"Just send the byte ( consisting of the required bits )from the PC"

Be careful that you configure all the PC stuff to cope with pure binary - otherwise, for example, if you try to send the bit pattern 00001101 (=0x0D) it'll think it's a Carriage Return, and might try adding a Linefeed!

I think this thread refers to a similar problem: http://www.keil.com/discuss/docs/thread3225.htm