Instead of reading and writting floppy, a continous and limited area on harddisk is used. The area has the same amount of sectors, as the floppy and is called diskimage. Each drive A: and B: separately can be directed to floppy or one of diskimages. You can change the diskimages as you would change the floppies, but by opening some special files.
Using only 20 bytes of RAM makes features like FAT32 and support for .DSK files impossible, so the disk must have special formatting using IDEDOS structures (defined by Garry Lancaster). The harddisk can also contain FAT partitions, but they are not accessible from YaPaDOS.
The IDEDOS partition contains diskimages, that can have various size (e.g. 180kB, 800kB, 5MB). Up to 999 diskimages can be created and accessed.
Diskimages are selected by their numbers 1..999 (0 means floppy) , by opening a file of special name. Only the number after dot matters. Names of diskimages can be listed from a virtual device called superdisk. Superdisk is read-only. After the superdisk is selected, the diskimage then can be selected without the '''^''' sign in file name.
== Commands ==