* FS 1 and FS 2 File Names may be up to 64 chars. File description text is 128 bytes and file parameters table lenght is 64 bytes. Every FDT is 512 bytes, the first 256 bytes are used for basic features and other 256 bytes are used for optional information about the file. (FDT0 is the master FDT and point FDT1 address if it is
used. FDT1 points FDT2 address, so on. All FDTs of the file point the Directory Descripton Table which the file is in. FDT0 has a checksum that shows Filename and FDT are correctly linked or valid. When Operation System searches for a file, at the first, it does checksum comparison and then name comparison. Filename Checksum is an 8 bit value.
The value at FDT0 offset 32 is Filename Checksum.)
TR-DOS (TR-SINGLIX) File Systems Main
- FS1: 32 bit LBA, 512 bytes per sector
- FS2: 32 bit LBA, 2048 bytes per sector