i m using 12 MHz crystal oscillator and baud rate as 9600. i tested till the microcontroller tranciever pins. it is repeating the letter in given form.

but the program is not working.

#include<reg51.h>
void main()
{
tmod=0x20;
th1=0xfd;
scon=0x50;
tr1=1;

while(1)
{
sbuf='J';
while(ti==0);
ti=0;
}