USART: to send more Bits

Hello,

I'm searching for a function in the Realview Compiler, where I can send more than one Bit over the USART.

__inline void AT91F_US_PutChar (
  AT91PS_USART pUSART,
  int character )
{
    pUSART->US_THR = (character & 0x1FF);
}

e.g. I have a[11] = "Hello World"; and I want to send it with

for(int i=0; i<2; i++)
        {
           AT91F_US_PutChar (COM0,a[i]);
        }

But with this version, only the last Bit (e.g. o) will be transmitted. What would be the reason for this?

best regards
Bernd