I'm just wondering if anyone knows... is there a difference in the wiring between the "commodore parallel" cable for the 1541 drive and the 21 second backup cable that goes inside the drive? I have no way to double-check the wiring. I know the "Trackmimic" cable was ever so slightly different from the 21 second backup cable though I found a way around that. Anyone with a copy of "Trackminic" please contact me. but as far as the 21 second cable and the parallel cable, does anyone know? Dan.