Design process sharing of wireless anti loss alarm based on single chip microcomputer

Catalog

Function is introduced

Schematic diagram

PCB

A physical picture

List of components

Source code

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Function is introduced

This design uses 51 Single chip microcomputer combination NRF24L01 Wireless module Design , The anti loss device is divided into two parts , It is divided into slave and master , That is, transmitting module and receiving module , Put the slave on the object that is afraid of being lost , And the host is carried on the host , It can realize two functions ：

• If the communication distance between two modules is exceeded, an alarm will be given , Inform the host in time , Prevent the slave from losing ;
• Within the communication range of the two modules , The slave doesn't know where it is , The host can initiate a search .

Schematic diagram

Schematic diagram of transmission module

Schematic diagram of receiving module

          The difference between the schematic sending module and the receiving module is that the receiving module is less than one button , Everything else is the same , There are single-chip microcomputer minimum systems , Indicator circuit , Buzzer circuit , Wireless module , Serial port circuit . For more information, you can send a private message to the author or add wechat biyezhan007

PCB

Sending module

  Receiving module

A physical picture

 

 

List of components

• MCU base *2
• Single chip microcomputer *2
• Crystal oscillator *2
• Ceramic capacitor *4
• resistance *4
• Electrolytic capacitor *2
• Four foot keys *3
• Power supply base *2
• LED The lamp *4
• DIP8 base *2
• NRF24L01 modular *2
• Buzzer *2
• triode *2

Source code

// The sender main.c

#include "nRF24L01.h"		   // Include header file 
#include "def.h"			   // Include header file 

void Delay_1(unsigned int s)   // The time delay function 
{
	unsigned int i;
	for(i=0; i<s; i++);
	for(i=0; i<s; i++);
}
void delay(unsigned int z)		// The time delay function 
{
	unsigned int x,y;
	for(x=z;x>0;x--)
		for(y=110;y>0;y--);
}


void main(void)					  // The main function 
{
	unsigned int flag;			  // Defining variables 
	unsigned char t  =0,flag_1;
	unsigned char TxBuf[20]={0};	 //  Data temporary storage array 
	unsigned char RxBuf[20]={0};	
	
a:  init_io() ;				 // initialization 
	flag_1=0;
	flag=0;					 // The variable is cleared 
	
	TxBuf[0]='c';			 // send data c
	
	
	while(1)				 // Into the loop 
	{
		//SetRX_Mode();
		if(KEY1 ==0 ) 		 // Press the button 
		{
			TxBuf[0]=0;
			TxBuf[1]=1;		 // send out 01
		}
		else 				 // The key is not pressed 
		{
			TxBuf[0]=1;
			TxBuf[1]=1;		 // send out 11
		}
		nRF24L01_TxPacket(TxBuf);	//  Send buffer data 
		SetRX_Mode();				// Set to receive mode after sending data 

		if(nRF24L01_RxPacket(RxBuf)) // If there is data in the receive buffer 
		{
			nRF24L01_TxPacket(TxBuf);	//  Send buffer data 				
			flag=0;
			flag_1=0;					// The variable is cleared 
		}
		else							// There is no data in the receive buffer , That is, no data was received 
		{
			flag++;						// Timing variable plus 
			if(flag>=80)				// Add to 80
			flag_1=1;					// The variable is set to 1
			delay(5);					// The timing resolution is 5ms, meter 80 The next is 80*5=400ms
		}
		if(flag_1)						// If the variable is 1, timing 400ms, Turn on the alarm 
		for(t=0;t<20;t++)				//for Cycle control light and buzzer alarm 
		{
			LED2=~LED2;
			LED1=~LED1;					// Take the opposite , Achieve the flashing effect 
			delay(80);					// Time delay 80ms
			if(t==19)					//t Add to 19 when 
			{
				goto a;					// go back to while Ahead a:
				flag_1=0;
				flag=0;
			}
		}
	}
}

// The receiver main.c

#include "reg52.h"
#include "nRF24L01.h"
#include "def.h"

#include "delay.h"			  // Include header file 

uchar count_1,count_2,count_3,count,miao,fen,fen_1,fen_2,fen_3,flag_1,flag_2,flag_3;  // Define global variables 

void Delay_1(unsigned int s)		// The time delay function 
{
	unsigned int i;
	for(i=0; i<s; i++);
	for(i=0; i<s; i++);
}
void delay(unsigned int z)			// The time delay function 
{
	unsigned int x,y;
	for(x=z;x>0;x--)
		for(y=110;y>0;y--);
}

void main(void)						 // The main function 
{
	unsigned int flag,f=1000;		 // Defining variables 
	unsigned char t ,flag_1;
	unsigned char TxBuf[20]={0};	 // Buffer data is cleared  
	unsigned char RxBuf[20]={0};	

    init_io() ;						 // initialization 
	while(1)						 // Into the loop 
	{
		TxBuf[0] = 0;
		TxBuf[1] = 1;				 // send data 01
		
		SetRX_Mode();				 // Set reception mode 

		if(nRF24L01_RxPacket(RxBuf))		// If there is data in the receive buffer 
		{	
			nRF24L01_TxPacket(TxBuf);		// Send buffer data 
			if(	RxBuf[0]==0&&RxBuf[1]==1)	// If the received data is 01
			{ 
				for(t=0;t<10;t++)			// The control light and vibration work flash 
				{
					LED1=~LED1;
					LED2=~LED2;				// Take the opposite 
					delay(50);				// Time delay 
				}
			}
			RxBuf[0]= 0;
			RxBuf[1] = 0x00;	 			// Receive buffer data reset 
			flag=0;
			flag_1=0;						// The variable is cleared 
		}
		else								// There is no data in the receive buffer 
		{
			flag++;							// Timing begins 
			if(flag==200)					// Time to go 1 second （200*5ms）
			{
				flag_1=1;					// The variable is set to 1
			}
			delay(5);						//5ms Time delay 
		}
		if(flag_1)							// If the timeout does not receive data , Just turn on the alarm 
		for(t=0;t<10;t++)					//for Cycle start alarm 
		{
			LED2=~LED2;						// Flashing alarm 
			delay(50);						// Time delay 
			
			if(t==9)						// Blink for one cycle 
			{
				flag_1=0;					// The variable is cleared , After returning, judge again whether there is a signal , If there is no signal , Keep calling the police 
				flag=0;
			}
		}
	}
}

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