Tx not happening!!!

I m using MSC1210. It receives data on UART0.
SCON=0x50--> Serial mode 1(Asynchronous full-duplex).
However, in simulation, only RI(receive interrupt) happens, TI never gets set.
As per the code TI should get set:

SBUF='@';  //These 3 lines are not setting TI bit
SBUF=0x0D;
SBUF=0x0A;

//copying the string into array
for(z=1;z<=4;z++)
{
while(SCON0==0x50){}
init_arr[z]=SBUF;
SCON0=0x50;
}

P0=0x00;
//comparing the string
if (init_arr[1]=='I' && init_arr[2]=='4' && init_arr[3]==' ' && init_arr[4]=='A')
P0=0x0F9;
else
P0=0x0C0;

Please tell me if i m wrong and why it wouldnt work as intended.