speak.c

我的一个工程

#include <reg52.h>
sbit relay_dpst=P3^2;
sbit SPEAKER=P3^5;
time1ms()    /* 1 ms delay with XTAL 11.0592MHz */
{
    int i;
    for (i = 0; i<50; i++); // the value shown in this line, 50 was calibrated for 1ms 
    						// you may change it!
}

delay(int n)      /* do nothing n*1ms */
{
    int i;
    for (i=0; i< n ; i++)
    time1ms();
}

delay10us()
{
    int i;
    for (i=0;i<1;i++);

}
void main(void)
{
	while(1)
	{
SPEAKER=~SPEAKER;
relay_dpst=~relay_dpst;
delay(500);
   }
}