This is the schematic diagram of the Commodore 1541/II floppy drive. I drew it 'coz I couldn't find it in anywhere. It was drawn with CirCad, on a PC/AT, but I made a GIF file to make it reproducable without any vector-like stuff. By the way, some things were not fully recognised. The Sony chip is an ASIC, I suppose to get more information about it from Commodore; or simply, compare the diag with an older 1541 release's one. The other new chip (...I don't remember it now) contains some more features than the older custom-chip; It seems to contain the whole clock-divisor part, which was done with a 74LS193 in older versions. ...This way, I see very hard to modify the unit to read MFM disks, for example :-( I don't think if it's free of some funny bugs, so please, send comments/ feedbacks about this one if You think it so. Enjoy... ...Well, I hope, at least You'll not have to trace the board, when trying to make getting up a dead drive, as I did... 8-| , Harsfalvi Levente Levente@Mi.Stud.PMMFK.JPTE.HU ------------------------------------------------------------------------------ Some patches. I found a bug in the schematic diag, there was a lose connect between the custom chip's MTR pin (13) and the uPa2003's 6. pin. So this is a fixed version. '97.01.08 Levente