[Resource Download] The download address is as follows:
https://docs.qq.com/doc/DTlRSd01BZXNpRUxl
The design uses a multi-resonator circuit as the driving circuit of the infrared transmitter to drive the infrared transmitter tube to emit infrared rays to the armed area. The receiving end uses a dedicated infrared receiver device to receive the transmitted infrared signal, and the signal is amplified and shaped by the amplifier circuit After the digital gate circuit is driven, the alarm signal is output, and the alarm signal is locked by the alarm signal locking circuit. Even if the police on the scene walk away, the alarm circuit will continue to alarm until the alarm is cancelled manually.
#include <AT89X51.H>
#include <INTRINS.H>
bit flag;
unsigned char count;
void dely500(void) //delay
{
unsigned char i;
for(i=250;i>0;i--)
{
_nop_();
}
}
void main(void)
{
while(1)
{
if(P3_0==0) //Detected low level
{
while(1)//Endless loop alarm
{
