at89c51 ports

baftab said:

i am trying to test my controller, so i send random values to my ports

org 000h

mov p2,#0ffh
mov p1,#00h
mov p3,#00fh
mov p0,#0f0h
end

when the ouput is logic 1, the voltage level is 5v and for 0 its 0v
but...its not happening!!
port 2 is giving voltages ranging from 2.4 to 3.2 and same is the case with port0

i hav not connected any load to pins...would tht effect in any case??
its serially communicating ..though :s

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