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UniPCemu / Disk images

Currently, various disk images are supported. Disk images are placed in the "disks" folder.

The formats supported are DSK(Floppy disk only), IMG, ISO(CDROM drives only), CUE(CDROM drives only, only "binary" file backend supported), IMA(Floppy disk only) and SFDIMG(Hard disks only).

Created disk images

When a disk image is created it's completely empty. Initialization of the disk (including the boot sector) has to be done by the user (partitioning and formatting).

SFDIMG files

SFDIMG(Superfury Dynamic disk Image) disk images is a sparse harddisk image format used by UniPCEMU. It currently supports drives up to 2TB in size, any multiple of 4096 sectors. At the moment only 512 byte sectors are used. Any other sector size is currently ignored.

The disk image can be converted to/from img disk images using the options in the disks menu.

SFDIMG Defragmentation

As the image gets written to, the disk image will get it's data in non-linear order. Also, once a sector has been filled (that means, it's not filled with zero values anymore) it will be allocated in the disk image. The defragment option takes the sfdimg file and rewrites it with all sectors filled in ascending order. Any useless data (Sectors that have been set to zeroes after initial allocation and lookup tables only pointing to empty sectors or empty lookup tables) is removed during defragmenting. This makes the resulting disk image all cleaned up for transport, compression into an archive and increases read speeds (since unallocated sectors aren't read from the disk image, as they're always filled with zeroes). It also cleans any existant redundant data at the end of the file (failed allocations of sector or lookup table data, due to the host disk being full or unwritable for any reason).

XT-IDE Universal BIOS Configurator

Most of the configuration can be done by loading the ROM to use(XT or AT ROM) and using the auto-detection to detect the drives. Currently, the CD-ROM drives are also detected, so the number of IDE controllers needs to be decreased by one after auto-detecting.

Flashing can be done by selecting the base address(Size of video ROM and any lower-numbered ROM(each ROM rounded up to 2KB units), divide by 16(10 hex) using a hex calculator and finally add C000(hex) for the base segment to use. Don't forget to set the SDP command to Disable for the flashing to work!

An empty 8KB ROM can be created by either using the BIOS ROM from the http://www.xtideuniversalbios.org/binaries/ page(which autodetected base address in the configurator), or by generating a 8KB static disk image, renaming it to the Option ROM filename and moving it to the ROM directory. The official configurator for the XT-IDE BIOS can then be used for configuration and flashing of said flash ROM from a bootable floppy disk image.

Settings not mentioned above(except autodetect) can be left alone(except the required flash parameters for flashing when not autodetected(SDP set to Disabled and number of IDE Controllers)).

Updated