# Define uchar unsigned characters
# Define uint unsigned integer
int cnt_h，CNT _ l；
sbit spk=p2^3；
//sbit led=p2^0；
uchar cnt，I，step，s _ bit
Code uintyin [7] = {1912170416143212761136/. // 1: low octave 3: high octave
//"Welcome to Beijing" symbol code
Code uint song[]={ 123, 125, 123, 122, 123, 123.
, 122, 12 1, 1 16, 12 1, 122, 123, 125, 122, 123, 126, 125, 125, 123, 123, 122, 123, 122, 12 1, 125, 126,222, 1 15, 123, 123,222,223,
1 16, 123, 122, 122,22 1,423,425, 13 1, 125,226,226, 125, 123, 123, 125,225, 123, 125, 126, 13 1, 132, 13 1, 125, 123, 122, 125,223,223, 123, 125, 13 1, 125,226,23 1, 132, 13 1, 125, 123, 125, 127,226,223, 122, 123, 125, 133,232, 127,33 1,999};
Invalid delay (uinta); //
void init()； //notation code explanation: each tone and its beat are represented by a three-digit number.
Void main() // The hundredth digit of three digits represents an integer multiple of the rhythm.
{//Ten digits indicate pitch (1 bass, 3 for treble).
init()； //Numbers indicate which basic phoneme it is.
while( 1)
{
step =(song[I]/ 100)* 4； //Changing 2 to other numbers can change the beat.
//th 1 =(65536-65535)/256；
//TL 1 =(65536-65535)% 256；
Switch ((song[i]/ 10)% 10)
{
Case 1:
{
Cnt_h=- (Yin [Song [I]%10-1] * 2)/256;
Cnt_l=- (Yin [Song [i]%10-1] * 2)% 256;
Break;
}
Case 2:
{
CNT _ h =-yin[song[I]% 10- 1]/256；
CNT _ l =-yin[song[I]% 10- 1]% 256；
Break;
}
Case 3:
{
Cnt_h=- (Yin [Song [I]%10-1]/2)/256;
Cnt_l=- (Yin [Song [i]%10-1]/2)% 256;
Break;
}
}
TH0 = CNT _ h；
TL0 = CNT _ l；
tr 1 = 1；
TR0 = 1；
Next:
while(cnt！ = step)
Go to the next;
//led = ~ led；
TR0 = 0；
CNT = 0；
tr 1 = 0；
Delay (200);
i++；
If (Song [i]==999)
{
I = 0；
Delay (900);
}
}
}
Void initialization ()
{
EA = 1；
ET0 = 1；
et 1 = 1；
TMOD = 0x 1 1；
I = 0；
CNT = 0；
TR0 = 0；
tr 1 = 0；
}
Void t0(void) interrupt 1
{
TH0 = CNT _ h；
TL0 = CNT _ l；
spk = ~ spk
}
Void t 1 (invalid) interrupt 3
{
//th 1 =(65536-65535)/256；
//TL 1 =(65536-65535)% 256；
cnt++；
}
Invalid delay
{
uint q，k；
for(q = 0； q & lt84; q++)
for(k = 0； k & lta； k++)；
}
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I wrote it a long time ago. Take a look.