FIM File Format

File format documentation

This is not a dedicated emulator format, but instead, a disk image created by unknown software. As such, the format description below is entirely reverse engineered.

The file itself only contains a 256 byte header, followed by C/H/S data.  There have been two types of disk geometry observed in the wild:

Disk Format DWORD:
01 - HDM - 2 heads, 77 cylinders, 8 sectors/track, 1024 bytes/sector = 1,261,568 bytes of C/H/S data
02 - 2 heads, 77 cylinders, 26 sectors/track, 256 bytes/sector = 1,025,024 bytes of C/H/S data

FIM Header
Offset 0x00 - 0x03 byte "Magic Word" - FIVEC only uses the first four bytes to identify file: 0x01, 0x00, 0x00, 0x00
Offset 0x04 - 0x07 byte -  Disk Format DWORD, used to identify disk geometry above
Offset 0x08 - 0x0B byte -  Track count, DWORD
Offset 0x100+ - Raw data in C/H/S format

HexEditor View

Back to the main page