The BAM (block availability map) begins on 38/0 (track 38, sector 0), and continues on 38/3. On the 8250, the BAM extends further to 38/6 and 38/9. The remaining sectors on track 38 are available for general use. BAM Layout 38/0, 3, (6, 9) $00–01 T/S reference to the next BAM sector, or 00/FF if last. 02 DOS version ('C') 04 Lowest BAM track in this block 05 Highest+1 BAM track in this block 06-FF BAM for 50 tracks See also List of floppy disk formats Zone bit recording Group coded recording Notes References External links optusnet.com.au/../SFD1001.htm TOOLS specifically for the SFD1001 & 8250 Drives. Commodore Knowledge Base Technical comparison of Commodore floppy drives (with drive capacities) Commodore Dual Disk Drives Daves Old Computers - Commodore PET (floppy drive images and info) CBM floppy disk drives