOP
LOOP5:
JB P0.5,LOOP6
MOV A,R1
ADD A,#10
MOVC A,@A+DPTR
MOV T0H,A
INC DPTR
MOV A,R1
ADD A,#10
MOVC A,@A+DPTR
MOV T0L,A
LJMP LOOP
LOOP6:
JB P0.6,LOOP7
MOV A,R1
ADD A,#12
MOVC A,@A+DPTR
MOV T0H,A
INC DPTR
MOV A,R1
ADD A,#12
MOVC A,@A+DPTR
MOV T0L,A
LJMP LOOP
LOOP7:
CLR TR0
LJMP LOOP
;-----------------------------
T0ISR:
CLR TR0
MOV TH0,T0H
MOV TL0,T0L
SETB TR0
CPL P3.0
RETI
;-----------------------------
FREQ:
DB 0F2H,03DH ;低音1
DB 0F3H,0BDH ;低音2
DB 0F5H,014H ;低音3
DB 0F5H,0B1H ;低音4
DB 0F6H,0D0H ;低音5
DB 0F7H,0D1H ;低音6
DB 0F8H,0B5H ;低音7
DB 0F9H,01EH ;中音1
DB 0F9H,0DEH ;中音2
DB 0FAH,08AH ;中音3
DB 0FAH,0D8H ;中音4
DB 0FBH,068H ;中音5
DB 0FBH,0E8H ;中音6
DB 0FCH,05AH ;中音7
DB 0FCH,08FH ;高音1
DB 0FCH,0EFH ;高音2
DB 0FDH,045H ;高音3
DB 0FDH,06CH ;高音4
DB 0FDH,0B4H ;高音5
DB 0FDH,0F4H ;高音6
DB 0FEH,029H ;高音7
;-----------------------------
END
unsigned char Count;
sbit fengming=P3^4 ; //单片机蜂鸣器定义
unsigned char code SONG[] ={ //祝你平安
0x26,0x20,0x20,0x20,0x20,0x20,0x26,0x10,0x20,0x10,0x20,0x80,0x26,0x20,0x30,0x20,
0x30,0x20,0x39,0x10,0x30,0x10,0x30,0x80,0x26,0x20,0x20,0x20,0x20,0x20,0x1c,0x20,
0x20,0x80,0x2b,0x20,0x26,0x20,0x20,0x20,0x2b,0x10,0x26,0x10,0x2b,0x80,0x26,0x20,
0x30,0x20,0x30,0x20,0x39,0x10,0x26,0x10,0x26,0x60,0x40,0x10,0x39,0x10,0x26,0x20,
0x30,0x20,0x30,0x20,0x39,0x10,0x26,0x10,0x26,0x80,0x26,0x20,0x2b,0x10,0x2b,0x10,
0x2b,0x20,0x30,0x10,0x39,0x10,0x26,0x10,0x2b,0x10,0x2b,0x20,0x2b,0x40,0x40,0x20,
0x20,0x10,0x20,0x10,0x2b,0x10,0x26,0x30,0x30,0x80,0x18,0x20,0x18,0x20,0x26,0x20,
0x20,0x20,0x20,0x40,0x26,0x20,0x2b,0x20,0x30,0x20,0x30,0x20,0x1c,0x20,0x20,0x20,
0x20,0x80,0x1c,0x20,0x1c,0x20,0x1c,0x20,0x30,0x20,0x30,0x60,0x39,0x10,0x30,0x10,
0x20,0x20,0x2b,0x10,0x26,0x10,0x2b,0x10,0x26,0x10,0x26,0x10,0x2b,0x10,0x2b,0x80,
0x18,0x20,0x18,0x20,0x26,0x20,0x20,0x20,0x20,0x60,0x26,0x10,0x2b,0x20,0x30,0x20,
0x30,0x20,0x1c,0x20,0x20,0x20,0x20,0x80,0x26,0x20,0x30,0x10,0x30,0x10,0x30,0x20,
0x39,0x20,0x26,0x10,0x2b,0x10,0x2b,0x20,0x2b,0x40,0x40,0x10,0x40,0x10,0x20,0x10,
0x20,0x10,0x2b,0x10,0x26,0x30,0x30,0x80,0x00,
//路边的野花不要采
