hi,

i am trying to do a matrix keypad routine that is connected only to a "single port." i had this idea of using only a single port for this since all other ports are already occupied.

going on further, given port 1 of an 8051 uC, i would make P1.0 up to P0.3 input ports (columns) and P1.4 up to P1.7 as output ports (rows).

is this kind of setup alright - what i mean half of the P1 byte is input and the other half of it is output?

thanks!