Many thanks to Jouko Valta (jopi@stekt.oulu.fi) for creation of this list. Model 2031 2040 2041 4040 4031 3040 ------------------------------------------------------------------------------ Drives 1 2 1 2 Disk Size (inch) 5.25 5.25 5.25 5.25 Storage Capacity 170K 170K 170K *340K ? DOS version(s) 2.6 1.0/1.2 1.2 1.2 Heads per Drive 1 1 1 *1 ? Tracks 35 35 ? *35 ? Location of Directory 18 18 ? 18 Directory Entries 144 152 ? 144 Sectors per Track 17-21 17-21 ? 17-21 Bytes per Block 256 256 ? 256 Free Blocks 664 690 ? *1328 ? Buffer Storage (K) 2 4 ? 4 Interface IEEE488 IEEE488 IEEE488 IEEE488 Encoding Method CGR CGR CGR CGR Disk Format ? ? ? ? File Types Supported ? ? ? ? Model 8050 8060 8061 8250 8280 SFD1001 ------------------------------------------------------------------------------ Drives 2 2 2 2 2 1 Disk Size (inch) 5.25 8 8 5.25 8 5.25 Storage Capacity 1.05MB 750K 1.5M 2.12MB ? 1MB DOS version(s) 2.1/2.7 2.5 2.7 2.7 ? ? Heads per Drive 1 2 ? 2 Tracks 77 77 ? Location of Directory 38/39 38/39 ? Directory Entries 224 224 ? Sectors per Track 23-29 23-29 ? Bytes per Block 256 256 ? Free Blocks 4104 8266 ? Buffer Storage (K) 4 4 ? Interface IEEE488 IEEE488 IEEE488 IEEE488 IEEE488 IEEE488 Encoding Method CGR CGR CGR CGR CGR Disk Format ? ? ? ? ? File Types Supported ? ? ? ? ? Model 1540 1541 1551 1570 1571 1581 1542 SFS481 1572* ------------------------------------------------------------------------------ Drives 1 1 1 1 /2* 1 Disk Size (inch) 5.25 5.25 5.25 5.25 3.5 Storage Capacity 170K 170K 170K 340K 800K DOS version(s) 2.6 2.6T ? 3.0 ? Heads per Drive 1 1 1 2 2/1 Tracks 35 35 35 70 80/80 Location of Directory 18 18 18 18 40-41 Directory Entries 144 144 144 144 296 Sectors per Track 17-21 17-21 17-21 17-21 40/10 Bytes per Block 256 256 256 256 256/512 Free Blocks 664 664 664 1328 5280 Buffer Storage (K) 2 2 ? ? ? Interface Serial TED Serial Serial Serial Encoding Method CGR CGR CGR CGR ? Disk Format 2A 2A ? ? ? File Types Supported DSPU ? ? ? ? Notes: The 1571 has 1541 mode, with the 1541 characteristics. 1570 is single-sided 1571. 1572 is Dual 1571. The 1581 was physically a 2 head 80 track, 10 sector, 512 byte/sector drive. Commodore mapped each logical 40 sector, 256 byte/sector track to the two tracks on front and back of disk. So, the logical drive was single sided, 80 tracks, 40 sectors. File Types: D = Deleted, S = SEQ, P = PRG, U = USR, R = Relative