Strange that you are on com5, and it won't let me use any com less than 6 . . .
Try transmitting data instead. Do an rprintf("hello world"); and see what happens.
Also, your code should be this:
uartSetBaudRate(0, 38400);
while(1)
{
char cByte= uart0GetByte();
if(cByte =='1')
{
backward();
}
}