For the particular external inputs at port P1,a particular valid data is to be displayed. What the problem is that every hardware resets generates different output datas even when all input conditions are kept constant.For say, data to P1 is kept at FFH and
suppose the valid output data is 2AH. With every new hardware resets,
(even when the input is fixed at FFH and all other conditions kept constant) the output changes randomly

Sorry, I can not understand you. Are you saying that you write 0xff to P1 in order to use it as an input? Use expressions such as "write to port" "read port" to be totally clear.

Pls clarify

Erik