8051: Serial Transmission Interface Code

Description:

The serial port of 8051 is full duplex, i.e., it can transmit and receives simultaneously. The register SBUF is used to hold the data. One is, write-only and is used to hold data to be transmitted out of the8051 via TXD. The other is, read-only and holds the received data from external sources via RXD. Virtual Terminal connected on the TXD to the port RXD and vice versa. The transmitted data display on the virtual terminal. 

 

Code:

#include<reg51.h>

#include<TX.h>

void main()

{

while(1)

{

ini();

transmit('M');

display(" Rajeev");

while(1);

}

}

*/---------------------------------------TX.h----------------------------------------------------*/

void ini();

void transmit(char x);

void delay(int n);

void display(char *s);

void ini() // Initialize Timer 1 for serial communication

{

TMOD=0x20; //Timer1, mode 2, baud rate 9600 bps

TH1=0XFD;

SCON=0x50;

TR1=1;

}

void transmit(char x) // Funtion to transmit serial data

{

SBUF=x;

TR1=1;

while(TI==0);

delay(10);

TI=0;

TR1=0;

}

void delay(int n) //Delay loop

{

int i,j;

for(i=0;i<n;i++)

{

for(j=0;j<10;j++);

}

}

void display(char *s) //to convert string to char

{

while(*s!='\0')

{

transmit(*s);

s++;

}

}

Circuit Diagram: