This is the minimum configuration of a cable that will do parallel file transfers from a PC compatible to an Atari Portfolio. A 25 pin straight-through cable works, but is too bulky for travel. This minimum configuration cable needs only 6 wires. Both ends are male DB-25 connectors, and the connections are straight across. 2 - 2 Data 0 3 - 3 Data 1 11 - 11 Busy 12 - 12 Paper Error 13 - 13 Select 25 - 25 Ground (This can be any or all pins 18 through 25. I used 18 - 18.) Enjoy!