0x30,0x1C,0x10,0x20,0x40,0x1C,0x10,0x18,0x10,0x20,0x10,0x1C,0x10,0x18,0x40,0x1C,
0x20,0x20,0x20,0x1C,0x20,0x18,0x20,0x20,0x80,0xFF,0x20,0x30,0x1C,0x10,0x18,0x20,
0x15,0x20,0x1C,0x20,0x20,0x20,0x26,0x40,0x20,0x20,0x2B,0x20,0x26,0x20,0x20,0x20,
0x30,0x80,0xFF,0x20,0x20,0x1C,0x10,0x18,0x10,0x20,0x20,0x26,0x20,0x2B,0x20,0x30,
0x20,0x2B,0x40,0x20,0x20,0x1C,0x10,0x18,0x10,0x20,0x20,0x26,0x20,0x2B,0x20,0x30,
0x20,0x2B,0x40,0x20,0x30,0x1C,0x10,0x18,0x20,0x15,0x20,0x1C,0x20,0x20,0x20,0x26,
0x40,0x20,0x20,0x2B,0x20,0x26,0x20,0x20,0x20,0x30,0x80,0x20,0x30,0x1C,0x10,0x20,
0x10,0x1C,0x10,0x20,0x20,0x26,0x20,0x2B,0x20,0x30,0x20,0x2B,0x40,0x20,0x15,0x1F,
0x05,0x20,0x10,0x1C,0x10,0x20,0x20,0x26,0x20,0x2B,0x20,0x30,0x20,0x2B,0x40,0x20,
0x30,0x1C,0x10,0x18,0x20,0x15,0x20,0x1C,0x20,0x20,0x20,0x26,0x40,0x20,0x20,0x2B,
0x20,0x26,0x20,0x20,0x20,0x30,0x30,0x20,0x30,0x1C,0x10,0x18,0x40,0x1C,0x20,0x20,
0x20,0x26,0x40,0x13,0x60,0x18,0x20,0x15,0x40,0x13,0x40,0x18,0x80,0x00,
};
void Time0_Init()
{
TMOD = 0x01;
IE = 0x82;
TH0 = 0xD8;
TL0 = 0xEF; //12MZ晶振，10ms
}
void Time0_Int() interrupt 1
{
TH0 = 0xD8;
TL0 = 0xEF;
Count++; //长度加1
}
/*-------------------------------------------------
功能:1MS延时子程序
-------------------------------------------------*/
void Delay_xMs(unsigned int x)
{
unsigned int i,j;
for( i =0;i < x;i++ )
{
for( j =0;j<3;j++ );
}
}
/*-------------------------------------------------
功能:歌曲播放子程序i为播放哪一段曲目
-------------------------------------------------*/
void Play_Song(unsigned char i)
{
unsigned char Temp1,Temp2;
unsigned int Addr;
Count = 0; //中断计数器清0
Addr = i * 217;
while(1)
{
Temp1 = SONG[Addr++];
if ( Temp1 == 0xFF ) //休止符
{
TR0 = 0;
Delay_xMs(100);
}
else if ( Temp1 == 0x00 ) //歌曲结束符
{
Addr++;
i++;
if(i==2)
{
i=0;
return;
}
}
else
{
Temp2 = SONG[Addr++];
TR0 = 1;
while(1)
{
fengming= ~fengming;
Delay_xMs(Temp1);
if ( Temp2 == Count )
{
Count = 0;
break;
}
}
}
}
}
/*-------------------------------------------------
功能:主程序
-------------------------------------------------*/
void main()
{
Time0_Init(); //定时器0中断初始化
while(1)
{
Play_Song(0);
}
}本回答被网友采纳
