NHD File Format

File format documentation

The NHD file format is a HD image format used in the T98-Next emulator. It consists of a simple 512-byte header, followed by the data in C/H/S format

The below comes from kobushi's post on the NFG.Forums

The header starts at the beginning of the file (Offset 0):

Offs Size
____ _____ 
0x00 15-byte ASCIIz String - "T98HDDIMAGE.R0" with a null (0x00 terminator)
0x0F BYTE - Reserved (0x00)
0x10 256-byte ASCIIz String - Comment field, null terminated
0x110 DWORD - Header Size (512 by default)
0x114 DWORD - Number of Cylinders
0x118 WORD - Number of heads
0x11A WORD - Number of sectors
0x11C WORD - Sectors per track
0x11E WORD - Sector length in bytes
0x120 - 0x1FF BYTE - Null (0x00) padding/reserved

An example converted with FIVEC is shown below:

The data segment then follows the header, in standard ordering. Because only a single value is provided for each aspect of drive geometry, varying size sectors and missing sectors are not supported by this format.

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