My Floppy disk controller supports 8 and 5.25 inch 80 track drives. The pin assignment between 50 way and 34 way connectors leading to the drives are as follows: (pins 1,3,5,..... are grounds on both) 8 inch 5.25 (3.5) remark --------------------------- 2 alt I/O (Write current switch) 4 alt I/O 6 alt I/O 8 alt I/O 10 alt I/O 12 alt I/O 14 32 Side Select (which side to use) 16 alt I/O 18 4 alt I/O 20 8 Index (return index pulses from the drive) 22 34 Ready (indicates the drive is ready) 24 26 10 Drive select 0 28 12 Drive select 1 30 14 Drive select 2 32 6 Drive select 3 34 18 Direction select (move head in or out of the centre) 36 20 Step 38 22 Write Data 40 24 Write Gate 42 26 Track 00 (indicates that head is at track 0) 44 28 Write Protect 46 30 Read Data 48 50 Note: The 3.5 inch drive plugs straight into 5.25 socket. With NEC1155 5.25 disk drives set to 360 kb capacity (MS-DOS terms) I can format the 360 kb capacity disk to 800 kb (1 kb sectors, 10 sectors per track, 80 tracks). The same for TEAC FD235hf disk drives (original jumper setting from the factory). The 8 inch drives are Mitsubishi drives, 1.2 Mb. The 40 track drives cannot be used with my Floppy disk controller (maybe they can be used if I knew how to change the BIOS, etc...). I hope this may be of some help. - Henry Brancik E-mail: henryb@aix00.csd.unsw.oz.au ------------------------------