My wife has a CTK-573 from when she was younger. She does not have any software for it. I bought a MIDI-USB cable to connect it, and nothing happened. I learned you need software to connect it. I tried to check the "software download" from the casio website, but could not find one for a keyboard that far back. Could anyone please help us find where the driver is available so I can hook it up to the computer for her? Thank you very much for any assistance.