Ericsson T20

6 - RX
7 - TX
9 - test 
10 - GND
11 - +3V

I think pin 9 and 11 must be join.

const unsigned char para[3]="AT"; 
const unsigned char dial[17] ="ATD0770520112;\n\r"; 

init_uart(UBRR_VAL);
 while (1) 
{
 
for (i=0;i<3;i++)
 {
 send_char(para[i]);
 delay_ms(500);
 }
 send_string("\n\r");
 
for (i=0;i<17;i++)
 {
 send_char(dial[i]);
 delay_ms(200);
 }