Store something in $DD00, then load something into the A register STA $DD00 LDA #$xx Writing to a memory location is not copyrightable. Loading something into the A register happens very frequently. Thus the only non-random thing about this pair of instructions is that the C64 has an important IO register at $DD00, which makes it much more likely that such a sequence will occur as a random part of writing programs. It is in any case not copyrightable.