On the CBM 8032, I downloaded the schematics from http://www.zimmers.net/anonftp/pub/cbm/pet/, and that helped a lot. Tony's comment about odd and even made things start to make sense. My only question there was did the count start at zero or one :). It appears that the count does start at zero (even). I have some doubts about the schematics since D3 is the one line (on a clear screen) that seems to be always high, and that doesn't correspond to bit 0 always on. BUT it appears that the 4114 at C4 is bad, and I'll scope it out before removing it and putting in a socket. BTW, what is the difference (if any) between the 8032 with the wide plastic label, and the 8032 with the two plastic logos? The one on the right says "CMB Model 8032" and the one of the left says "Commodore". I have both models, but this one is the one with the two plastic logos. And many thanks for the help on copying a floppy on the Mac 128. That worked like a champ. I did find that putting an icon into the trash didn't eject the disk for some reason. However the flower E worked great. Thanks!