i tried connecting the serial out to the serial in and the end result = "ff" (on the AMD machine).

pin 2 to pin 3, right??

i, certainly was not sending "ff"!!

anyways i suppose this ceases to be an 8051 related question! maybe something to do with the AMD chipset. Incidentally a serial mouse works fine on this machine when connected to the same serial port.

thanks a lot for the inputs,

sushil