STC15F104W uses 315/433 MHz super regenerative module to send/receive data

1. Schematic diagram

315/433 MHz super regenerative module used in the experiment

Transmitter schematic diagram

Schematic diagram of receiving end

2. Transmitter Code

Send data using NEC protocol

#include

#include

#define FOSC 6000000L //IRC frequency

sfr P3M1 = 0xB1;

sfr P3M0 = 0xB2;

sbit SEND = P3 ^ 4; //data sending pin

sbit btn = P3 ^ 2; //Send key

#ifndef fly

#define uchar unsigned char

#endif

#ifndef uint

#define uint unsigned int

#endif

uchar tx_buff[4]; //send buffer

void Delay9ms() //@6.000MHz

{

unsigned char i, j;

i = 53;

j = 132;

do {

while(--j);

} while(--i);

}

void Delay4ms() //@6.000MHz

{

unsigned char i, j;

i = 24;

j = 85;

do {

while(--j);

} while(--i);

}

void Delay560us() //@6.000MHz

{

unsigned char i, j;

i = 4;

j = 65;

do {

while(--j);

} while(--i);

}

void Delay20us() //@6.000MHz

{

unsigned char i;

_nop_();

_nop_();

i = 27;

while(--i);

}

//Send logic 1, logic 1 is 2.25ms, pulse time is 560us

void send_logic_1()

{

SEND = 1;

Delay560us();

SEND = 0;

Delay560us();

Delay560us();

Delay560us();

}

//Send logic 0, logic 0 is 1.12ms, pulse time is 560us

void send_logic_0()

{

SEND = 1;

Delay560us();

SEND = 0;

Delay560us();

}

//Send data of specified length

void send(uchar *dat, uint len)

{

fly i, j, temp;

//Boot code

SEND = 1;

Delay9ms(); //9ms high level

SEND = 0;

Delay4ms(); //4ms low level

//Data code

for(j = 0; j < len; j++){

temp = *that;

for(i = 0; i < 8; i++) {

if((temp & 0x01) == 0x01) {

send_logic_1();

} else {

send_logic_0();

}

temp = temp >> 1;

}

that++;

}

//End code

SEND = 1;

Delay4ms(); //4ms high level

SEND = 0;

}

void main()

{

INT0 = 1;

IT0 = 1; //Set the interrupt type of INT0 (1: falling edge only 0: rising edge and falling edge)

EX0 = 1; // Enable INT0 interrupt

EA = 1;

P3M1 &= 0xEF; //P3.4 push-pull output

P3M0 &= 0xFF;

tx_buff[0] = 0x40;

tx_buff[1] = ~tx_buff[0]; //取反

tx_buff[2] = 0x56;

tx_buff[3] = ~tx_buff[2]; //取反

while(1) {

}

}

//Interrupt service routine

void ex_int0() interrupt 0 //INT0 interrupt entry

{

if(btn == 0) {

Delay20us();

if(btn == 0) {

Delay20us();

send(tx_buff, 4);

}

while(!btn); //wait for button to be pressed

}

}

3. Receiver Code

Receive data using NEC protocol

#include

#include

#ifndef DARK

#define FOSC 6000000L //IRC frequency

#endif

#ifndef fly

#define uchar unsigned char

#endif

#ifndef uint

#define uint unsigned int

#endif

sfr P3M1 = 0xB1;

sfr P3M0 = 0xB2;

sbit RECEIVE = P3 ^ 2; //Data receiving pin, INT0

bit  exint0;

bit flag = 0; //receive flag

sbit LED = P3 ^ 3; //LED

uchar recv[4]; //Receive buffer

void Delay2ms() //@6.000MHz

{

unsigned char i, j;

i = 12;

j = 169;

do {

while(--j);

} while(--i);

}

void Delay200us() //@6.000MHz

{

unsigned char i, j;

i = 2;

j = 39;

do {

while(--j);

} while(--i);

}

void Init_Int0(void)

{

INT0 = 1;

IT0 = 0; //Set the interrupt type of INT0 (1: falling edge only 0: rising edge and falling edge)

EX0 = 1; // Enable INT0 interrupt

}

void main()

{

Heat_Int0();

EA = 1;

P3M1 &= 0xF7; //P3.3 push-pull output

P3M0 &= 0xFF;

flag = 0;

while(1) {

if(flag) {

flag = 0;

LED = !LED; //Receive data and invert IO output

}

}

}

//Interrupt service routine

void External_INT0() interrupt 0 //INT0 interrupt entry

{

flying i, j, N;

uint k;

exint0 = INT0; //Save the status of INT0 port, INT0=0 (falling edge); INT0=1 (rising edge)

EX0 = 0; //Disable interrupt

flag = 0;

Delay2ms();

if(RECEIVE == 0) {

EX0 = 1;

flag = 0;

return;

}

k = 100;

//Confirm that the RECEIVE signal appears

while(RECEIVE && k) { //Wait for RECEIVE to become a low level and skip the 9ms leading high level signal.

Delay200us();

k--;

}

k = 100;

while(!RECEIVE && k) { //Wait for RECEIVE to become high level and skip the 4ms leading low level signal.

Delay200us();

k--;

}

for(i = 0; i < 4; i++) { //4 groups of data

for(j = 0; j < 8; j++) { //Each set of data has 8 bits

k = 100;

while(RECEIVE && k) { //Wait for RECEIVE to become low level

Delay200us();

k--;

}

k = 100;

N = 0;

while(!RECEIVE && k) { //Calculate the RECEIVE low level duration

Delay200us();

N++;

k--;

if(N >= 30) {

EX0 = 1;

flag = 0;

return; //0.14ms count is too long and automatically exits.

}

} //Low level counting completed

recv[i] = recv[i] >> 1; //Fill the highest bit of data with "0"

if(N >= 8) {

recv[i] = recv[i] | 0x80; //Fill the highest bit of data with "1"

}

N = 0;

}

}

if((recv[0] == ~recv[1]) && (recv[2] == ~recv[3])){ //Data verification successful

flag = 1;

}

else{

flag = 0;

}

EX0 = 1; //Open interrupt

}

4. Receive output waveform