Use of 51 MCU timer T1 1-interrupt method

/**************************************************

Method 1: Delay method

Hardware: 11.0592MHz crystal, STC89C52, RXD P1.0 TXD P1.1

Baud rate: 9600

Description: T1 is used for timing, mode 1, timing time 50ms, interrupt mode, timing time is up, TF1=1, use the simulated serial port to send character 0x69

**************************************************/

#include "reg52.h"

#define uchar unsigned char

sbit P1_0 = 0x90;

sbit P1_1 = 0x91;

sbit P1_2 = 0x92;

#define RXD P1_0

#define TXD P1_1

#define WRDYN 44 //Write delay

#define RDDYN 43 //Read delay

void Delay2cp(unsigned char i);

//Write a byte to the serial port

void WByte(uchar input)

{

uchar i=8;

TXD=(bit)0; //Send start bit

Delay2cp(39);

//Send 8 bits of data

while(i--)

{

TXD=(bit)(input&0x01); //Transmit low bit first

Delay2cp(36);

input=input>>1;

}

//Send check digit (none)

TXD=(bit)1; //Send end bit

Delay2cp(46);

}

//Read a byte from the serial port

uchar RByte(void)

{

uchar Output=0;

uchar i=8;

uchar temp=RDDYN;

//Send 8 bits of data

Delay2cp(RDDYN*1.5); //Note here, wait until the start bit

while(i--)

{

Output >>=1;

if(RXD) Output |=0x80; //Receive low bit first

Delay2cp(35); //(96-26)/2, the loop takes up 26 instruction cycles in total

}

while(--temp) //Search for the end position within the specified time.

{

Delay2cp(1);

if(RXD)break; //exit after receiving the end bit

}

return Output;

}

//Delay program*

void Delay2cp(unsigned char i)

{

     while(--i); //Exactly two instruction cycles.

}

void main()

{

TMOD=0x10; //T1 mode 1

TH1=0x9E; //50ms initial value

TL1=0x58; //50ms initial value

TR1=1; //Enable timer T1

ET1=1; //Open timer T1 interrupt

EA=1; //Open the general interrupt

while(1){;}

}

void timer1(void) interrupt 3

{

TH1=0x9E; //Reset the timing initial value

TL1=0x58;

WByte(0x69); //Send character

TF1=0; //Software clears interrupt flag

}